diff --git a/src/future/FutureIterator.php b/src/future/FutureIterator.php
index 96a41e3d..bb464cd4 100644
--- a/src/future/FutureIterator.php
+++ b/src/future/FutureIterator.php
@@ -1,470 +1,470 @@
 <?php
 
 /**
  * FutureIterator aggregates @{class:Future}s and allows you to respond to them
  * in the order they resolve. This is useful because it minimizes the amount of
  * time your program spends waiting on parallel processes.
  *
  *   $futures = array(
  *     'a.txt' => new ExecFuture('wc -c a.txt'),
  *     'b.txt' => new ExecFuture('wc -c b.txt'),
  *     'c.txt' => new ExecFuture('wc -c c.txt'),
  *   );
  *
  *   foreach (new FutureIterator($futures) as $key => $future) {
  *     // IMPORTANT: keys are preserved but the order of elements is not. This
  *     // construct iterates over the futures in the order they resolve, so the
  *     // fastest future is the one you'll get first. This allows you to start
  *     // doing followup processing as soon as possible.
  *
  *     list($err, $stdout) = $future->resolve();
  *     do_some_processing($stdout);
  *   }
  *
  * For a general overview of futures, see @{article:Using Futures}.
  *
  * @task  basics    Basics
  * @task  config    Configuring Iteration
  * @task  iterator  Iterator Interface
  * @task  internal  Internals
  */
 final class FutureIterator
   extends Phobject
   implements Iterator {
 
   private $hold = array();
   private $wait = array();
   private $work = array();
 
   private $futures = array();
   private $key;
 
   private $limit;
 
   private $timeout;
   private $isTimeout = false;
   private $hasRewound = false;
 
 
 /* -(  Basics  )------------------------------------------------------------- */
 
 
   /**
    * Create a new iterator over a list of futures.
    *
    * @param list  List of @{class:Future}s to resolve.
    * @task basics
    */
   public function __construct(array $futures) {
     assert_instances_of($futures, 'Future');
 
     foreach ($futures as $map_key => $future) {
       $future->setFutureKey($map_key);
       $this->addFuture($future);
     }
   }
 
 
   /**
    * Block until all futures resolve.
    *
    * @return void
    * @task basics
    */
   public function resolveAll() {
     // If a caller breaks out of a "foreach" and then calls "resolveAll()",
     // interpret it to mean that we should iterate over whatever futures
     // remain.
 
     if ($this->hasRewound) {
       while ($this->valid()) {
         $this->next();
       }
     } else {
       iterator_to_array($this);
     }
   }
 
   /**
    * Add another future to the set of futures. This is useful if you have a
    * set of futures to run mostly in parallel, but some futures depend on
    * others.
    *
    * @param Future  @{class:Future} to add to iterator
    * @task basics
    */
   public function addFuture(Future $future) {
     $key = $future->getFutureKey();
 
     if (isset($this->futures[$key])) {
       throw new Exception(
         pht(
           'This future graph already has a future with key "%s". Each '.
           'future must have a unique key.',
           $key));
     }
 
     $this->futures[$key] = $future;
     $this->hold[$key] = $key;
 
     return $this;
   }
 
 
 /* -(  Configuring Iteration  )---------------------------------------------- */
 
 
   /**
    * Set a maximum amount of time you want to wait before the iterator will
    * yield a result. If no future has resolved yet, the iterator will yield
    * null for key and value. Among other potential uses, you can use this to
    * show some busy indicator:
    *
    *   $futures = id(new FutureIterator($futures))
    *     ->setUpdateInterval(1);
    *   foreach ($futures as $future) {
    *     if ($future === null) {
    *       echo "Still working...\n";
    *     } else {
    *       // ...
    *     }
    *   }
    *
    * This will echo "Still working..." once per second as long as futures are
    * resolving. By default, FutureIterator never yields null.
    *
    * @param float Maximum number of seconds to block waiting on futures before
    *              yielding null.
    * @return this
    *
    * @task config
    */
   public function setUpdateInterval($interval) {
     $this->timeout = $interval;
     return $this;
   }
 
 
   /**
    * Limit the number of simultaneously executing futures.
    *
    *  $futures = id(new FutureIterator($futures))
    *    ->limit(4);
    *  foreach ($futures as $future) {
    *    // Run no more than 4 futures simultaneously.
    *  }
    *
    * @param int Maximum number of simultaneous jobs allowed.
    * @return this
    *
    * @task config
    */
   public function limit($max) {
     $this->limit = $max;
     return $this;
   }
 
 
   public function setMaximumWorkingSetSize($limit) {
     $this->limit = $limit;
     return $this;
   }
 
   public function getMaximumWorkingSetSize() {
     return $this->limit;
   }
 
 /* -(  Iterator Interface  )------------------------------------------------- */
 
 
   /**
    * @task iterator
    */
   public function rewind() {
     if ($this->hasRewound) {
       throw new Exception(
         pht('Future graphs can not be rewound.'));
     }
     $this->hasRewound = true;
 
     $this->next();
   }
 
   /**
    * @task iterator
    */
   public function next() {
-    // See T13572. If we preivously resolved and returned a Future, release
+    // See T13572. If we previously resolved and returned a Future, release
     // it now. This prevents us from holding Futures indefinitely when callers
     // like FuturePool build long-lived iterators and keep adding new Futures
     // to them.
     if ($this->key !== null) {
       unset($this->futures[$this->key]);
       $this->key = null;
     }
 
     $this->updateWorkingSet();
 
     if (!$this->work) {
       return;
     }
 
     $start = microtime(true);
     $timeout = $this->timeout;
     $this->isTimeout = false;
 
     $working_set = array_select_keys($this->futures, $this->work);
 
     while (true) {
       // Update every future first. This is a no-op on futures which have
       // already resolved or failed, but we want to give futures an
       // opportunity to make progress even if we can resolve something.
 
       foreach ($working_set as $future_key => $future) {
         $future->updateFuture();
       }
 
       // Check if any future has resolved or failed. If we have any such
       // futures, we'll return the first one from the iterator.
 
       $resolve_key = null;
       foreach ($working_set as $future_key => $future) {
         if ($future->canResolve()) {
           $resolve_key = $future_key;
           break;
         }
       }
 
       // We've found a future to resolve, so we're done here for now.
 
       if ($resolve_key !== null) {
         $this->moveFutureToDone($resolve_key);
         return;
       }
 
       // We don't have any futures to resolve yet. Check if we're reached
       // an update interval.
 
       $wait_time = 1;
       if ($timeout !== null) {
         $elapsed = microtime(true) - $start;
 
         if ($elapsed > $timeout) {
           $this->isTimeout = true;
           return;
         }
 
         $wait_time = min($wait_time, $timeout - $elapsed);
       }
 
       // We're going to wait. If possible, we'd like to wait with sockets.
       // If we can't, we'll just sleep.
 
       $read_sockets = array();
       $write_sockets = array();
       foreach ($working_set as $future_key => $future) {
         $sockets = $future->getReadSockets();
         foreach ($sockets as $socket) {
           $read_sockets[] = $socket;
         }
 
         $sockets = $future->getWriteSockets();
         foreach ($sockets as $socket) {
           $write_sockets[] = $socket;
         }
       }
 
       $use_sockets = ($read_sockets || $write_sockets);
       if ($use_sockets) {
         foreach ($working_set as $future) {
           $wait_time = min($wait_time, $future->getDefaultWait());
         }
         $this->waitForSockets($read_sockets, $write_sockets, $wait_time);
       } else {
         usleep(1000);
       }
     }
   }
 
   /**
    * @task iterator
    */
   public function current() {
     if ($this->isTimeout) {
       return null;
     }
     return $this->futures[$this->key];
   }
 
   /**
    * @task iterator
    */
   public function key() {
     if ($this->isTimeout) {
       return null;
     }
     return $this->key;
   }
 
   /**
    * @task iterator
    */
   public function valid() {
     if ($this->isTimeout) {
       return true;
     }
     return ($this->key !== null);
   }
 
 
 /* -(  Internals  )---------------------------------------------------------- */
 
   /**
    * @task internal
    */
   protected function updateWorkingSet() {
     $limit = $this->getMaximumWorkingSetSize();
     $work_count = count($this->work);
 
     // If we're already working on the maximum number of futures, we just have
     // to wait for something to resolve. There's no benefit to updating the
     // queue since we can never make any meaningful progress.
 
     if ($limit) {
       if ($work_count >= $limit) {
         return;
       }
     }
 
     // If any futures that are currently held are no longer blocked by
     // dependencies, move them from "hold" to "wait".
 
     foreach ($this->hold as $future_key) {
       if (!$this->canMoveFutureToWait($future_key)) {
         continue;
       }
 
       $this->moveFutureToWait($future_key);
     }
 
     $wait_count = count($this->wait);
     $hold_count = count($this->hold);
 
     if (!$work_count && !$wait_count && $hold_count) {
       throw new Exception(
         pht(
           'Future graph is stalled: some futures are held, but no futures '.
           'are waiting or working. The graph can never resolve.'));
     }
 
     // Figure out how many futures we can start. If we don't have a limit,
     // we can start every waiting future. If we do have a limit, we can only
     // start as many futures as we have slots for.
 
     if ($limit) {
       $work_limit = min($limit, $wait_count);
     } else {
       $work_limit = $wait_count;
     }
 
     // If we're ready to start futures, start them now.
 
     if ($work_limit) {
       foreach ($this->wait as $future_key) {
         $this->moveFutureToWork($future_key);
 
         $work_limit--;
         if (!$work_limit) {
           return;
         }
       }
     }
 
   }
 
   private function canMoveFutureToWait($future_key) {
     return true;
   }
 
   private function moveFutureToWait($future_key) {
     unset($this->hold[$future_key]);
     $this->wait[$future_key] = $future_key;
   }
 
   private function moveFutureToWork($future_key) {
     unset($this->wait[$future_key]);
     $this->work[$future_key] = $future_key;
 
     $future = $this->futures[$future_key];
 
     if (!$future->getHasFutureStarted()) {
       $future
         ->setRaiseExceptionOnStart(false)
         ->start();
     }
   }
 
   private function moveFutureToDone($future_key) {
     $this->key = $future_key;
     unset($this->work[$future_key]);
 
     // Before we return, do another working set update so we start any
     // futures that are ready to go as soon as we can.
 
     $this->updateWorkingSet();
   }
 
   /**
    * Wait for activity on one of several sockets.
    *
    * @param  list  List of sockets expected to become readable.
    * @param  list  List of sockets expected to become writable.
    * @param  float Timeout, in seconds.
    * @return void
    */
   private function waitForSockets(
     array $read_list,
     array $write_list,
     $timeout = 1.0) {
 
     static $handler_installed = false;
 
     if (!$handler_installed) {
       // If we're spawning child processes, we need to install a signal handler
       // here to catch cases like execing '(sleep 60 &) &' where the child
       // exits but a socket is kept open. But we don't actually need to do
       // anything because the SIGCHLD will interrupt the stream_select(), as
       // long as we have a handler registered.
       if (function_exists('pcntl_signal')) {
         if (!pcntl_signal(SIGCHLD, array(__CLASS__, 'handleSIGCHLD'))) {
           throw new Exception(pht('Failed to install signal handler!'));
         }
       }
       $handler_installed = true;
     }
 
     $timeout_sec = (int)$timeout;
     $timeout_usec = (int)(1000000 * ($timeout - $timeout_sec));
 
     $exceptfds = array();
     $ok = @stream_select(
       $read_list,
       $write_list,
       $exceptfds,
       $timeout_sec,
       $timeout_usec);
 
     if ($ok === false) {
       // Hopefully, means we received a SIGCHLD. In the worst case, we degrade
       // to a busy wait.
     }
   }
 
   public static function handleSIGCHLD($signo) {
     // This function is a dummy, we just need to have some handler registered
     // so that PHP will get interrupted during "stream_select()". If we don't
     // register a handler, "stream_select()" won't fail.
   }
 
