Index: src/workflow/ArcanistDiffWorkflow.php
===================================================================
--- src/workflow/ArcanistDiffWorkflow.php
+++ src/workflow/ArcanistDiffWorkflow.php
@@ -113,30 +113,12 @@
           'before updating.'),
       ),
       'raw' => array(
+        'param' => 'source',
         '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(
-          '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.'