 
 }
diff --git a/src/lint/linter/__tests__/rubocop/convention.lint-test b/src/lint/linter/__tests__/rubocop/convention.lint-test
index b924ae29..776af758 100644
--- a/src/lint/linter/__tests__/rubocop/convention.lint-test
+++ b/src/lint/linter/__tests__/rubocop/convention.lint-test
@@ -1,4 +1,6 @@
 def hello()
 end
 ~~~~~~~~~~
-warning:1:10:-
+warning:1:1
+warning:1:1
+warning:1:10
diff --git a/src/lint/linter/__tests__/rubocop/no_errors.lint-test b/src/lint/linter/__tests__/rubocop/no_errors.lint-test
index 46226a85..b157cfa6 100644
--- a/src/lint/linter/__tests__/rubocop/no_errors.lint-test
+++ b/src/lint/linter/__tests__/rubocop/no_errors.lint-test
@@ -1,4 +1,6 @@
+# frozen_string_literal: true
+
 def hello
   puts 'hello world'
 end
 ~~~~~~~~~~
diff --git a/src/lint/linter/__tests__/rubocop/warning.lint-test b/src/lint/linter/__tests__/rubocop/warning.lint-test
index 8cec4c72..f9d16f70 100644
--- a/src/lint/linter/__tests__/rubocop/warning.lint-test
+++ b/src/lint/linter/__tests__/rubocop/warning.lint-test
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 def hello(unused)
   puts 'hi'
 end
 ~~~~~~~~~
-warning:1:11
+warning:3:11
diff --git a/src/utils/utf8.php b/src/utils/utf8.php
index f03663f3..c92ee533 100644
--- a/src/utils/utf8.php
+++ b/src/utils/utf8.php
@@ -1,982 +1,984 @@
 <?php
 
 /**
  * Convert a string into valid UTF-8. This function is quite slow.
  *
  * When invalid byte subsequences are encountered, they will be replaced with
  * U+FFFD, the Unicode replacement character.
  *
  * This function treats overlong encodings as invalid.
  *
  * @param   string  String to convert to valid UTF-8.
  * @return  string  String with invalid UTF-8 byte subsequences replaced with
  *                  U+FFFD.
  */
 function phutil_utf8ize($string) {
   if (phutil_is_utf8($string)) {
     return $string;
   }
 
   // There is no function to do this in iconv, mbstring or ICU to do this, so
   // do it (very very slowly) in pure PHP.
 
   // TODO: Provide an optional fast C implementation ala fb_utf8ize() if this
   // ever shows up in profiles?
 
   $result = array();
 
   $regex =
     "/([\x01-\x7F]".
       "|[\xC2-\xDF][\x80-\xBF]".
       "|[\xE0][\xA0-\xBF][\x80-\xBF]".
       "|[\xE1-\xEF][\x80-\xBF][\x80-\xBF]".
       "|[\xF0][\x90-\xBF][\x80-\xBF][\x80-\xBF]".
       "|[\xF1-\xF3][\x80-\xBF][\x80-\xBF][\x80-\xBF]".
       "|[\xF4][\x80-\x8F][\x80-\xBF][\x80-\xBF])".
     "|(.)/";
 
   $replacement = "\xEF\xBF\xBD";
 
   $offset = 0;
   $matches = null;
   while (preg_match($regex, $string, $matches, 0, $offset)) {
     if (!isset($matches[2])) {
       $match = $matches[1];
 
       if ($match[0] == "\xED") {
         // If this is a 3-byte character that may be part of one of the
         // surrogate ranges, check if it's actually in those ranges. Reject
         // it as invalid if it is. These sequences are used in UTF16 and
         // functions like json_encode() refuse to encode them.
 
         $codepoint = ((ord($match[0]) & 0x0F) << 12)
                    + ((ord($match[1]) & 0x3F) << 6)
                    + ((ord($match[2]) & 0x3F));
         if ($codepoint >= 0xD800 && $codepoint <= 0xDFFF) {
           $result[] = str_repeat($replacement, strlen($match));
           $offset += strlen($matches[0]);
           continue;
         }
       }
 
       $result[] = $match;
     } else {
       // Unicode replacement character, U+FFFD.
       $result[] = $replacement;
     }
 
     $offset += strlen($matches[0]);
   }
 
   return implode('', $result);
 }
 
 
 /**
  * Determine if a string is valid UTF-8, with only basic multilingual plane
  * characters. This is particularly important because MySQL's `utf8` column
  * types silently truncate strings which contain characters outside of this
  * set.
  *
  * @param string  String to test for being valid UTF-8 with only characters in
  *                the basic multilingual plane.
  * @return bool   True if the string is valid UTF-8 with only BMP characters.
  */
 function phutil_is_utf8_with_only_bmp_characters($string) {
   return phutil_is_utf8_slowly($string, $only_bmp = true);
 }
 
 
 /**
  * Determine if a string is valid UTF-8.
  *
  * @param string  Some string which may or may not be valid UTF-8.
  * @return bool    True if the string is valid UTF-8.
  */
 function phutil_is_utf8($string) {
   if (function_exists('mb_check_encoding')) {
     // See T13527. In some versions of PHP, "mb_check_encoding()" strictly
     // requires a string parameter.
     $string = phutil_string_cast($string);
 
     // If mbstring is available, this is significantly faster than using PHP.
     return mb_check_encoding($string, 'UTF-8');
   }
 
   return phutil_is_utf8_slowly($string);
 }
 
 
 /**
  * Determine if a string is valid UTF-8, slowly.
  *
  * This works on any system, but has very poor performance.
  *
  * You should call @{function:phutil_is_utf8} instead of this function, as
  * that function can use more performant mechanisms if they are available on
  * the system.
  *
  * @param string  Some string which may or may not be valid UTF-8.
  * @param bool    True to require all characters be part of the basic
  *                multilingual plane (no more than 3-bytes long).
  * @return bool   True if the string is valid UTF-8.
  */
 function phutil_is_utf8_slowly($string, $only_bmp = false) {
   // First, check the common case of normal ASCII strings. We're fine if
   // the string contains no bytes larger than 127.
   if (preg_match('/^[\x01-\x7F]+\z/', $string)) {
     return true;
   }
 
   // NOTE: In the past, we used a large regular expression in the form of
   // '(x|y|z)+' to match UTF8 strings. However, PCRE can segfaults on patterns
   // like this at relatively small input sizes, at least on some systems
   // (observed on OSX and Windows). This is apparently because the internal
   // implementation is recursive and it blows the stack.
 
   // See <https://bugs.php.net/bug.php?id=45735> for some discussion. Since the
   // input limit is extremely low (less than 50KB on my system), do this check
   // very very slowly in PHP instead. See also T5316.
 
   $len = strlen($string);
   for ($ii = 0; $ii < $len; $ii++) {
     $chr = ord($string[$ii]);
     if ($chr >= 0x01 && $chr <= 0x7F) {
       continue;
     } else if ($chr >= 0xC2 && $chr <= 0xDF) {
       ++$ii;
       if ($ii >= $len) {
         return false;
       }
       $chr = ord($string[$ii]);
       if ($chr >= 0x80 && $chr <= 0xBF) {
         continue;
       }
       return false;
     } else if ($chr == 0xED) {
       // See T11525. Some sequences in this block are surrogate codepoints
       // that are reserved for use in UTF16. We should reject them.
       $codepoint = ($chr & 0x0F) << 12;
       ++$ii;
       if ($ii >= $len) {
         return false;
       }
       $chr = ord($string[$ii]);
       $codepoint += ($chr & 0x3F) << 6;
       if ($chr >= 0x80 && $chr <= 0xBF) {
         ++$ii;
         if ($ii >= $len) {
           return false;
         }
         $chr = ord($string[$ii]);
         $codepoint += ($chr & 0x3F);
 
         if ($codepoint >= 0xD800 && $codepoint <= 0xDFFF) {
           // Reject these surrogate codepoints.
           return false;
         }
 
         if ($chr >= 0x80 && $chr <= 0xBF) {
           continue;
         }
       }
       return false;
     } else if ($chr > 0xE0 && $chr <= 0xEF) {
       ++$ii;
       if ($ii >= $len) {
         return false;
       }
       $chr = ord($string[$ii]);
       if ($chr >= 0x80 && $chr <= 0xBF) {
         ++$ii;
         if ($ii >= $len) {
           return false;
         }
         $chr = ord($string[$ii]);
         if ($chr >= 0x80 && $chr <= 0xBF) {
           continue;
         }
       }
       return false;
     } else if ($chr == 0xE0) {
       ++$ii;
       if ($ii >= $len) {
         return false;
       }
       $chr = ord($string[$ii]);
 
       // NOTE: This range starts at 0xA0, not 0x80. The values 0x80-0xA0 are
       // "valid", but not minimal representations, and MySQL rejects them. We're
       // special casing this part of the range.
 
       if ($chr >= 0xA0 && $chr <= 0xBF) {
         ++$ii;
         if ($ii >= $len) {
           return false;
         }
         $chr = ord($string[$ii]);
         if ($chr >= 0x80 && $chr <= 0xBF) {
           continue;
         }
       }
       return false;
     } else if (!$only_bmp) {
       if ($chr > 0xF0 && $chr <= 0xF4) {
         ++$ii;
         if ($ii >= $len) {
           return false;
         }
         $chr = ord($string[$ii]);
         if ($chr >= 0x80 && $chr <= 0xBF) {
           ++$ii;
           if ($ii >= $len) {
             return false;
           }
           $chr = ord($string[$ii]);
           if ($chr >= 0x80 && $chr <= 0xBF) {
             ++$ii;
             if ($ii >= $len) {
               return false;
             }
             $chr = ord($string[$ii]);
             if ($chr >= 0x80 && $chr <= 0xBF) {
               continue;
             }
           }
         }
       } else if ($chr == 0xF0) {
         ++$ii;
         if ($ii >= $len) {
           return false;
         }
         $chr = ord($string[$ii]);
 
         // NOTE: As above, this range starts at 0x90, not 0x80. The values
         // 0x80-0x90 are not minimal representations.
 
         if ($chr >= 0x90 && $chr <= 0xBF) {
           ++$ii;
           if ($ii >= $len) {
             return false;
           }
           $chr = ord($string[$ii]);
           if ($chr >= 0x80 && $chr <= 0xBF) {
             ++$ii;
             if ($ii >= $len) {
               return false;
             }
             $chr = ord($string[$ii]);
             if ($chr >= 0x80 && $chr <= 0xBF) {
               continue;
             }
           }
         }
       }
     }
 
     return false;
   }
 
   return true;
 }
 
 
 /**
  * Find the character length of a UTF-8 string.
  *
  * @param string A valid utf-8 string.
  * @return int   The character length of the string.
  */
 function phutil_utf8_strlen($string) {
   if (function_exists('utf8_decode')) {
     return strlen(utf8_decode($string));
   }
   return count(phutil_utf8v($string));
 }
 
 
 /**
  * Find the console display length of a UTF-8 string. This may differ from the
  * character length of the string if it contains double-width characters, like
  * many Chinese characters.
  *
  * This method is based on a C implementation here, which is based on the IEEE
  * standards. The source has more discussion and addresses more considerations
  * than this implementation does.
  *
  *   http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
  *
  * NOTE: We currently assume width 1 for East-Asian ambiguous characters.
  *
  * NOTE: This function is VERY slow.
  *
  * @param   string  A valid UTF-8 string.
  * @return  int     The console display length of the string.
  */
 function phutil_utf8_console_strlen($string) {
   // Formatting and colors don't contribute any width in the console.
   $string = preg_replace("/\x1B\[\d*m/", '', $string);
 
   // In the common case of an ASCII string, just return the string length.
   if (preg_match('/^[\x01-\x7F]*\z/', $string)) {
     return strlen($string);
   }
 
   $len = 0;
 
   // NOTE: To deal with combining characters, we're splitting the string into
   // glyphs first (characters with combiners) and then counting just the width
   // of the first character in each glyph.
 
   $display_glyphs = phutil_utf8v_combined($string);
   foreach ($display_glyphs as $display_glyph) {
     $glyph_codepoints = phutil_utf8v_codepoints($display_glyph);
     foreach ($glyph_codepoints as $c) {
       if ($c == 0) {
         break;
       }
 
       $len += 1 +
         ($c >= 0x1100 &&
           ($c <= 0x115F ||                    /* Hangul Jamo init. consonants */
             $c == 0x2329 || $c == 0x232A ||
             ($c >= 0x2E80 && $c <= 0xA4CF &&
               $c != 0x303F) ||                  /* CJK ... Yi */
             ($c >= 0xAC00 && $c <= 0xD7A3) || /* Hangul Syllables */
             ($c >= 0xF900 && $c <= 0xFAFF) || /* CJK Compatibility Ideographs */
             ($c >= 0xFE10 && $c <= 0xFE19) || /* Vertical forms */
             ($c >= 0xFE30 && $c <= 0xFE6F) || /* CJK Compatibility Forms */
             ($c >= 0xFF00 && $c <= 0xFF60) || /* Fullwidth Forms */
             ($c >= 0xFFE0 && $c <= 0xFFE6) ||
             ($c >= 0x20000 && $c <= 0x2FFFD) ||
             ($c >= 0x30000 && $c <= 0x3FFFD)));
 
       break;
     }
   }
 
   return $len;
 }
 
 
 /**
  * Test if a string contains Chinese, Japanese, or Korean characters.
  *
  * Most languages use spaces to separate words, but these languages do not.
  *
  * @param string String to examine, in UTF8.
  * @return bool True if the string contains Chinese, Japanese, or Korean
  *   characters.
  */
 function phutil_utf8_is_cjk($string) {
   $codepoints = phutil_utf8v_codepoints($string);
 
   foreach ($codepoints as $codepoint) {
     // CJK Unified Ideographs
     if ($codepoint >= 0x4E00 && $codepoint <= 0x9FFF) {
       return true;
     }
 
     // CJK Unified Ideographs Extension A
     if ($codepoint >= 0x3400 && $codepoint <= 0x4DBF) {
       return true;
     }
 
     // CJK Unified Ideographs Extension B
     if ($codepoint >= 0x20000 && $codepoint <= 0x2A6DF) {
       return true;
     }
 
     // CJK Unified Ideographs Extension C
     if ($codepoint >= 0x2A700 && $codepoint <= 0x2B73F) {
       return true;
     }
 
     // CJK Unified Ideographs Extension D
     if ($codepoint >= 0x2B740 && $codepoint <= 0x2B81F) {
       return true;
     }
 
     // CJK Unified Ideographs Extension E
     if ($codepoint >= 0x2B820 && $codepoint <= 0x2CEAF) {
       return true;
     }
 
     // CJK Unified Ideographs Extension F
     if ($codepoint >= 0x2CEB0 && $codepoint <= 0x2EBEF) {
       return true;
     }
 
     // CJK Compatibility Ideographs
     if ($codepoint >= 0xF900 && $codepoint <= 0xFAFF) {
       return true;
     }
   }
 
   return false;
 }
 
 
 /**
  * Split a UTF-8 string into an array of characters. Combining characters are
  * also split.
  *
  * @param string A valid utf-8 string.
  * @param int|null Stop processing after examining this many bytes.
  * @return list  A list of characters in the string.
  */
 function phutil_utf8v($string, $byte_limit = null) {
+  $string = phutil_string_cast($string);
+
   $res = array();
   $len = strlen($string);
 
   $ii = 0;
   while ($ii < $len) {
     $byte = $string[$ii];
     if ($byte <= "\x7F") {
       $res[] = $byte;
       $ii += 1;
 
       if ($byte_limit && ($ii >= $byte_limit)) {
         break;
       }
 
       continue;
     } else if ($byte < "\xC0") {
       throw new Exception(
         pht('Invalid UTF-8 string passed to %s.', __FUNCTION__));
     } else if ($byte <= "\xDF") {
       $seq_len = 2;
     } else if ($byte <= "\xEF") {
       $seq_len = 3;
     } else if ($byte <= "\xF7") {
       $seq_len = 4;
     } else if ($byte <= "\xFB") {
       $seq_len = 5;
     } else if ($byte <= "\xFD") {
       $seq_len = 6;
     } else {
       throw new Exception(
         pht('Invalid UTF-8 string passed to %s.', __FUNCTION__));
     }
 
     if ($ii + $seq_len > $len) {
       throw new Exception(
         pht('Invalid UTF-8 string passed to %s.', __FUNCTION__));
     }
     for ($jj = 1; $jj < $seq_len; ++$jj) {
       if ($string[$ii + $jj] >= "\xC0") {
         throw new Exception(
           pht('Invalid UTF-8 string passed to %s.', __FUNCTION__));
       }
     }
     $res[] = substr($string, $ii, $seq_len);
     $ii += $seq_len;
 
     if ($byte_limit && ($ii >= $byte_limit)) {
       break;
     }
   }
 
   return $res;
 }
 
 
 /**
  * Split a UTF-8 string into an array of codepoints (as integers).
  *
  * @param   string  A valid UTF-8 string.
  * @return  list    A list of codepoints, as integers.
  */
 function phutil_utf8v_codepoints($string) {
   $str_v = phutil_utf8v($string);
 
   foreach ($str_v as $key => $char) {
     $c = ord($char[0]);
     $v = 0;
 
     if (($c & 0x80) == 0) {
       $v = $c;
     } else if (($c & 0xE0) == 0xC0) {
       $v = (($c & 0x1F) << 6)
          + ((ord($char[1]) & 0x3F));
     } else if (($c & 0xF0) == 0xE0) {
       $v = (($c & 0x0F) << 12)
          + ((ord($char[1]) & 0x3F) << 6)
          + ((ord($char[2]) & 0x3F));
     } else if (($c & 0xF8) == 0xF0) {
       $v = (($c & 0x07) << 18)
          + ((ord($char[1]) & 0x3F) << 12)
          + ((ord($char[2]) & 0x3F) << 6)
          + ((ord($char[3]) & 0x3F));
     } else if (($c & 0xFC) == 0xF8) {
       $v = (($c & 0x03) << 24)
          + ((ord($char[1]) & 0x3F) << 18)
          + ((ord($char[2]) & 0x3F) << 12)
          + ((ord($char[3]) & 0x3F) << 6)
          + ((ord($char[4]) & 0x3F));
     } else if (($c & 0xFE) == 0xFC) {
       $v = (($c & 0x01) << 30)
          + ((ord($char[1]) & 0x3F) << 24)
          + ((ord($char[2]) & 0x3F) << 18)
          + ((ord($char[3]) & 0x3F) << 12)
          + ((ord($char[4]) & 0x3F) << 6)
          + ((ord($char[5]) & 0x3F));
     }
 
     $str_v[$key] = $v;
   }
 
   return $str_v;
 }
 
 
 /**
  * Convert a Unicode codepoint into a UTF8-encoded string.
  *
  * @param int Unicode codepoint.
  * @return string UTF8 encoding.
  */
 function phutil_utf8_encode_codepoint($codepoint) {
   if ($codepoint < 0x80) {
     $r = chr($codepoint);
   } else if ($codepoint < 0x800) {
     $r = chr(0xC0 | (($codepoint >> 6)  & 0x1F)).
          chr(0x80 | (($codepoint)       & 0x3F));
   } else if ($codepoint < 0x10000) {
     $r = chr(0xE0 | (($codepoint >> 12) & 0x0F)).
          chr(0x80 | (($codepoint >> 6)  & 0x3F)).
          chr(0x80 | (($codepoint)       & 0x3F));
   } else if ($codepoint < 0x110000) {
     $r = chr(0xF0 | (($codepoint >> 18) & 0x07)).
          chr(0x80 | (($codepoint >> 12) & 0x3F)).
          chr(0x80 | (($codepoint >> 6)  & 0x3F)).
          chr(0x80 | (($codepoint)       & 0x3F));
   } else {
     throw new Exception(
       pht(
         'Encoding UTF8 codepoint "%s" is not supported.',
         $codepoint));
   }
 
   return $r;
 }
 
 
 /**
  * Hard-wrap a block of UTF-8 text with embedded HTML tags and entities.
  *
  * @param   string An HTML string with tags and entities.
  * @return  list   List of hard-wrapped lines.
  */
 function phutil_utf8_hard_wrap_html($string, $width) {
   $break_here = array();
 
   // Convert the UTF-8 string into a list of UTF-8 characters.
   $vector = phutil_utf8v($string);
   $len = count($vector);
   $char_pos = 0;
   for ($ii = 0; $ii < $len; ++$ii) {
     // An ampersand indicates an HTML entity; consume the whole thing (until
     // ";") but treat it all as one character.
     if ($vector[$ii] == '&') {
       do {
         ++$ii;
       } while ($vector[$ii] != ';');
       ++$char_pos;
     // An "<" indicates an HTML tag, consume the whole thing but don't treat
     // it as a character.
     } else if ($vector[$ii] == '<') {
       do {
         ++$ii;
       } while ($vector[$ii] != '>');
     } else {
       ++$char_pos;
     }
 
     // Keep track of where we need to break the string later.
     if ($char_pos == $width) {
       $break_here[$ii] = true;
       $char_pos = 0;
     }
   }
 
   $result = array();
   $string = '';
   foreach ($vector as $ii => $char) {
     $string .= $char;
     if (isset($break_here[$ii])) {
       $result[] = $string;
       $string = '';
     }
   }
 
   if (strlen($string)) {
     $result[] = $string;
   }
 
   return $result;
 }
 
 /**
   * Hard-wrap a block of UTF-8 text with no embedded HTML tags and entities.
   *
   * @param string A non HTML string
   * @param int Width of the hard-wrapped lines
   * @return list List of hard-wrapped lines.
   */
 function phutil_utf8_hard_wrap($string, $width) {
   $result = array();
 
   $lines = phutil_split_lines($string, $retain_endings = false);
   foreach ($lines as $line) {
 
     // Convert the UTF-8 string into a list of UTF-8 characters.
     $vector = phutil_utf8v($line);
 
     $len = count($vector);
     $buffer = '';
 
     for ($ii = 1; $ii <= $len; ++$ii) {
       $buffer .= $vector[$ii - 1];
       if (($ii % $width) === 0) {
         $result[] = $buffer;
         $buffer = '';
       }
     }
 
     if (strlen($buffer)) {
       $result[] = $buffer;
     }
   }
 
   return $result;
 }
 
 /**
  * Convert a string from one encoding (like ISO-8859-1) to another encoding
  * (like UTF-8).
  *
  * This is primarily a thin wrapper around `mb_convert_encoding()` which checks
  * you have the extension installed, since we try to require the extension
  * only if you actually need it (i.e., you want to work with encodings other
  * than UTF-8).
  *
  * NOTE: This function assumes that the input is in the given source encoding.
  * If it is not, it may not output in the specified target encoding. If you
  * need to perform a hard conversion to UTF-8, use this function in conjunction
  * with @{function:phutil_utf8ize}. We can detect failures caused by invalid
  * encoding names, but `mb_convert_encoding()` fails silently if the
  * encoding name identifies a real encoding but the string is not actually
  * encoded with that encoding.
  *
  * @param string String to re-encode.
  * @param string Target encoding name, like "UTF-8".
  * @param string Source encoding name, like "ISO-8859-1".
  * @return string Input string, with converted character encoding.
  *
  * @phutil-external-symbol function mb_convert_encoding
  */
 function phutil_utf8_convert($string, $to_encoding, $from_encoding) {
   if (!$from_encoding) {
     throw new InvalidArgumentException(
       pht(
         'Attempting to convert a string encoding, but no source encoding '.
         'was provided. Explicitly provide the source encoding.'));
   }
   if (!$to_encoding) {
     throw new InvalidArgumentException(
       pht(
         'Attempting to convert a string encoding, but no target encoding '.
         'was provided. Explicitly provide the target encoding.'));
   }
 
   // Normalize encoding names so we can no-op the very common case of UTF8
   // to UTF8 (or any other conversion where both encodings are identical).
   $to_upper = strtoupper(str_replace('-', '', $to_encoding));
   $from_upper = strtoupper(str_replace('-', '', $from_encoding));
   if ($from_upper == $to_upper) {
     return $string;
   }
 
   if (!function_exists('mb_convert_encoding')) {
     throw new Exception(
       pht(
         "Attempting to convert a string encoding from '%s' to '%s', ".
         "but the '%s' PHP extension is not available. Install %s to ".
         "work with encodings other than UTF-8.",
         $from_encoding,
         $to_encoding,
         'mbstring',
         'mbstring'));
   }
 
   $result = @mb_convert_encoding($string, $to_encoding, $from_encoding);
 
   if ($result === false) {
     $message = error_get_last();
     if ($message) {
       $message = idx($message, 'message', pht('Unknown error.'));
     }
     throw new Exception(
       pht(
         "String conversion from encoding '%s' to encoding '%s' failed: %s",
         $from_encoding,
         $to_encoding,
         $message));
   }
 
   return $result;
 }
 
 
 /**
  * Convert a string to title case in a UTF8-aware way. This function doesn't
  * necessarily do a great job, but the builtin implementation of `ucwords()` can
  * completely destroy inputs, so it just has to be better than that. Similar to
  * @{function:ucwords}.
  *
  * @param   string  UTF-8 input string.
  * @return  string  Input, in some semblance of title case.
  */
 function phutil_utf8_ucwords($str) {
   // NOTE: mb_convert_case() discards uppercase letters in words when converting
   // to title case. For example, it will convert "AAA" into "Aaa", which is
   // undesirable.
 
   $v = phutil_utf8v($str);
   $result = '';
   $last = null;
 
   $ord_a = ord('a');
   $ord_z = ord('z');
   foreach ($v as $c) {
     $convert = false;
     if ($last === null || $last === ' ') {
       $o = ord($c[0]);
       if ($o >= $ord_a && $o <= $ord_z) {
         $convert = true;
       }
     }
 
     if ($convert) {
       $result .= phutil_utf8_strtoupper($c);
     } else {
       $result .= $c;
     }
 
     $last = $c;
   }
 
   return $result;
 }
 
 
 /**
  * Convert a string to lower case in a UTF8-aware way. Similar to
  * @{function:strtolower}.
  *
  * @param   string  UTF-8 input string.
  * @return  string  Input, in some semblance of lower case.
  *
  * @phutil-external-symbol function mb_convert_case
  */
 function phutil_utf8_strtolower($str) {
   if (function_exists('mb_convert_case')) {
     return mb_convert_case($str, MB_CASE_LOWER, 'UTF-8');
   }
 
   static $map;
   if ($map === null) {
     $map = array_combine(
       range('A', 'Z'),
       range('a', 'z'));
   }
 
   return phutil_utf8_strtr($str, $map);
 }
 
 
 /**
  * Convert a string to upper case in a UTF8-aware way. Similar to
  * @{function:strtoupper}.
  *
  * @param   string  UTF-8 input string.
  * @return  string  Input, in some semblance of upper case.
  *
  * @phutil-external-symbol function mb_convert_case
  */
 function phutil_utf8_strtoupper($str) {
   if (function_exists('mb_convert_case')) {
     return mb_convert_case($str, MB_CASE_UPPER, 'UTF-8');
   }
 
   static $map;
   if ($map === null) {
     $map = array_combine(
       range('a', 'z'),
       range('A', 'Z'));
   }
 
   return phutil_utf8_strtr($str, $map);
 }
 
 
 /**
  * Replace characters in a string in a UTF-aware way. Similar to
  * @{function:strtr}.
  *
  * @param   string              UTF-8 input string.
  * @param   map<string, string> Map of characters to replace.
  * @return  string              Input with translated characters.
  */
 function phutil_utf8_strtr($str, array $map) {
   $v = phutil_utf8v($str);
   $result = '';
   foreach ($v as $c) {
     if (isset($map[$c])) {
       $result .= $map[$c];
     } else {
       $result .= $c;
     }
   }
 
   return $result;
 }
 
 /**
  * Determine if a given unicode character is a combining character or not.
  *
  * @param   string              A single unicode character.
  * @return  boolean             True or false.
  */
 function phutil_utf8_is_combining_character($character) {
   $components = phutil_utf8v_codepoints($character);
 
   // Combining Diacritical Marks (0300 - 036F).
   // Combining Diacritical Marks Supplement (1DC0 - 1DFF).
   // Combining Diacritical Marks for Symbols (20D0 - 20FF).
   // Combining Half Marks (FE20 - FE2F).
 
   foreach ($components as $codepoint) {
     if ($codepoint >= 0x0300 && $codepoint <= 0x036F ||
          $codepoint >= 0x1DC0 && $codepoint <= 0x1DFF ||
          $codepoint >= 0x20D0 && $codepoint <= 0x20FF ||
          $codepoint >= 0xFE20 && $codepoint <= 0xFE2F) {
       return true;
     }
   }
 
   return false;
 }
 
 
 /**
  * Split a UTF-8 string into an array of characters. Combining characters
  * are not split.
  *
  * @param string A valid utf-8 string.
  * @return list  A list of characters in the string.
  */
 function phutil_utf8v_combined($string) {
   $components = phutil_utf8v($string);
   return phutil_utf8v_combine_characters($components);
 }
 
 
 /**
  * Merge combining characters in a UTF-8 string.
  *
  * This is a low-level method which can allow other operations to do less work.
  * If you have a string, call @{method:phutil_utf8v_combined} instead.
  *
  * @param list List of UTF-8 characters.
  * @return list List of UTF-8 strings with combining characters merged.
  */
 function phutil_utf8v_combine_characters(array $characters) {
   if (!$characters) {
     return array();
   }
 
   // If the first character in the string is a combining character,
   // start with a space.
   if (phutil_utf8_is_combining_character($characters[0])) {
     $buf = ' ';
   } else {
     $buf = null;
   }
 
   $parts = array();
   foreach ($characters as $character) {
     if (!isset($character[1])) {
       // This an optimization: there are no one-byte combining characters,
       // so we can just pass these through unmodified.
       $is_combining = false;
     } else {
       $is_combining = phutil_utf8_is_combining_character($character);
     }
 
     if ($is_combining) {
       $buf .= $character;
     } else {
       if ($buf !== null) {
         $parts[] = $buf;
       }
       $buf = $character;
     }
   }
 
   $parts[] = $buf;
 
   return $parts;
 }
 
 
 /**
  * Return the current system locale setting (LC_ALL).
  *
  * @return string Current system locale setting.
  */
 function phutil_get_system_locale() {
   $locale = setlocale(LC_ALL, 0);
 
   if ($locale === false) {
     throw new Exception(
       pht(
         'Unable to determine current system locale (call to '.
         '"setlocale(LC_ALL, 0)" failed).'));
   }
 
   return $locale;
 }
 
 
 /**
  * Test if a system locale (LC_ALL) is available on the system.
  *
  * @param string Locale name like "en_US.UTF-8".
  * @return bool True if the locale is available.
  */
 function phutil_is_system_locale_available($locale) {
   $old_locale = phutil_get_system_locale();
   $is_available = @setlocale(LC_ALL, $locale);
   setlocale(LC_ALL, $old_locale);
 
   return ($is_available !== false);
 }
 
 
 /**
  * Set the system locale (LC_ALL) to a particular value.
  *
  * @param string New locale setting.
  * @return void
  */
 function phutil_set_system_locale($locale) {
   $ok = @setlocale(LC_ALL, $locale);
   if (!$ok) {
     throw new Exception(
       pht(
         'Failed to set system locale (to "%s").',
         $locale));
   }
 }
diff --git a/src/workflow/ArcanistDiffWorkflow.php b/src/workflow/ArcanistDiffWorkflow.php
index 7997458d..f0b48acf 100644
--- a/src/workflow/ArcanistDiffWorkflow.php
+++ b/src/workflow/ArcanistDiffWorkflow.php
@@ -1,2879 +1,2890 @@
 <?php
 
 /**
  * Sends changes from your working copy to Differential for code review.
  *
  * @task lintunit   Lint and Unit Tests
  * @task message    Commit and Update Messages
  * @task diffspec   Diff Specification
  * @task diffprop   Diff Properties
  */
 final class ArcanistDiffWorkflow extends ArcanistWorkflow {
 
   private $console;
   private $hasWarnedExternals = false;
   private $unresolvedLint;
   private $testResults;
   private $diffID;
   private $revisionID;
   private $diffPropertyFutures = array();
   private $commitMessageFromRevision;
   private $hitAutotargets;
   private $revisionTransactions;
   private $revisionIsDraft;
 
   const STAGING_PUSHED = 'pushed';
   const STAGING_USER_SKIP = 'user.skip';
   const STAGING_DIFF_RAW = 'diff.raw';
   const STAGING_REPOSITORY_UNKNOWN = 'repository.unknown';
   const STAGING_REPOSITORY_UNAVAILABLE = 'repository.unavailable';
   const STAGING_REPOSITORY_UNSUPPORTED = 'repository.unsupported';
   const STAGING_REPOSITORY_UNCONFIGURED = 'repository.unconfigured';
   const STAGING_CLIENT_UNSUPPORTED = 'client.unsupported';
 
   public function getWorkflowName() {
     return 'diff';
   }
 
   public function getCommandSynopses() {
     return phutil_console_format(<<<EOTEXT
       **diff** [__paths__] (svn)
       **diff** [__commit__] (git, hg)
 EOTEXT
       );
   }
 
   public function getCommandHelp() {
     return phutil_console_format(<<<EOTEXT
           Supports: git, svn, hg
           Generate a Differential diff or revision from local changes.
 
           Under git and mercurial, you can specify a commit (like __HEAD^^^__
           or __master__) and Differential will generate a diff against the
           merge base of that commit and your current working directory parent.
 
           Under svn, you can choose to include only some of the modified files
           in the working copy in the diff by specifying their paths. If you
           omit paths, all changes are included in the diff.
 EOTEXT
       );
   }
 
   public function requiresWorkingCopy() {
     return !$this->isRawDiffSource();
   }
 
   public function requiresConduit() {
     return true;
   }
 
   public function requiresAuthentication() {
     return true;
   }
 
   public function requiresRepositoryAPI() {
     if (!$this->isRawDiffSource()) {
       return true;
     }
 
     return false;
   }
 
   public function getDiffID() {
     return $this->diffID;
   }
 
   public function getArguments() {
     $arguments = array(
       'message' => array(
         'short'       => 'm',
         'param'       => 'message',
         'help' => pht(
           'When updating a revision, use the specified message instead of '.
           'prompting.'),
       ),
       'message-file' => array(
         'short' => 'F',
         'param' => 'file',
         'paramtype' => 'file',
         'help' => pht(
           'When creating a revision, read revision information '.
           'from this file.'),
       ),
       'edit' => array(
         'supports'    => array(
           'git',
           'hg',
         ),
         'nosupport'   => array(
           'svn' => pht('Edit revisions via the web interface when using SVN.'),
         ),
         'help' => pht(
           'When updating a revision under git, edit revision information '.
           'before updating.'),
       ),
       'raw' => array(
         'help' => pht(
           'Read diff from stdin, not from the working copy. This disables '.
           'many Arcanist/Phabricator features which depend on having access '.
           'to the working copy.'),
         'conflicts' => array(
           'apply-patches'       => pht('%s disables lint.', '--raw'),
           'never-apply-patches' => pht('%s disables lint.', '--raw'),
 
           'create'              => pht(
             '%s and %s both need stdin. Use %s.',
             '--raw',
             '--create',
             '--raw-command'),
           'edit'                => pht(
             '%s and %s both need stdin. Use %s.',
             '--raw',
             '--edit',
             '--raw-command'),
           'raw-command'         => null,
         ),
       ),
       'raw-command' => array(
         'param' => 'command',
         'help' => pht(
           'Generate diff by executing a specified command, not from the '.
           'working copy. This disables many Arcanist/Phabricator features '.
           'which depend on having access to the working copy.'),
         'conflicts' => array(
           'apply-patches'       => pht('%s disables lint.', '--raw-command'),
           'never-apply-patches' => pht('%s disables lint.', '--raw-command'),
         ),
       ),
       'create' => array(
         'help' => pht('Always create a new revision.'),
         'conflicts' => array(
           'edit'    => pht(
             '%s can not be used with %s.',
             '--create',
             '--edit'),
           'only' => pht(
             '%s can not be used with %s.',
             '--create',
             '--only'),
           'update'  => pht(
             '%s can not be used with %s.',
             '--create',
             '--update'),
         ),
       ),
       'update' => array(
         'param' => 'revision_id',
         'help'  => pht('Always update a specific revision.'),
       ),
       'draft' => array(
         'help' => pht(
           'Create a draft revision so you can look over your changes before '.
           'involving anyone else. Other users will not be notified about the '.
           'revision until you later use "Request Review" to publish it. You '.
           'can still share the draft by giving someone the link.'),
         'conflicts' => array(
           'edit' => null,
           'only' => null,
           'update' => null,
         ),
       ),
       'nounit' => array(
         'help' => pht('Do not run unit tests.'),
       ),
       'nolint' => array(
         'help' => pht('Do not run lint.'),
         'conflicts' => array(
           'apply-patches' => pht('%s suppresses lint.', '--nolint'),
           'never-apply-patches' => pht('%s suppresses lint.', '--nolint'),
         ),
       ),
       'only' => array(
         'help' => pht(
           'Instead of creating or updating a revision, only create a diff, '.
           'which you may later attach to a revision.'),
         'conflicts' => array(
           'edit'      => pht('%s does affect revisions.', '--only'),
           'message'   => pht('%s does not update any revision.', '--only'),
         ),
       ),
       'allow-untracked' => array(
         'help' => pht('Skip checks for untracked files in the working copy.'),
       ),
       'apply-patches' => array(
         'help' => pht(
           'Apply patches suggested by lint to the working copy without '.
           'prompting.'),
         'conflicts' => array(
           'never-apply-patches' => true,
         ),
         'passthru' => array(
           'lint' => true,
         ),
       ),
       'never-apply-patches' => array(
         'help' => pht('Never apply patches suggested by lint.'),
         'conflicts' => array(
           'apply-patches' => true,
         ),
         'passthru' => array(
           'lint' => true,
         ),
       ),
       'amend-all' => array(
         'help' => pht(
           'When linting git repositories, amend HEAD with all patches '.
           'suggested by lint without prompting.'),
         'passthru' => array(
           'lint' => true,
         ),
       ),
       'amend-autofixes' => array(
         'help' => pht(
           'When linting git repositories, amend HEAD with autofix '.
           'patches suggested by lint without prompting.'),
         'passthru' => array(
           'lint' => true,
         ),
       ),
       'add-all' => array(
         'short' => 'a',
         'help' => pht(
           'Automatically add all unstaged and uncommitted '.
           'files to the commit.'),
       ),
       'json' => array(
         'help' => pht(
           'Emit machine-readable JSON. EXPERIMENTAL! Probably does not work!'),
       ),
       'no-amend' => array(
         'help' => pht(
           'Never amend commits in the working copy with lint patches.'),
       ),
       'uncommitted' => array(
         'help' => pht('Suppress warning about uncommitted changes.'),
         'supports' => array(
           'hg',
         ),
       ),
       'verbatim' => array(
         'help' => pht(
           'When creating a revision, try to use the working copy commit '.
           'message verbatim, without prompting to edit it. When updating a '.
           'revision, update some fields from the local commit message.'),
         'supports' => array(
           'hg',
           'git',
         ),
         'conflicts' => array(
           'update'              => true,
           'only' => true,
           'raw'                 => true,
           'raw-command'         => true,
           'message-file'        => true,
         ),
       ),
       'reviewers' => array(
         'param' => 'usernames',
         'help' => pht('When creating a revision, add reviewers.'),
         'conflicts' => array(
           'only' => true,
           'update'  => true,
         ),
       ),
       'cc' => array(
         'param' => 'usernames',
         'help' => pht('When creating a revision, add CCs.'),
         'conflicts' => array(
           'only' => true,
           'update'  => true,
         ),
       ),
       'skip-binaries' => array(
         'help'  => pht('Do not upload binaries (like images).'),
       ),
       'skip-staging' => array(
         'help' => pht('Do not copy changes to the staging area.'),
       ),
       'base' => array(
         'param' => 'rules',
         'help'  => pht('Additional rules for determining base revision.'),
         'nosupport' => array(
           'svn' => pht('Subversion does not use base commits.'),
         ),
         'supports' => array('git', 'hg'),
       ),
       'coverage' => array(
         'help' => pht('Always enable coverage information.'),
         'conflicts' => array(
           'no-coverage' => null,
         ),
         'passthru' => array(
           'unit' => true,
         ),
       ),
       'no-coverage' => array(
         'help' => pht('Always disable coverage information.'),
         'passthru' => array(
           'unit' => true,
         ),
       ),
       'browse' => array(
         'help' => pht(
           'After creating a diff or revision, open it in a web browser.'),
       ),
       '*' => 'paths',
       'head' => array(
         'param' => 'commit',
         'help' => pht(
           'Specify the end of the commit range. This disables many '.
           'Arcanist/Phabricator features which depend on having access to '.
           'the working copy.'),
         'supports' => array('git'),
         'nosupport' => array(
           'svn' => pht('Subversion does not support commit ranges.'),
           'hg' => pht('Mercurial does not support %s yet.', '--head'),
         ),
       ),
     );
 
     return $arguments;
   }
 
   public function isRawDiffSource() {
     return $this->getArgument('raw') || $this->getArgument('raw-command');
   }
 
   public function run() {
     $this->console = PhutilConsole::getConsole();
 
     $this->runRepositoryAPISetup();
     $this->runDiffSetupBasics();
 
     $commit_message = $this->buildCommitMessage();
 
     $this->dispatchEvent(
       ArcanistEventType::TYPE_DIFF_DIDBUILDMESSAGE,
       array(
         'message' => $commit_message,
       ));
 
     if (!$this->shouldOnlyCreateDiff()) {
       $revision = $this->buildRevisionFromCommitMessage($commit_message);
     }
 
     $data = $this->runLintUnit();
 
     $lint_result = $data['lintResult'];
     $this->unresolvedLint = $data['unresolvedLint'];
     $unit_result = $data['unitResult'];
     $this->testResults = $data['testResults'];
 
     $changes = $this->generateChanges();
     if (!$changes) {
       throw new ArcanistUsageException(
         pht('There are no changes to generate a diff from!'));
     }
 
     $diff_spec = array(
       'changes' => mpull($changes, 'toDictionary'),
       'lintStatus' => $this->getLintStatus($lint_result),
       'unitStatus' => $this->getUnitStatus($unit_result),
     ) + $this->buildDiffSpecification();
 
     $conduit = $this->getConduit();
     $diff_info = $conduit->callMethodSynchronous(
       'differential.creatediff',
       $diff_spec);
 
     $this->diffID = $diff_info['diffid'];
 
     $event = $this->dispatchEvent(
       ArcanistEventType::TYPE_DIFF_WASCREATED,
       array(
         'diffID' => $diff_info['diffid'],
         'lintResult' => $lint_result,
         'unitResult' => $unit_result,
       ));
 
     $this->submitChangesToStagingArea($this->diffID);
 
     $phid = idx($diff_info, 'phid');
     if ($phid) {
       $this->hitAutotargets = $this->updateAutotargets(
         $phid,
         $unit_result);
     }
 
     $this->updateLintDiffProperty();
     $this->updateUnitDiffProperty();
     $this->updateLocalDiffProperty();
     $this->updateOntoDiffProperty();
     $this->resolveDiffPropertyUpdates();
 
     $output_json = $this->getArgument('json');
 
     if ($this->shouldOnlyCreateDiff()) {
       if (!$output_json) {
         echo phutil_console_format(
           "%s\n        **%s** __%s__\n\n",
           pht('Created a new Differential diff:'),
           pht('Diff URI:'),
           $diff_info['uri']);
       } else {
         $human = ob_get_clean();
         echo json_encode(array(
           'diffURI' => $diff_info['uri'],
           'diffID'  => $this->getDiffID(),
           'human'   => $human,
         ))."\n";
         ob_start();
       }
 
       if ($this->shouldOpenCreatedObjectsInBrowser()) {
         $this->openURIsInBrowser(array($diff_info['uri']));
       }
     } else {
       $is_draft = $this->getArgument('draft');
       $revision['diffid'] = $this->getDiffID();
 
       if ($commit_message->getRevisionID()) {
         if ($is_draft) {
           // TODO: In at least some cases, we could raise this earlier in the
           // workflow to save users some time before the workflow aborts.
           if ($this->revisionIsDraft) {
             $this->writeWarn(
               pht('ALREADY A DRAFT'),
               pht(
                 'You are updating a revision ("%s") with the "--draft" flag, '.
                 'but this revision is already a draft. You only need to '.
                 'provide the "--draft" flag when creating a revision. Draft '.
                 'revisions are not published until you explicitly request '.
                 'review from the web UI.',
                 $commit_message->getRevisionMonogram()));
           } else {
             throw new ArcanistUsageException(
               pht(
                 'You are updating a revision ("%s") with the "--draft" flag, '.
                 'but this revision has already been published for review. '.
                 'You can not turn a revision back into a draft once it has '.
                 'been published.',
                 $commit_message->getRevisionMonogram()));
           }
         }
 
         $result = $conduit->callMethodSynchronous(
           'differential.updaterevision',
           $revision);
 
         foreach (array('edit-messages.json', 'update-messages.json') as $file) {
           $messages = $this->readScratchJSONFile($file);
           unset($messages[$revision['id']]);
           $this->writeScratchJSONFile($file, $messages);
         }
 
         $result_uri = $result['uri'];
         $result_id = $result['revisionid'];
 
         echo pht('Updated an existing Differential revision:')."\n";
       } else {
         // NOTE: We're either using "differential.revision.edit" (preferred)
         // if we can, or falling back to "differential.createrevision"
         // (the older way) if not.
 
         $xactions = $this->revisionTransactions;
         if ($xactions) {
           $xactions[] = array(
             'type' => 'update',
             'value' => $diff_info['phid'],
           );
 
           if ($is_draft) {
             $xactions[] = array(
               'type' => 'draft',
               'value' => true,
             );
           }
 
           $result = $conduit->callMethodSynchronous(
             'differential.revision.edit',
             array(
               'transactions' => $xactions,
             ));
 
           $result_id = idxv($result, array('object', 'id'));
           if (!$result_id) {
             throw new Exception(
               pht(
                 'Expected a revision ID to be returned by '.
                 '"differential.revision.edit".'));
           }
 
           // TODO: This is hacky, but we don't currently receive a URI back
           // from "differential.revision.edit".
           $result_uri = id(new PhutilURI($this->getConduitURI()))
             ->setPath('/D'.$result_id);
         } else {
           if ($is_draft) {
             throw new ArcanistUsageException(
               pht(
                 'You have specified "--draft", but the version of Phabricator '.
                 'on the server is too old to support draft revisions. Omit '.
                 'the flag or upgrade the server software.'));
           }
 
           $revision = $this->dispatchWillCreateRevisionEvent($revision);
 
           $result = $conduit->callMethodSynchronous(
             'differential.createrevision',
             $revision);
 
           $result_uri = $result['uri'];
           $result_id = $result['revisionid'];
         }
 
         $revised_message = $conduit->callMethodSynchronous(
           'differential.getcommitmessage',
           array(
             'revision_id' => $result_id,
           ));
 
         if ($this->shouldAmend()) {
           $repository_api = $this->getRepositoryAPI();
           if ($repository_api->supportsAmend()) {
             echo pht('Updating commit message...')."\n";
             $repository_api->amendCommit($revised_message);
           } else {
             echo pht(
               'Commit message was not amended. Amending commit message is '.
               'only supported in git and hg (version 2.2 or newer)');
           }
         }
 
         echo pht('Created a new Differential revision:')."\n";
       }
 
       $uri = $result_uri;
       echo phutil_console_format(
         "        **%s** __%s__\n\n",
         pht('Revision URI:'),
         $uri);
 
       if ($this->shouldOpenCreatedObjectsInBrowser()) {
         $this->openURIsInBrowser(array($uri));
       }
     }
 
     echo pht('Included changes:')."\n";
     foreach ($changes as $change) {
       echo '  '.$change->renderTextSummary()."\n";
     }
 
     if ($output_json) {
       ob_get_clean();
     }
 
     $this->removeScratchFile('create-message');
 
     return 0;
   }
 
   private function runRepositoryAPISetup() {
     if (!$this->requiresRepositoryAPI()) {
       return;
     }
 
     $repository_api = $this->getRepositoryAPI();
 
     $repository_api->setBaseCommitArgumentRules(
       $this->getArgument('base', ''));
 
     if ($repository_api->supportsCommitRanges()) {
       $this->parseBaseCommitArgument($this->getArgument('paths'));
     }
 
     $head_commit = $this->getArgument('head');
     if ($head_commit !== null) {
       $repository_api->setHeadCommit($head_commit);
     }
 
   }
 
   private function runDiffSetupBasics() {
     $output_json = $this->getArgument('json');
     if ($output_json) {
       // TODO: We should move this to a higher-level and put an indirection
       // layer between echoing stuff and stdout.
       ob_start();
     }
 
     if ($this->requiresWorkingCopy()) {
       $repository_api = $this->getRepositoryAPI();
       if ($this->getArgument('add-all')) {
         $this->setCommitMode(self::COMMIT_ENABLE);
       } else if ($this->getArgument('uncommitted')) {
         $this->setCommitMode(self::COMMIT_DISABLE);
       } else {
         $this->setCommitMode(self::COMMIT_ALLOW);
       }
       if ($repository_api instanceof ArcanistSubversionAPI) {
         $repository_api->limitStatusToPaths($this->getArgument('paths'));
       }
       if (!$this->getArgument('head')) {
         $this->requireCleanWorkingCopy();
       }
     }
 
     $this->dispatchEvent(
       ArcanistEventType::TYPE_DIFF_DIDCOLLECTCHANGES,
       array());
   }
 
   private function buildRevisionFromCommitMessage(
     ArcanistDifferentialCommitMessage $message) {
 
     $conduit = $this->getConduit();
 
     $revision_id = $message->getRevisionID();
     $revision = array(
       'fields' => $message->getFields(),
     );
     $xactions = $message->getTransactions();
 
     if ($revision_id) {
 
       // With '--verbatim', pass the (possibly modified) local fields. This
       // allows the user to edit some fields (like "title" and "summary")
       // locally without '--edit' and have changes automatically synchronized.
       // Without '--verbatim', we do not update the revision to reflect local
       // commit message changes.
       if ($this->getArgument('verbatim')) {
         $use_fields = $message->getFields();
       } else {
         $use_fields = array();
       }
 
       $should_edit = $this->getArgument('edit');
       $edit_messages = $this->readScratchJSONFile('edit-messages.json');
       $remote_corpus = idx($edit_messages, $revision_id);
 
       if (!$should_edit || !$remote_corpus || $use_fields) {
         if ($this->commitMessageFromRevision) {
           $remote_corpus = $this->commitMessageFromRevision;
         } else {
           $remote_corpus = $conduit->callMethodSynchronous(
             'differential.getcommitmessage',
             array(
               'revision_id' => $revision_id,
               'edit'        => 'edit',
               'fields'      => $use_fields,
             ));
         }
       }
 
       if ($should_edit) {
         $edited = $this->newInteractiveEditor($remote_corpus)
           ->setName('differential-edit-revision-info')
           ->editInteractively();
         if ($edited != $remote_corpus) {
           $remote_corpus = $edited;
           $edit_messages[$revision_id] = $remote_corpus;
           $this->writeScratchJSONFile('edit-messages.json', $edit_messages);
         }
       }
 
       if ($this->commitMessageFromRevision == $remote_corpus) {
         $new_message = $message;
       } else {
         $remote_corpus = ArcanistCommentRemover::removeComments(
           $remote_corpus);
         $new_message = ArcanistDifferentialCommitMessage::newFromRawCorpus(
           $remote_corpus);
         $new_message->pullDataFromConduit($conduit);
       }
 
       $revision['fields'] = $new_message->getFields();
       $xactions = $new_message->getTransactions();
 
       $revision['id'] = $revision_id;
       $this->revisionID = $revision_id;
 
       $revision['message'] = $this->getArgument('message');
       if (!strlen($revision['message'])) {
         $update_messages = $this->readScratchJSONFile('update-messages.json');
 
         $update_messages[$revision_id] = $this->getUpdateMessage(
           $revision['fields'],
           idx($update_messages, $revision_id));
 
         $revision['message'] = ArcanistCommentRemover::removeComments(
           $update_messages[$revision_id]);
         if (!strlen(trim($revision['message']))) {
           throw new ArcanistUserAbortException();
         }
 
         $this->writeScratchJSONFile('update-messages.json', $update_messages);
       }
     }
 
     $this->revisionTransactions = $xactions;
 
     return $revision;
   }
 
   protected function shouldOnlyCreateDiff() {
     if ($this->getArgument('create')) {
       return false;
     }
 
     if ($this->getArgument('update')) {
       return false;
     }
 
     if ($this->isRawDiffSource()) {
       return true;
     }
 
     return $this->getArgument('only');
   }
 
   private function generateAffectedPaths() {
     if ($this->isRawDiffSource()) {
       return array();
     }
 
     $repository_api = $this->getRepositoryAPI();
     if ($repository_api instanceof ArcanistSubversionAPI) {
       $file_list = new FileList($this->getArgument('paths', array()));
       $paths = $repository_api->getSVNStatus($externals = true);
       foreach ($paths as $path => $mask) {
         if (!$file_list->contains($repository_api->getPath($path), true)) {
           unset($paths[$path]);
         }
       }
 
       $warn_externals = array();
       foreach ($paths as $path => $mask) {
         $any_mod = ($mask & ArcanistRepositoryAPI::FLAG_ADDED) ||
                    ($mask & ArcanistRepositoryAPI::FLAG_MODIFIED) ||
                    ($mask & ArcanistRepositoryAPI::FLAG_DELETED);
         if ($mask & ArcanistRepositoryAPI::FLAG_EXTERNALS) {
           unset($paths[$path]);
           if ($any_mod) {
             $warn_externals[] = $path;
           }
         }
       }
 
       if ($warn_externals && !$this->hasWarnedExternals) {
         echo phutil_console_format(
           "%s\n\n%s\n\n",
           pht(
             "The working copy includes changes to '%s' paths. These ".
             "changes will not be included in the diff because SVN can not ".
             "commit 'svn:externals' changes alongside normal changes.",
             'svn:externals'),
           pht(
             "Modified '%s' files:",
             'svn:externals'),
           phutil_console_wrap(implode("\n", $warn_externals), 8));
         $prompt = pht('Generate a diff (with just local changes) anyway?');
         if (!phutil_console_confirm($prompt)) {
           throw new ArcanistUserAbortException();
         } else {
           $this->hasWarnedExternals = true;
         }
       }
 
     } else {
       $paths = $repository_api->getWorkingCopyStatus();
     }
 
     foreach ($paths as $path => $mask) {
       if ($mask & ArcanistRepositoryAPI::FLAG_UNTRACKED) {
         unset($paths[$path]);
       }
     }
 
     return $paths;
   }
 
 
   protected function generateChanges() {
     $parser = $this->newDiffParser();
 
     $is_raw = $this->isRawDiffSource();
     if ($is_raw) {
 
       if ($this->getArgument('raw')) {
         fwrite(STDERR, pht('Reading diff from stdin...')."\n");
         $raw_diff = file_get_contents('php://stdin');
       } else if ($this->getArgument('raw-command')) {
         list($raw_diff) = execx('%C', $this->getArgument('raw-command'));
       } else {
         throw new Exception(pht('Unknown raw diff source.'));
       }
 
       $changes = $parser->parseDiff($raw_diff);
       foreach ($changes as $key => $change) {
         // Remove "message" changes, e.g. from "git show".
         if ($change->getType() == ArcanistDiffChangeType::TYPE_MESSAGE) {
           unset($changes[$key]);
         }
       }
       return $changes;
     }
 
     $repository_api = $this->getRepositoryAPI();
 
     if ($repository_api instanceof ArcanistSubversionAPI) {
       $paths = $this->generateAffectedPaths();
       $this->primeSubversionWorkingCopyData($paths);
 
       // Check to make sure the user is diffing from a consistent base revision.
       // This is mostly just an abuse sanity check because it's silly to do this
       // and makes the code more difficult to effectively review, but it also
       // affects patches and makes them nonportable.
       $bases = $repository_api->getSVNBaseRevisions();
 
       // Remove all files with baserev "0"; these files are new.
       foreach ($bases as $path => $baserev) {
         if ($bases[$path] <= 0) {
           unset($bases[$path]);
         }
       }
 
       if ($bases) {
         $rev = reset($bases);
 
         $revlist = array();
         foreach ($bases as $path => $baserev) {
           $revlist[] = '    '.pht('Revision %s, %s', $baserev, $path);
         }
         $revlist = implode("\n", $revlist);
 
         foreach ($bases as $path => $baserev) {
           if ($baserev !== $rev) {
             throw new ArcanistUsageException(
               pht(
                 "Base revisions of changed paths are mismatched. Update all ".
                 "paths to the same base revision before creating a diff: ".
                 "\n\n%s",
                 $revlist));
           }
         }
 
         // If you have a change which affects several files, all of which are
         // at a consistent base revision, treat that revision as the effective
         // base revision. The use case here is that you made a change to some
         // file, which updates it to HEAD, but want to be able to change it
         // again without updating the entire working copy. This is a little
         // sketchy but it arises in Facebook Ops workflows with config files and
         // doesn't have any real material tradeoffs (e.g., these patches are
         // perfectly applyable).
         $repository_api->overrideSVNBaseRevisionNumber($rev);
       }
 
       $changes = $parser->parseSubversionDiff(
         $repository_api,
         $paths);
     } else if ($repository_api instanceof ArcanistGitAPI) {
       $diff = $repository_api->getFullGitDiff(
         $repository_api->getBaseCommit(),
         $repository_api->getHeadCommit());
       if (!strlen($diff)) {
         throw new ArcanistUsageException(
           pht('No changes found. (Did you specify the wrong commit range?)'));
       }
       $changes = $parser->parseDiff($diff);
     } else if ($repository_api instanceof ArcanistMercurialAPI) {
       $diff = $repository_api->getFullMercurialDiff();
       if (!strlen($diff)) {
         throw new ArcanistUsageException(
           pht('No changes found. (Did you specify the wrong commit range?)'));
       }
       $changes = $parser->parseDiff($diff);
     } else {
       throw new Exception(pht('Repository API is not supported.'));
     }
 
     $limit = 1024 * 1024 * 4;
     foreach ($changes as $change) {
       $size = 0;
       foreach ($change->getHunks() as $hunk) {
         $size += strlen($hunk->getCorpus());
       }
       if ($size > $limit) {
         $byte_warning = pht(
           "Diff for '%s' with context is %s bytes in length. ".
           "Generally, source changes should not be this large.",
           $change->getCurrentPath(),
           new PhutilNumber($size));
         if ($repository_api instanceof ArcanistSubversionAPI) {
           throw new ArcanistUsageException(
             $byte_warning.' '.
             pht(
               "If the file is not a text file, mark it as binary with:".
               "\n\n  $ %s\n",
               'svn propset svn:mime-type application/octet-stream <filename>'));
         } else {
           $confirm = $byte_warning.' '.pht(
             "If the file is not a text file, you can mark it 'binary'. ".
             "Mark this file as 'binary' and continue?");
           if (phutil_console_confirm($confirm)) {
             $change->convertToBinaryChange($repository_api);
           } else {
             throw new ArcanistUsageException(
               pht('Aborted generation of gigantic diff.'));
           }
         }
       }
     }
 
     $utf8_problems = array();
     foreach ($changes as $change) {
       foreach ($change->getHunks() as $hunk) {
         $corpus = $hunk->getCorpus();
         if (!phutil_is_utf8($corpus)) {
 
           // If this corpus is heuristically binary, don't try to convert it.
           // mb_check_encoding() and mb_convert_encoding() are both very very
           // liberal about what they're willing to process.
           $is_binary = ArcanistDiffUtils::isHeuristicBinaryFile($corpus);
           if (!$is_binary) {
 
             try {
               $try_encoding = $this->getRepositoryEncoding();
             } catch (ConduitClientException $e) {
               if ($e->getErrorCode() == 'ERR-BAD-ARCANIST-PROJECT') {
                 echo phutil_console_wrap(
                   pht('Lookup of encoding in arcanist project failed: %s',
                       $e->getMessage())."\n");
               } else {
                 throw $e;
               }
             }
 
             if ($try_encoding) {
               $corpus = phutil_utf8_convert($corpus, 'UTF-8', $try_encoding);
               $name = $change->getCurrentPath();
               if (phutil_is_utf8($corpus)) {
                 $this->writeStatusMessage(
                   pht(
                     "Converted a '%s' hunk from '%s' to UTF-8.\n",
                     $name,
                     $try_encoding));
                 $hunk->setCorpus($corpus);
                 continue;
               }
             }
           }
           $utf8_problems[] = $change;
           break;
         }
       }
     }
 
     // If there are non-binary files which aren't valid UTF-8, warn the user
     // and treat them as binary changes. See D327 for discussion of why Arcanist
     // has this behavior.
     if ($utf8_problems) {
       $utf8_warning =
         sprintf(
           "%s\n\n%s\n\n    %s\n",
           pht(
             'This diff includes %s file(s) which are not valid UTF-8 (they '.
             'contain invalid byte sequences). You can either stop this '.
             'workflow and fix these files, or continue. If you continue, '.
             'these files will be marked as binary.',
             phutil_count($utf8_problems)),
           pht(
             "You can learn more about how Phabricator handles character ".
             "encodings (and how to configure encoding settings and detect and ".
             "correct encoding problems) by reading 'User Guide: UTF-8 and ".
             "Character Encoding' in the Phabricator documentation."),
           pht(
             '%s AFFECTED FILE(S)',
             phutil_count($utf8_problems)));
       $confirm = pht(
         'Do you want to mark these %s file(s) as binary and continue?',
         phutil_count($utf8_problems));
 
       echo phutil_console_format(
         "**%s**\n",
         pht('Invalid Content Encoding (Non-UTF8)'));
       echo phutil_console_wrap($utf8_warning);
 
       $file_list = mpull($utf8_problems, 'getCurrentPath');
       $file_list = '    '.implode("\n    ", $file_list);
       echo $file_list;
 
       if (!phutil_console_confirm($confirm, $default_no = false)) {
         throw new ArcanistUsageException(pht('Aborted workflow to fix UTF-8.'));
       } else {
         foreach ($utf8_problems as $change) {
           $change->convertToBinaryChange($repository_api);
         }
       }
     }
 
     $this->uploadFilesForChanges($changes);
 
     return $changes;
   }
 
   private function getGitParentLogInfo() {
     $info = array(
       'parent'        => null,
       'base_revision' => null,
       'base_path'     => null,
       'uuid'          => null,
     );
 
     $repository_api = $this->getRepositoryAPI();
 
     $parser = $this->newDiffParser();
     $history_messages = $repository_api->getGitHistoryLog();
     if (!$history_messages) {
       // This can occur on the initial commit.
       return $info;
     }
     $history_messages = $parser->parseDiff($history_messages);
 
     foreach ($history_messages as $key => $change) {
       try {
         $message = ArcanistDifferentialCommitMessage::newFromRawCorpus(
           $change->getMetadata('message'));
         if ($message->getRevisionID() && $info['parent'] === null) {
           $info['parent'] = $message->getRevisionID();
         }
         if ($message->getGitSVNBaseRevision() &&
             $info['base_revision'] === null) {
           $info['base_revision'] = $message->getGitSVNBaseRevision();
           $info['base_path']     = $message->getGitSVNBasePath();
         }
         if ($message->getGitSVNUUID()) {
           $info['uuid'] = $message->getGitSVNUUID();
         }
         if ($info['parent'] && $info['base_revision']) {
           break;
         }
       } catch (ArcanistDifferentialCommitMessageParserException $ex) {
         // Ignore.
       } catch (ArcanistUsageException $ex) {
         // Ignore an invalid Differential Revision field in the parent commit
       }
     }
 
     return $info;
   }
 
   protected function primeSubversionWorkingCopyData($paths) {
     $repository_api = $this->getRepositoryAPI();
 
     $futures = array();
     $targets = array();
     foreach ($paths as $path => $mask) {
       $futures[] = $repository_api->buildDiffFuture($path);
       $targets[] = array('command' => 'diff', 'path' => $path);
       $futures[] = $repository_api->buildInfoFuture($path);
       $targets[] = array('command' => 'info', 'path' => $path);
     }
 
     $futures = id(new FutureIterator($futures))
       ->limit(8);
     foreach ($futures as $key => $future) {
       $target = $targets[$key];
       if ($target['command'] == 'diff') {
         $repository_api->primeSVNDiffResult(
           $target['path'],
           $future->resolve());
       } else {
         $repository_api->primeSVNInfoResult(
           $target['path'],
           $future->resolve());
       }
     }
   }
 
   private function shouldAmend() {
     if ($this->isRawDiffSource()) {
       return false;
     }
 
     if ($this->getArgument('no-amend')) {
       return false;
     }
 
     if ($this->getArgument('head') !== null) {
       return false;
     }
 
     // Run this last: with --raw or --raw-command, we won't have a repository
     // API.
     if ($this->isHistoryImmutable()) {
       return false;
     }
 
     return true;
   }
 
 
 /* -(  Lint and Unit Tests  )------------------------------------------------ */
 
 
   /**
    * @task lintunit
    */
   private function runLintUnit() {
     $lint_result = $this->runLint();
     $unit_result = $this->runUnit();
     return array(
       'lintResult' => $lint_result,
       'unresolvedLint' => $this->unresolvedLint,
       'unitResult' => $unit_result,
       'testResults' => $this->testResults,
     );
   }
 
 
   /**
    * @task lintunit
    */
   private function runLint() {
     if ($this->getArgument('nolint') ||
         $this->isRawDiffSource() ||
         $this->getArgument('head')) {
       return ArcanistLintWorkflow::RESULT_SKIP;
     }
 
     $repository_api = $this->getRepositoryAPI();
 
     $this->console->writeOut("%s\n", pht('Linting...'));
     try {
       $argv = $this->getPassthruArgumentsAsArgv('lint');
       if ($repository_api->supportsCommitRanges()) {
         $argv[] = '--rev';
         $argv[] = $repository_api->getBaseCommit();
       }
 
       $lint_workflow = $this->buildChildWorkflow('lint', $argv);
 
       if ($this->shouldAmend()) {
         // TODO: We should offer to create a checkpoint commit.
         $lint_workflow->setShouldAmendChanges(true);
       }
 
       $lint_result = $lint_workflow->run();
 
       switch ($lint_result) {
         case ArcanistLintWorkflow::RESULT_OKAY:
           $this->console->writeOut(
             "<bg:green>** %s **</bg> %s\n",
             pht('LINT OKAY'),
             pht('No lint problems.'));
           break;
         case ArcanistLintWorkflow::RESULT_WARNINGS:
           $this->console->writeOut(
             "<bg:yellow>** %s **</bg> %s\n",
             pht('LINT MESSAGES'),
             pht('Lint issued unresolved warnings.'));
           break;
         case ArcanistLintWorkflow::RESULT_ERRORS:
           $this->console->writeOut(
             "<bg:red>** %s **</bg> %s\n",
             pht('LINT ERRORS'),
             pht('Lint raised errors!'));
           break;
       }
 
       $this->unresolvedLint = array();
       foreach ($lint_workflow->getUnresolvedMessages() as $message) {
         $this->unresolvedLint[] = $message->toDictionary();
       }
 
       return $lint_result;
     } catch (ArcanistNoEngineException $ex) {
       $this->console->writeOut(
         "%s\n",
         pht('No lint engine configured for this project.'));
     } catch (ArcanistNoEffectException $ex) {
       $this->console->writeOut("%s\n", $ex->getMessage());
     }
 
     return null;
   }
 
 
   /**
    * @task lintunit
    */
   private function runUnit() {
     if ($this->getArgument('nounit') ||
         $this->isRawDiffSource() ||
         $this->getArgument('head')) {
       return ArcanistUnitWorkflow::RESULT_SKIP;
     }
 
     $repository_api = $this->getRepositoryAPI();
 
     $this->console->writeOut("%s\n", pht('Running unit tests...'));
     try {
       $argv = $this->getPassthruArgumentsAsArgv('unit');
       if ($repository_api->supportsCommitRanges()) {
         $argv[] = '--rev';
         $argv[] = $repository_api->getBaseCommit();
       }
       $unit_workflow = $this->buildChildWorkflow('unit', $argv);
       $unit_result = $unit_workflow->run();
 
       switch ($unit_result) {
         case ArcanistUnitWorkflow::RESULT_OKAY:
           $this->console->writeOut(
             "<bg:green>** %s **</bg> %s\n",
             pht('UNIT OKAY'),
             pht('No unit test failures.'));
           break;
         case ArcanistUnitWorkflow::RESULT_UNSOUND:
           $continue = phutil_console_confirm(
             pht(
               'Unit test results included failures, but all failing tests '.
               'are known to be unsound. Ignore unsound test failures?'));
           if (!$continue) {
             throw new ArcanistUserAbortException();
           }
 
           echo phutil_console_format(
             "<bg:yellow>** %s **</bg> %s\n",
             pht('UNIT UNSOUND'),
             pht(
               'Unit testing raised errors, but all '.
               'failing tests are unsound.'));
           break;
         case ArcanistUnitWorkflow::RESULT_FAIL:
           $this->console->writeOut(
             "<bg:red>** %s **</bg> %s\n",
             pht('UNIT ERRORS'),
             pht('Unit testing raised errors!'));
           break;
       }
 
       $this->testResults = array();
       foreach ($unit_workflow->getTestResults() as $test) {
         $this->testResults[] = $test->toDictionary();
       }
 
       return $unit_result;
     } catch (ArcanistNoEngineException $ex) {
       $this->console->writeOut(
         "%s\n",
         pht('No unit test engine is configured for this project.'));
     } catch (ArcanistNoEffectException $ex) {
       $this->console->writeOut("%s\n", $ex->getMessage());
     }
 
     return null;
   }
 
   public function getTestResults() {
     return $this->testResults;
   }
 
 
 /* -(  Commit and Update Messages  )----------------------------------------- */
 
 
   /**
    * @task message
    */
   private function buildCommitMessage() {
     if ($this->getArgument('only')) {
       return null;
     }
 
     $is_create = $this->getArgument('create');
     $is_update = $this->getArgument('update');
     $is_raw = $this->isRawDiffSource();
     $is_verbatim = $this->getArgument('verbatim');
 
     if ($is_verbatim) {
       return $this->getCommitMessageFromUser();
     }
 
 
     if (!$is_raw && !$is_create && !$is_update) {
       $repository_api = $this->getRepositoryAPI();
       $revisions = $repository_api->loadWorkingCopyDifferentialRevisions(
         $this->getConduit(),
         array(
           'authors' => array($this->getUserPHID()),
           'status'  => 'status-open',
         ));
       if (!$revisions) {
         $is_create = true;
       } else if (count($revisions) == 1) {
         $revision = head($revisions);
         $is_update = $revision['id'];
       } else {
         throw new ArcanistUsageException(
           pht(
             "There are several revisions which match the working copy:\n\n%s\n".
             "Use '%s' to choose one, or '%s' to create a new revision.",
             $this->renderRevisionList($revisions),
             '--update',
             '--create'));
       }
     }
 
     $message = null;
     if ($is_create) {
       $message_file = $this->getArgument('message-file');
       if ($message_file) {
         return $this->getCommitMessageFromFile($message_file);
       } else {
         return $this->getCommitMessageFromUser();
       }
     } else if ($is_update) {
       $revision_id = $this->normalizeRevisionID($is_update);
       if (!is_numeric($revision_id)) {
         throw new ArcanistUsageException(
           pht(
             'Parameter to %s must be a Differential Revision number.',
             '--update'));
       }
       return $this->getCommitMessageFromRevision($revision_id);
     } else {
       // This is --raw without enough info to create a revision, so force just
       // a diff.
       return null;
     }
   }
 
 
   /**
    * @task message
    */
   private function getCommitMessageFromUser() {
     $conduit = $this->getConduit();
 
     $template = null;
 
     if (!$this->getArgument('verbatim')) {
       $saved = $this->readScratchFile('create-message');
       if ($saved) {
         $where = $this->getReadableScratchFilePath('create-message');
 
         $preview = explode("\n", $saved);
         $preview = array_shift($preview);
         $preview = trim($preview);
         $preview = id(new PhutilUTF8StringTruncator())
           ->setMaximumGlyphs(64)
           ->truncateString($preview);
 
         if ($preview) {
           $preview = pht('Message begins:')."\n\n       {$preview}\n\n";
         } else {
           $preview = null;
         }
 
         echo pht(
           "You have a saved revision message in '%s'.\n%s".
           "You can use this message, or discard it.",
           $where,
           $preview);
 
         $use = phutil_console_confirm(
           pht('Do you want to use this message?'),
           $default_no = false);
         if ($use) {
           $template = $saved;
         } else {
           $this->removeScratchFile('create-message');
         }
       }
     }
 
     $template_is_default = false;
     $notes = array();
     $included = array();
 
     list($fields, $notes, $included_commits) = $this->getDefaultCreateFields();
     if ($template) {
       $fields = array();
       $notes = array();
     } else {
       if (!$fields) {
         $template_is_default = true;
       }
 
       if ($notes) {
         $commit = head($this->getRepositoryAPI()->getLocalCommitInformation());
         $template = $commit['message'];
       } else {
         $template = $conduit->callMethodSynchronous(
           'differential.getcommitmessage',
           array(
             'revision_id' => null,
             'edit'        => 'create',
             'fields'      => $fields,
           ));
       }
     }
 
     $old_message = $template;
 
     $included = array();
     if ($included_commits) {
       foreach ($included_commits as $commit) {
         $included[] = '        '.$commit;
       }
 
       if (!$this->isRawDiffSource()) {
         $message = pht(
           'Included commits in branch %s:',
           $this->getRepositoryAPI()->getBranchName());
       } else {
         $message = pht('Included commits:');
       }
       $included = array_merge(
         array(
           '',
           $message,
           '',
         ),
         $included);
     }
 
     $issues = array_merge(
       array(
         pht('NEW DIFFERENTIAL REVISION'),
         pht('Describe the changes in this new revision.'),
       ),
       $included,
       array(
         '',
         pht(
           'arc could not identify any existing revision in your working copy.'),
         pht('If you intended to update an existing revision, use:'),
         '',
         '  $ arc diff --update <revision>',
       ));
     if ($notes) {
       $issues = array_merge($issues, array(''), $notes);
     }
 
     $done = false;
     $first = true;
     while (!$done) {
       $template = rtrim($template, "\r\n")."\n\n";
       foreach ($issues as $issue) {
         $template .= rtrim('# '.$issue)."\n";
       }
       $template .= "\n";
 
       if ($first && $this->getArgument('verbatim') && !$template_is_default) {
         $new_template = $template;
       } else {
         $new_template = $this->newInteractiveEditor($template)
           ->setName('new-commit')
           ->editInteractively();
       }
       $first = false;
 
       if ($template_is_default && ($new_template == $template)) {
         throw new ArcanistUsageException(pht('Template not edited.'));
       }
 
       $template = ArcanistCommentRemover::removeComments($new_template);
 
       // With --raw-command, we may not have a repository API.
       if ($this->hasRepositoryAPI()) {
         $repository_api = $this->getRepositoryAPI();
         // special check for whether to amend here. optimizes a common git
         // workflow. we can't do this for mercurial because the mq extension
         // is popular and incompatible with hg commit --amend ; see T2011.
         $should_amend = (count($included_commits) == 1 &&
                          $repository_api instanceof ArcanistGitAPI &&
                          $this->shouldAmend());
       } else {
         $should_amend = false;
       }
 
       if ($should_amend) {
         $wrote = (rtrim($old_message) != rtrim($template));
         if ($wrote) {
           $repository_api->amendCommit($template);
           $where = pht('commit message');
         }
       } else {
         $wrote = $this->writeScratchFile('create-message', $template);
         $where = "'".$this->getReadableScratchFilePath('create-message')."'";
       }
 
       try {
         $message = ArcanistDifferentialCommitMessage::newFromRawCorpus(
           $template);
         $message->pullDataFromConduit($conduit);
         $this->validateCommitMessage($message);
         $done = true;
       } catch (ArcanistDifferentialCommitMessageParserException $ex) {
         echo pht('Commit message has errors:')."\n\n";
         $issues = array(pht('Resolve these errors:'));
         foreach ($ex->getParserErrors() as $error) {
           echo phutil_console_wrap("- ".$error."\n", 6);
           $issues[] = '  - '.$error;
         }
         echo "\n";
         echo pht('You must resolve these errors to continue.');
         $again = phutil_console_confirm(
           pht('Do you want to edit the message?'),
           $default_no = false);
         if ($again) {
           // Keep going.
         } else {
           $saved = null;
           if ($wrote) {
             $saved = pht('A copy was saved to %s.', $where);
           }
           throw new ArcanistUsageException(
             pht('Message has unresolved errors.')." {$saved}");
         }
       } catch (Exception $ex) {
         if ($wrote) {
           echo phutil_console_wrap(pht('(Message saved to %s.)', $where)."\n");
         }
         throw $ex;
       }
     }
 
     return $message;
   }
 
 
   /**
    * @task message
    */
   private function getCommitMessageFromFile($file) {
     $conduit = $this->getConduit();
 
     $data = Filesystem::readFile($file);
     $message = ArcanistDifferentialCommitMessage::newFromRawCorpus($data);
     $message->pullDataFromConduit($conduit);
 
     $this->validateCommitMessage($message);
 
     return $message;
   }
 
 
   /**
    * @task message
    */
   private function getCommitMessageFromRevision($revision_id) {
     $id = $revision_id;
 
     $revision = $this->getConduit()->callMethodSynchronous(
       'differential.query',
       array(
         'ids' => array($id),
       ));
     $revision = head($revision);
 
     if (!$revision) {
       throw new ArcanistUsageException(
         pht(
           "Revision '%s' does not exist!",
           $revision_id));
     }
 
     $this->checkRevisionOwnership($revision);
 
     // TODO: Save this status to improve a prompt later. See PHI458. This is
     // extra awful until we move to "differential.revision.search" because
     // the "differential.query" method doesn't return a real draft status for
     // compatibility.
     $this->revisionIsDraft = (idx($revision, 'statusName') === 'Draft');
 
     $message = $this->getConduit()->callMethodSynchronous(
       'differential.getcommitmessage',
       array(
         'revision_id' => $id,
         'edit'        => false,
       ));
     $this->commitMessageFromRevision = $message;
 
     $obj = ArcanistDifferentialCommitMessage::newFromRawCorpus($message);
     $obj->pullDataFromConduit($this->getConduit());
 
     return $obj;
   }
 
 
   /**
    * @task message
    */
   private function validateCommitMessage(
     ArcanistDifferentialCommitMessage $message) {
     $futures = array();
 
     $revision_id = $message->getRevisionID();
     if ($revision_id) {
       $futures['revision'] = $this->getConduit()->callMethod(
         'differential.query',
         array(
           'ids' => array($revision_id),
         ));
     }
 
     $reviewers = $message->getFieldValue('reviewerPHIDs');
     if ($reviewers) {
       $futures['reviewers'] = $this->getConduit()->callMethod(
         'user.query',
         array(
           'phids' => $reviewers,
         ));
     }
 
     foreach (new FutureIterator($futures) as $key => $future) {
       $result = $future->resolve();
       switch ($key) {
         case 'revision':
           if (empty($result)) {
             throw new ArcanistUsageException(
               pht(
                 'There is no revision %s.',
                 "D{$revision_id}"));
           }
           $this->checkRevisionOwnership(head($result));
           break;
         case 'reviewers':
           $away = array();
           foreach ($result as $user) {
             if (idx($user, 'currentStatus') != 'away') {
               continue;
             }
 
             $username = $user['userName'];
             $real_name = $user['realName'];
 
             if (strlen($real_name)) {
               $name = pht('%s (%s)', $username, $real_name);
             } else {
               $name = pht('%s', $username);
             }
 
             $away[] = array(
               'name' => $name,
               'until' => $user['currentStatusUntil'],
             );
           }
 
           if ($away) {
             if (count($away) == count($reviewers)) {
               $earliest_return = min(ipull($away, 'until'));
 
               $message = pht(
                 'All reviewers are away until %s:',
                 date('l, M j Y', $earliest_return));
             } else {
               $message = pht('Some reviewers are currently away:');
             }
 
             echo tsprintf(
               "%s\n\n",
               $message);
 
             $list = id(new PhutilConsoleList());
             foreach ($away as $spec) {
               $list->addItem(
                 pht(
                   '%s (until %s)',
                   $spec['name'],
                   date('l, M j Y', $spec['until'])));
             }
 
             echo tsprintf(
               '%B',
               $list->drawConsoleString());
 
             $confirm = pht('Continue even though reviewers are unavailable?');
             if (!phutil_console_confirm($confirm)) {
               throw new ArcanistUsageException(
                 pht('Specify available reviewers and retry.'));
             }
           }
           break;
       }
     }
 
   }
 
 
   /**
    * @task message
    */
   private function getUpdateMessage(array $fields, $template = '') {
     if ($this->getArgument('raw')) {
       throw new ArcanistUsageException(
         pht(
           "When using '%s' to update a revision, specify an update message ".
           "with '%s'. (Normally, we'd launch an editor to ask you for a ".
           "message, but can not do that because stdin is the diff source.)",
           '--raw',
           '--message'));
     }
 
     // When updating a revision using git without specifying '--message', try
     // to prefill with the message in HEAD if it isn't a template message. The
     // idea is that if you do:
     //
     //  $ git commit -a -m 'fix some junk'
     //  $ arc diff
     //
     // ...you shouldn't have to retype the update message. Similar things apply
     // to Mercurial.
 
     if ($template == '') {
       $comments = $this->getDefaultUpdateMessage();
 
       $template = sprintf(
         "%s\n\n# %s\n#\n# %s\n# %s\n#\n# %s\n#  $ %s\n\n",
         rtrim($comments),
         pht(
           'Updating %s: %s',
           "D{$fields['revisionID']}",
           $fields['title']),
         pht(
           'Enter a brief description of the changes included in this update.'),
         pht('The first line is used as subject, next lines as comment.'),
         pht('If you intended to create a new revision, use:'),
         'arc diff --create');
     }
 
     $comments = $this->newInteractiveEditor($template)
       ->setName('differential-update-comments')
       ->editInteractively();
 
     return $comments;
   }
 
   private function getDefaultCreateFields() {
     $result = array(array(), array(), array());
 
     if ($this->isRawDiffSource()) {
       return $result;
     }
 
     $repository_api = $this->getRepositoryAPI();
     $local = $repository_api->getLocalCommitInformation();
     if ($local) {
       $result = $this->parseCommitMessagesIntoFields($local);
       if ($this->getArgument('create')) {
         unset($result[0]['revisionID']);
       }
     }
 
     $result[0] = $this->dispatchWillBuildEvent($result[0]);
 
     return $result;
   }
 
   /**
    * Convert a list of commits from `getLocalCommitInformation()` into
    * a format usable by arc to create a new diff. Specifically, we emit:
    *
    *   - A dictionary of commit message fields.
    *   - A list of errors encountered while parsing the messages.
    *   - A human-readable list of the commits themselves.
    *
    * For example, if the user runs "arc diff HEAD^^^" and selects a diff range
    * which includes several diffs, we attempt to merge them somewhat
    * intelligently into a single message, because we can only send one
    * "Summary:", "Reviewers:", etc., field to Differential. We also return
    * errors (e.g., if the user typed a reviewer name incorrectly) and a
    * summary of the commits themselves.
    *
    * @param dict  Local commit information.
    * @return list Complex output, see summary.
    * @task message
    */
   private function parseCommitMessagesIntoFields(array $local) {
     $conduit = $this->getConduit();
     $local = ipull($local, null, 'commit');
 
     // If the user provided "--reviewers" or "--ccs", add a faux message to
     // the list with the implied fields.
 
     $faux_message = array();
     if ($this->getArgument('reviewers')) {
       $faux_message[] = pht('Reviewers: %s', $this->getArgument('reviewers'));
     }
     if ($this->getArgument('cc')) {
       $faux_message[] = pht('CC: %s', $this->getArgument('cc'));
     }
 
     // NOTE: For now, this isn't a real field, so it just ends up as the first
     // part of the summary.
     $depends_ref = $this->getDependsOnRevisionRef();
     if ($depends_ref) {
       $faux_message[] = pht(
         'Depends on %s. ',
         $depends_ref->getMonogram());
     }
 
     // See T12069. After T10312, the first line of a message is always parsed
     // as a title. Add a placeholder so "Reviewers" and "CC" are never the
     // first line.
     $placeholder_title = pht('<placeholder>');
 
     if ($faux_message) {
       array_unshift($faux_message, $placeholder_title);
       $faux_message = implode("\n\n", $faux_message);
       $local = array(
         '(Flags)     ' => array(
           'message' => $faux_message,
           'summary' => pht('Command-Line Flags'),
         ),
       ) + $local;
     }
 
     // Build a human-readable list of the commits, so we can show the user which
     // commits are included in the diff.
     $included = array();
     foreach ($local as $hash => $info) {
       $included[] = substr($hash, 0, 12).' '.$info['summary'];
     }
 
     // Parse all of the messages into fields.
     $messages = array();
     foreach ($local as $hash => $info) {
       $text = $info['message'];
       $obj = ArcanistDifferentialCommitMessage::newFromRawCorpus($text);
       $messages[$hash] = $obj;
     }
 
     $notes = array();
     $fields = array();
     foreach ($messages as $hash => $message) {
       try {
         $message->pullDataFromConduit($conduit, $partial = true);
         $fields[$hash] = $message->getFields();
       } catch (ArcanistDifferentialCommitMessageParserException $ex) {
         if ($this->getArgument('verbatim')) {
           // In verbatim mode, just bail when we hit an error. The user can
           // rerun without --verbatim if they want to fix it manually. Most
           // users will probably `git commit --amend` instead.
           throw $ex;
         }
         $fields[$hash] = $message->getFields();
 
         $frev = substr($hash, 0, 12);
         $notes[] = pht(
           'NOTE: commit %s could not be completely parsed:',
           $frev);
         foreach ($ex->getParserErrors() as $error) {
           $notes[] = "  - {$error}";
         }
       }
     }
 
     // Merge commit message fields. We do this somewhat-intelligently so that
     // multiple "Reviewers" or "CC" fields will merge into the concatenation
     // of all values.
 
     // We have special parsing rules for 'title' because we can't merge
     // multiple titles, and one-line commit messages like "fix stuff" will
     // parse as titles. Instead, pick the first title we encounter. When we
     // encounter subsequent titles, treat them as part of the summary. Then
     // we merge all the summaries together below.
 
     $result = array();
 
     // Process fields in oldest-first order, so earlier commits get to set the
     // title of record and reviewers/ccs are listed in chronological order.
     $fields = array_reverse($fields);
 
     foreach ($fields as $hash => $dict) {
       $title = idx($dict, 'title');
       if (!strlen($title)) {
         continue;
       }
 
       if ($title === $placeholder_title) {
         continue;
       }
 
       if (!isset($result['title'])) {
         // We don't have a title yet, so use this one.
         $result['title'] = $title;
       } else {
         // We already have a title, so merge this new title into the summary.
         $summary = idx($dict, 'summary');
         if ($summary) {
           $summary = $title."\n\n".$summary;
         } else {
           $summary = $title;
         }
         $fields[$hash]['summary'] = $summary;
       }
     }
 
     // Now, merge all the other fields in a general sort of way.
 
     foreach ($fields as $hash => $dict) {
       foreach ($dict as $key => $value) {
         if ($key == 'title') {
           // This has been handled above, and either assigned directly or
           // merged into the summary.
           continue;
         }
 
         if (is_array($value)) {
           // For array values, merge the arrays, appending the new values.
           // Examples are "Reviewers" and "Cc", where this produces a list of
           // all users specified as reviewers.
           $cur = idx($result, $key, array());
           $new = array_merge($cur, $value);
           $result[$key] = $new;
           continue;
         } else {
           if (!strlen(trim($value))) {
             // Ignore empty fields.
             continue;
           }
 
           // For string values, append the new field to the old field with
           // a blank line separating them. Examples are "Test Plan" and
           // "Summary".
           $cur = idx($result, $key, '');
           if (strlen($cur)) {
             $new = $cur."\n\n".$value;
           } else {
             $new = $value;
           }
           $result[$key] = $new;
         }
       }
     }
 
     return array($result, $notes, $included);
   }
 
   private function getDefaultUpdateMessage() {
     if ($this->isRawDiffSource()) {
       return null;
     }
 
     $repository_api = $this->getRepositoryAPI();
     if ($repository_api instanceof ArcanistGitAPI) {
       return $this->getGitUpdateMessage();
     }
 
     if ($repository_api instanceof ArcanistMercurialAPI) {
       return $this->getMercurialUpdateMessage();
     }
 
     return null;
   }
 
   /**
    * Retrieve the git messages between HEAD and the last update.
    *
    * @task message
    */
   private function getGitUpdateMessage() {
     $repository_api = $this->getRepositoryAPI();
 
     $parser = $this->newDiffParser();
     $commit_messages = $repository_api->getGitCommitLog();
     $commit_messages = $parser->parseDiff($commit_messages);
 
     if (count($commit_messages) == 1) {
       // If there's only one message, assume this is an amend-based workflow and
       // that using it to prefill doesn't make sense.
       return null;
     }
 
     // We have more than one message, so figure out which ones are new. We
     // do this by pulling the current diff and comparing commit hashes in the
     // working copy with attached commit hashes. It's not super important that
     // we always get this 100% right, we're just trying to do something
     // reasonable.
 
     $hashes = $this->loadActiveDiffLocalCommitHashes();
     $hashes = array_fuse($hashes);
 
     $usable = array();
     foreach ($commit_messages as $message) {
       $text = $message->getMetadata('message');
 
       $parsed = ArcanistDifferentialCommitMessage::newFromRawCorpus($text);
       if ($parsed->getRevisionID()) {
         // If this is an amended commit message with a revision ID, it's
         // certainly not new. Stop marking commits as usable and break out.
         break;
       }
 
       if (isset($hashes[$message->getCommitHash()])) {
         // If this commit is currently part of the diff, stop using commit
         // messages, since anything older than this isn't new.
         break;
       }
 
       // Otherwise, this looks new, so it's a usable commit message.
       $usable[] = $text;
     }
 
     if (!$usable) {
       // No new commit messages, so we don't have anywhere to start from.
       return null;
     }
 
     return $this->formatUsableLogs($usable);
   }
 
   /**
    * Retrieve the hg messages between tip and the last update.
    *
    * @task message
    */
   private function getMercurialUpdateMessage() {
     $repository_api = $this->getRepositoryAPI();
 
     $messages = $repository_api->getCommitMessageLog();
 
     if (count($messages) == 1) {
       // If there's only one message, assume this is an amend-based workflow and
       // that using it to prefill doesn't make sense.
       return null;
     }
 
     $hashes = $this->loadActiveDiffLocalCommitHashes();
     $hashes = array_fuse($hashes);
 
     $usable = array();
     foreach ($messages as $rev => $message) {
       if (isset($hashes[$rev])) {
         // If this commit is currently part of the active diff on the revision,
         // stop using commit messages, since anything older than this isn't new.
         break;
       }
 
       // Otherwise, this looks new, so it's a usable commit message.
       $usable[] = $message;
     }
 
     if (!$usable) {
       // No new commit messages, so we don't have anywhere to start from.
       return null;
     }
 
     return $this->formatUsableLogs($usable);
   }
 
 
   /**
    * Format log messages to prefill a diff update.
    *
    * @task message
    */
   private function formatUsableLogs(array $usable) {
     // Flip messages so they'll read chronologically (oldest-first) in the
     // template, e.g.:
     //
     //   - Added foobar.
     //   - Fixed foobar bug.
     //   - Documented foobar.
 
     $usable = array_reverse($usable);
     $default = array();
     foreach ($usable as $message) {
       // Pick the first line out of each message.
       $text = trim($message);
       $text = head(explode("\n", $text));
       $default[] = '  - '.$text."\n";
     }
 
     return implode('', $default);
   }
 
   private function loadActiveDiffLocalCommitHashes() {
     // The older "differential.querydiffs" method includes the full diff text,
     // which can be very slow for large diffs. If we can, try to use
     // "differential.diff.search" instead.
 
     // We expect this to fail if the Phabricator version on the server is
     // older than April 2018 (D19386), which introduced the "commits"
     // attachment for "differential.revision.search".
 
     // TODO: This can be optimized if we're able to learn the "revisionPHID"
     // before we get here. See PHI1104.
 
     try {
       $revisions_raw = $this->getConduit()->callMethodSynchronous(
         'differential.revision.search',
         array(
           'constraints' => array(
             'ids' => array(
               $this->revisionID,
             ),
           ),
         ));
 
       $revisions = $revisions_raw['data'];
       $revision = head($revisions);
       if ($revision) {
         $revision_phid = $revision['phid'];
 
         $diffs_raw = $this->getConduit()->callMethodSynchronous(
           'differential.diff.search',
           array(
             'constraints' => array(
               'revisionPHIDs' => array(
                 $revision_phid,
               ),
             ),
             'attachments' => array(
               'commits' => true,
             ),
             'limit' => 1,
           ));
 
         $diffs = $diffs_raw['data'];
         $diff = head($diffs);
 
         if ($diff) {
           $commits = idxv($diff, array('attachments', 'commits', 'commits'));
           if ($commits !== null) {
             $hashes = ipull($commits, 'identifier');
             return array_values($hashes);
           }
         }
       }
     } catch (Exception $ex) {
       // If any of this fails, fall back to the older method below.
     }
 
     $current_diff = $this->getConduit()->callMethodSynchronous(
       'differential.querydiffs',
       array(
         'revisionIDs' => array($this->revisionID),
       ));
     $current_diff = head($current_diff);
 
     $properties = idx($current_diff, 'properties', array());
     $local = idx($properties, 'local:commits', array());
     $hashes = ipull($local, 'commit');
 
     return array_values($hashes);
   }
 
 
 /* -(  Diff Specification  )------------------------------------------------- */
 
 
   /**
    * @task diffspec
    */
   private function getLintStatus($lint_result) {
     $map = array(
       ArcanistLintWorkflow::RESULT_OKAY       => 'okay',
       ArcanistLintWorkflow::RESULT_ERRORS     => 'fail',
       ArcanistLintWorkflow::RESULT_WARNINGS   => 'warn',
       ArcanistLintWorkflow::RESULT_SKIP       => 'skip',
     );
     return idx($map, $lint_result, 'none');
   }
 
 
   /**
    * @task diffspec
    */
   private function getUnitStatus($unit_result) {
     $map = array(
       ArcanistUnitWorkflow::RESULT_OKAY       => 'okay',
       ArcanistUnitWorkflow::RESULT_FAIL       => 'fail',
       ArcanistUnitWorkflow::RESULT_UNSOUND    => 'warn',
       ArcanistUnitWorkflow::RESULT_SKIP       => 'skip',
     );
     return idx($map, $unit_result, 'none');
   }
 
 
   /**
    * @task diffspec
    */
   private function buildDiffSpecification() {
 
     $base_revision  = null;
     $base_path      = null;
     $vcs            = null;
     $repo_uuid      = null;
     $parent         = null;
     $source_path    = null;
     $branch         = null;
     $bookmark       = null;
 
     if (!$this->isRawDiffSource()) {
       $repository_api = $this->getRepositoryAPI();
 
       $base_revision  = $repository_api->getSourceControlBaseRevision();
       $base_path      = $repository_api->getSourceControlPath();
       $vcs            = $repository_api->getSourceControlSystemName();
       $source_path    = $repository_api->getPath();
       $branch         = $repository_api->getBranchName();
       $repo_uuid      = $repository_api->getRepositoryUUID();
 
       if ($repository_api instanceof ArcanistGitAPI) {
         $info = $this->getGitParentLogInfo();
         if ($info['parent']) {
           $parent = $info['parent'];
         }
         if ($info['base_revision']) {
           $base_revision = $info['base_revision'];
         }
         if ($info['base_path']) {
           $base_path = $info['base_path'];
         }
         if ($info['uuid']) {
           $repo_uuid = $info['uuid'];
         }
       } else if ($repository_api instanceof ArcanistMercurialAPI) {
 
         $bookmark = $repository_api->getActiveBookmark();
         $svn_info = $repository_api->getSubversionInfo();
         $repo_uuid = idx($svn_info, 'uuid');
         $base_path = idx($svn_info, 'base_path', $base_path);
         $base_revision = idx($svn_info, 'base_revision', $base_revision);
 
         // TODO: provide parent info
 
       }
     }
 
     $data = array(
       'sourceMachine'             => php_uname('n'),
       'sourcePath'                => $source_path,
       'branch'                    => $branch,
       'bookmark'                  => $bookmark,
       'sourceControlSystem'       => $vcs,
       'sourceControlPath'         => $base_path,
       'sourceControlBaseRevision' => $base_revision,
       'creationMethod'            => 'arc',
     );
 
     if (!$this->isRawDiffSource()) {
       $repository_phid = $this->getRepositoryPHID();
       if ($repository_phid) {
         $data['repositoryPHID'] = $repository_phid;
       }
     }
 
     return $data;
   }
 
 
 /* -(  Diff Properties  )---------------------------------------------------- */
 
 
   /**
    * Update lint information for the diff.
    *
    * @return void
    *
    * @task diffprop
    */
   private function updateLintDiffProperty() {
     if (!$this->hitAutotargets) {
       if ($this->unresolvedLint) {
         $this->updateDiffProperty(
           'arc:lint',
           json_encode($this->unresolvedLint));
       }
     }
   }
 
 
   /**
    * Update unit test information for the diff.
    *
    * @return void
    *
    * @task diffprop
    */
   private function updateUnitDiffProperty() {
     if (!$this->hitAutotargets) {
       if ($this->testResults) {
         $this->updateDiffProperty('arc:unit', json_encode($this->testResults));
       }
     }
   }
 
 
   /**
    * Update local commit information for the diff.
    *
    * @task diffprop
    */
   private function updateLocalDiffProperty() {
     if ($this->isRawDiffSource()) {
       return;
     }
 
     $local_info = $this->getRepositoryAPI()->getLocalCommitInformation();
     if (!$local_info) {
       return;
     }
 
     $this->updateDiffProperty('local:commits', json_encode($local_info));
   }
 
   private function updateOntoDiffProperty() {
     $onto = $this->getDiffOntoTargets();
 
     if (!$onto) {
       return;
     }
 
     $this->updateDiffProperty('arc:onto', json_encode($onto));
   }
 
   private function getDiffOntoTargets() {
     if ($this->isRawDiffSource()) {
       return null;
     }
 
     $api = $this->getRepositoryAPI();
 
     if (!($api instanceof ArcanistGitAPI)) {
       return null;
     }
 
     // If we track an upstream branch either directly or indirectly, use that.
     $branch = $api->getBranchName();
     if (strlen($branch)) {
       $upstream_path = $api->getPathToUpstream($branch);
       $remote_branch = $upstream_path->getRemoteBranchName();
       if (strlen($remote_branch)) {
         return array(
           array(
             'type' => 'branch',
             'name' => $remote_branch,
             'kind' => 'upstream',
           ),
         );
       }
     }
 
     // If "arc.land.onto.default" is configured, use that.
     $config_key = 'arc.land.onto.default';
     $onto = $this->getConfigFromAnySource($config_key);
     if (strlen($onto)) {
       return array(
         array(
           'type' => 'branch',
           'name' => $onto,
           'kind' => 'arc.land.onto.default',
         ),
       );
     }
 
     return null;
   }
 
   /**
    * Update an arbitrary diff property.
    *
    * @param string Diff property name.
    * @param string Diff property value.
    * @return void
    *
    * @task diffprop
    */
   private function updateDiffProperty($name, $data) {
     $this->diffPropertyFutures[] = $this->getConduit()->callMethod(
       'differential.setdiffproperty',
       array(
         'diff_id' => $this->getDiffID(),
         'name'    => $name,
         'data'    => $data,
       ));
   }
 
   /**
    * Wait for finishing all diff property updates.
    *
    * @return void
    *
    * @task diffprop
    */
   private function resolveDiffPropertyUpdates() {
     id(new FutureIterator($this->diffPropertyFutures))
       ->resolveAll();
     $this->diffPropertyFutures = array();
   }
 
   private function dispatchWillCreateRevisionEvent(array $fields) {
     $event = $this->dispatchEvent(
       ArcanistEventType::TYPE_REVISION_WILLCREATEREVISION,
       array(
         'specification' => $fields,
       ));
 
     return $event->getValue('specification');
   }
 
   private function dispatchWillBuildEvent(array $fields) {
     $event = $this->dispatchEvent(
       ArcanistEventType::TYPE_DIFF_WILLBUILDMESSAGE,
       array(
         'fields' => $fields,
       ));
 
     return $event->getValue('fields');
   }
 
   private function checkRevisionOwnership(array $revision) {
     if ($revision['authorPHID'] == $this->getUserPHID()) {
       return;
     }
 
     $id = $revision['id'];
     $title = $revision['title'];
 
     $prompt = pht(
       "You don't own revision %s: \"%s\". Normally, you should ".
       "only update revisions you own. You can \"Commandeer\" this revision ".
       "from the web interface if you want to become the owner.\n\n".
       "Update this revision anyway?",
       "D{$id}",
       $title);
 
     $ok = phutil_console_confirm($prompt, $default_no = true);
     if (!$ok) {
       throw new ArcanistUsageException(
         pht('Aborted update of revision: You are not the owner.'));
     }
   }
 
 
 /* -(  File Uploads  )------------------------------------------------------- */
 
 
   private function uploadFilesForChanges(array $changes) {
     assert_instances_of($changes, 'ArcanistDiffChange');
 
     // Collect all the files we need to upload.
 
     $need_upload = array();
     foreach ($changes as $key => $change) {
       if ($change->getFileType() != ArcanistDiffChangeType::FILE_BINARY) {
         continue;
       }
 
       if ($this->getArgument('skip-binaries')) {
         continue;
       }
 
       $name = basename($change->getCurrentPath());
 
       $need_upload[] = array(
         'type' => 'old',
         'name' => $name,
         'data' => $change->getOriginalFileData(),
         'change' => $change,
       );
 
       $need_upload[] = array(
         'type' => 'new',
         'name' => $name,
         'data' => $change->getCurrentFileData(),
         'change' => $change,
       );
     }
 
     if (!$need_upload) {
       return;
     }
 
     // Determine mime types and file sizes. Update changes from "binary" to
     // "image" if the file is an image. Set image metadata.
 
     $type_image = ArcanistDiffChangeType::FILE_IMAGE;
     foreach ($need_upload as $key => $spec) {
       $change = $need_upload[$key]['change'];
 
       if ($spec['data'] === null) {
         // This covers the case where a file was added or removed; we don't
         // need to upload the other half of it (e.g., the old file data for
         // a file which was just added). This is distinct from an empty
         // file, which we do upload.
         unset($need_upload[$key]);
         continue;
       }
 
       $type = $spec['type'];
       $size = strlen($spec['data']);
 
       $change->setMetadata("{$type}:file:size", $size);
 
       $mime = $this->getFileMimeType($spec['data']);
       if (preg_match('@^image/@', $mime)) {
         $change->setFileType($type_image);
       }
 
       $change->setMetadata("{$type}:file:mime-type", $mime);
     }
 
     $uploader = id(new ArcanistFileUploader())
       ->setConduitEngine($this->getConduitEngine());
 
     foreach ($need_upload as $key => $spec) {
       $ref = id(new ArcanistFileDataRef())
         ->setName($spec['name'])
         ->setData($spec['data']);
 
       $uploader->addFile($ref, $key);
     }
 
     $files = $uploader->uploadFiles();
 
     $errors = false;
     foreach ($files as $key => $file) {
       if ($file->getErrors()) {
         unset($files[$key]);
         $errors = true;
         echo pht(
           'Failed to upload binary "%s".',
           $file->getName());
       }
     }
 
     if ($errors) {
       $prompt = pht('Continue?');
       $ok = phutil_console_confirm($prompt, $default_no = false);
       if (!$ok) {
         throw new ArcanistUsageException(
           pht(
             'Aborted due to file upload failure. You can use %s '.
             'to skip binary uploads.',
             '--skip-binaries'));
       }
     }
 
     foreach ($files as $key => $file) {
       $spec = $need_upload[$key];
       $phid = $file->getPHID();
 
       $change = $spec['change'];
       $type = $spec['type'];
       $change->setMetadata("{$type}:binary-phid", $phid);
 
       echo pht('Uploaded binary data for "%s".', $file->getName())."\n";
     }
 
     echo pht('Upload complete.')."\n";
   }
 
   private function getFileMimeType($data) {
     $tmp = new TempFile();
     Filesystem::writeFile($tmp, $data);
     return Filesystem::getMimeType($tmp);
   }
 
   private function shouldOpenCreatedObjectsInBrowser() {
     return $this->getArgument('browse');
   }
 
   private function submitChangesToStagingArea($id) {
     $result = $this->pushChangesToStagingArea($id);
 
     // We'll either get a failure constant on error, or a list of pushed
     // refs on success.
     $ok = is_array($result);
 
     if ($ok) {
       $staging = array(
         'status' => self::STAGING_PUSHED,
         'refs' => $result,
       );
     } else {
       $staging = array(
         'status' => $result,
         'refs' => array(),
       );
     }
 
     $this->updateDiffProperty(
       'arc.staging',
       phutil_json_encode($staging));
   }
 
   private function pushChangesToStagingArea($id) {
     if ($this->getArgument('skip-staging')) {
       $this->writeInfo(
         pht('SKIP STAGING'),
         pht('Flag --skip-staging was specified.'));
       return self::STAGING_USER_SKIP;
     }
 
     if ($this->isRawDiffSource()) {
       $this->writeInfo(
         pht('SKIP STAGING'),
         pht('Raw changes can not be pushed to a staging area.'));
       return self::STAGING_DIFF_RAW;
     }
 
     if (!$this->getRepositoryPHID()) {
       $this->writeInfo(
         pht('SKIP STAGING'),
         pht('Unable to determine repository for this change.'));
       return self::STAGING_REPOSITORY_UNKNOWN;
     }
 
     $staging = $this->getRepositoryStagingConfiguration();
     if ($staging === null) {
       $this->writeInfo(
         pht('SKIP STAGING'),
         pht('The server does not support staging areas.'));
       return self::STAGING_REPOSITORY_UNAVAILABLE;
     }
 
     $supported = idx($staging, 'supported');
     if (!$supported) {
       $this->writeInfo(
         pht('SKIP STAGING'),
         pht('Phabricator does not support staging areas for this repository.'));
       return self::STAGING_REPOSITORY_UNSUPPORTED;
     }
 
     $staging_uri = idx($staging, 'uri');
     if (!$staging_uri) {
       $this->writeInfo(
         pht('SKIP STAGING'),
         pht('No staging area is configured for this repository.'));
       return self::STAGING_REPOSITORY_UNCONFIGURED;
     }
 
     $api = $this->getRepositoryAPI();
     if (!($api instanceof ArcanistGitAPI)) {
       $this->writeInfo(
         pht('SKIP STAGING'),
         pht('This client version does not support staging this repository.'));
       return self::STAGING_CLIENT_UNSUPPORTED;
     }
 
     $commit = $api->getHeadCommit();
     $prefix = idx($staging, 'prefix', 'phabricator');
 
     $base_tag = "refs/tags/{$prefix}/base/{$id}";
     $diff_tag = "refs/tags/{$prefix}/diff/{$id}";
 
     $this->writeOkay(
       pht('PUSH STAGING'),
       pht('Pushing changes to staging area...'));
 
     $push_flags = array();
     if (version_compare($api->getGitVersion(), '1.8.2', '>=')) {
       $push_flags[] = '--no-verify';
     }
 
     $refs = array();
 
     $remote = array(
       'uri' => $staging_uri,
     );
 
     $is_lfs = $api->isGitLFSWorkingCopy();
 
     // If the base commit is a real commit, we're going to push it. We don't
     // use this, but pushing it to a ref reduces the amount of redundant work
     // that Git does on later pushes by helping it figure out that the remote
     // already has most of the history. See T10509.
 
     // In the future, we could avoid this push if the staging area is the same
     // as the main repository, or if the staging area is a virtual repository.
     // In these cases, the staging area should automatically have up-to-date
     // refs.
     $base_commit = $api->getSourceControlBaseRevision();
     if ($base_commit !== ArcanistGitAPI::GIT_MAGIC_ROOT_COMMIT) {
       $refs[] = array(
         'ref' => $base_tag,
         'type' => 'base',
         'commit' => $base_commit,
         'remote' => $remote,
       );
     }
 
     // We're always going to push the change itself.
     $refs[] = array(
       'ref' => $diff_tag,
       'type' => 'diff',
       'commit' => $is_lfs ? $base_commit : $commit,
       'remote' => $remote,
     );
 
     $ref_list = array();
     foreach ($refs as $ref) {
       $ref_list[] = $ref['commit'].':'.$ref['ref'];
     }
 
     $err = phutil_passthru(
       'git push %Ls -- %s %Ls',
       $push_flags,
       $staging_uri,
       $ref_list);
 
     if ($err) {
       $this->writeWarn(
         pht('STAGING FAILED'),
         pht('Unable to push changes to the staging area.'));
 
       throw new ArcanistUsageException(
         pht(
           'Failed to push changes to staging area. Correct the issue, or '.
           'use --skip-staging to skip this step.'));
     }
 
     if ($is_lfs) {
       $ref = '+'.$commit.':'.$diff_tag;
       $err = phutil_passthru(
         'git push -- %s %s',
         $staging_uri,
         $ref);
+
+      if ($err) {
+        $this->writeWarn(
+          pht('STAGING FAILED'),
+          pht('Unable to push lfs changes to the staging area.'));
+
+        throw new ArcanistUsageException(
+          pht(
+            'Failed to push lfs changes to staging area. Correct the issue, '.
+            'or use --skip-staging to skip this step.'));
+      }
     }
 
     return $refs;
   }
 
 
   /**
    * Try to upload lint and unit test results into modern Harbormaster build
    * targets.
    *
    * @return bool True if everything was uploaded to build targets.
    */
   private function updateAutotargets($diff_phid, $unit_result) {
     $lint_key = 'arcanist.lint';
     $unit_key = 'arcanist.unit';
 
     try {
       $result = $this->getConduit()->callMethodSynchronous(
         'harbormaster.queryautotargets',
         array(
           'objectPHID' => $diff_phid,
           'targetKeys' => array(
             $lint_key,
             $unit_key,
           ),
         ));
       $targets = idx($result, 'targetMap', array());
     } catch (Exception $ex) {
       return false;
     }
 
     $futures = array();
 
     $lint_target = idx($targets, $lint_key);
     if ($lint_target) {
       $lint = nonempty($this->unresolvedLint, array());
       foreach ($lint as $key => $message) {
         $lint[$key] = $this->getModernLintDictionary($message);
       }
 
       // Consider this target to have failed if there are any unresolved
       // errors or warnings.
       $type = 'pass';
       foreach ($lint as $message) {
         switch (idx($message, 'severity')) {
           case ArcanistLintSeverity::SEVERITY_WARNING:
           case ArcanistLintSeverity::SEVERITY_ERROR:
             $type = 'fail';
             break;
         }
       }
 
       $futures[] = $this->getConduit()->callMethod(
         'harbormaster.sendmessage',
         array(
           'buildTargetPHID' => $lint_target,
           'lint' => array_values($lint),
           'type' => $type,
         ));
     }
 
     $unit_target = idx($targets, $unit_key);
     if ($unit_target) {
       $unit = nonempty($this->testResults, array());
       foreach ($unit as $key => $message) {
         $unit[$key] = $this->getModernUnitDictionary($message);
       }
 
       $type = ArcanistUnitWorkflow::getHarbormasterTypeFromResult($unit_result);
 
       $futures[] = $this->getConduit()->callMethod(
         'harbormaster.sendmessage',
         array(
           'buildTargetPHID' => $unit_target,
           'unit' => array_values($unit),
           'type' => $type,
         ));
     }
 
     try {
       foreach (new FutureIterator($futures) as $future) {
         $future->resolve();
       }
       return true;
     } catch (Exception $ex) {
       // TODO: Eventually, we should expect these to succeed if we get this
       // far, but just log errors for now.
       phlog($ex);
       return false;
     }
   }
 
   private function getDependsOnRevisionRef() {
     // TODO: Restore this behavior after updating for toolsets. Loading the
     // required hardpoints currently depends on a "WorkingCopy" existing.
     return null;
 
     $api = $this->getRepositoryAPI();
     $base_ref = $api->getBaseCommitRef();
 
     $state_ref = id(new ArcanistWorkingCopyStateRef())
       ->setCommitRef($base_ref);
 
     $this->loadHardpoints(
       $state_ref,
       ArcanistWorkingCopyStateRef::HARDPOINT_REVISIONREFS);
 
     $revision_refs = $state_ref->getRevisionRefs();
     $viewer_phid = $this->getUserPHID();
 
     foreach ($revision_refs as $key => $revision_ref) {
       // Don't automatically depend on closed revisions.
       if ($revision_ref->isClosed()) {
         unset($revision_refs[$key]);
         continue;
       }
 
       // Don't automatically depend on revisions authored by other users.
       if ($revision_ref->getAuthorPHID() != $viewer_phid) {
         unset($revision_refs[$key]);
         continue;
       }
     }
 
     if (!$revision_refs) {
       return null;
     }
 
     if (count($revision_refs) > 1) {
       return null;
     }
 
     return head($revision_refs);
   }
 
 }
diff --git a/support/init/init-script.php b/support/init/init-script.php
index a8c800f7..2b742074 100644
--- a/support/init/init-script.php
+++ b/support/init/init-script.php
@@ -1,115 +1,121 @@
 <?php
 
 function __arcanist_init_script__() {
   // Adjust the runtime language configuration to be reasonable and inline with
   // expectations. We do this first, then load libraries.
 
   // There may be some kind of auto-prepend script configured which starts an
   // output buffer. Discard any such output buffers so messages can be sent to
   // stdout (if a user wants to capture output from a script, there are a large
   // number of ways they can accomplish it legitimately; historically, we ran
   // into this on only one install which had some bizarre configuration, but it
   // was difficult to diagnose because the symptom is "no messages of any
   // kind").
   while (ob_get_level() > 0) {
     ob_end_clean();
   }
 
   error_reporting(E_ALL | E_STRICT);
 
   $config_map = array(
     // Always display script errors. Without this, they may not appear, which is
     // unhelpful when users encounter a problem. On the web this is a security
     // concern because you don't want to expose errors to clients, but in a
     // script context we always want to show errors.
     'display_errors'              => true,
 
     // Send script error messages to the server's `error_log` setting.
     'log_errors'                  => true,
 
     // Set the error log to the default, so errors go to stderr. Without this
     // errors may end up in some log, and users may not know where the log is
     // or check it.
     'error_log'                   => null,
 
     // XDebug raises a fatal error if the call stack gets too deep, but the
     // default setting is 100, which we may exceed legitimately with module
     // includes (and in other cases, like recursive filesystem operations
     // applied to 100+ levels of directory nesting). Stop it from triggering:
     // we explicitly limit recursive algorithms which should be limited.
     //
     // After Feb 2014, XDebug interprets a value of 0 to mean "do not allow any
     // function calls". Previously, 0 effectively disabled this check. For
     // context, see T5027.
     'xdebug.max_nesting_level'    => PHP_INT_MAX,
 
     // Don't limit memory, doing so just generally just prevents us from
     // processing large inputs without many tangible benefits.
     'memory_limit'                => -1,
 
     // See T13296. On macOS under PHP 7.3.x, PCRE currently segfaults after
     // "fork()" if "pcre.jit" is enabled.
     'pcre.jit' => 0,
+
+    // See PHI1894. This option was introduced in PHP 7.4, and removes the
+    // "args" value from exception backtraces. We have some unit tests which
+    // inspect "args", and this option generally obscures useful debugging
+    // information without any benefit in the context of Phabricator.
+    'zend.exception_ignore_args' => 0,
   );
 
   foreach ($config_map as $config_key => $config_value) {
     ini_set($config_key, $config_value);
   }
 
   $php_version = phpversion();
   $min_version = '5.5.0';
   if (version_compare($php_version, $min_version, '<')) {
     echo sprintf(
       'UPGRADE PHP: '.
       'The installed version of PHP ("%s") is too old to run Arcanist. '.
       'Update PHP to at least the minimum required version ("%s").',
       $php_version,
       $min_version);
     echo "\n";
 
     exit(1);
   }
 
   if (!ini_get('date.timezone')) {
     // If the timezone isn't set, PHP issues a warning whenever you try to parse
     // a date (like those from Git or Mercurial logs), even if the date contains
     // timezone information (like "PST" or "-0700") which makes the
     // environmental timezone setting is completely irrelevant. We never rely on
     // the system timezone setting in any capacity, so prevent PHP from flipping
     // out by setting it to a safe default (UTC) if it isn't set to some other
     // value.
     date_default_timezone_set('UTC');
   }
 
   // Adjust `include_path`.
   ini_set('include_path', implode(PATH_SEPARATOR, array(
     dirname(dirname(__FILE__)).'/externals/includes',
     ini_get('include_path'),
   )));
 
   // Disable the insanely dangerous XML entity loader by default.
   if (function_exists('libxml_disable_entity_loader')) {
     libxml_disable_entity_loader(true);
   }
 
   $root = dirname(dirname(dirname(__FILE__)));
   require_once $root.'/src/init/init-library.php';
 
   PhutilErrorHandler::initialize();
 
   PhutilErrorHandler::initialize();
 
   // If "variables_order" excludes "E", silently repair it so that $_ENV has
   // the values we expect.
   PhutilExecutionEnvironment::repairMissingVariablesOrder();
 
   $router = PhutilSignalRouter::initialize();
 
   $handler = new PhutilBacktraceSignalHandler();
   $router->installHandler('phutil.backtrace', $handler);
 
   $handler = new PhutilConsoleMetricsSignalHandler();
   $router->installHandler('phutil.winch', $handler);
 }
 
 __arcanist_init_script__();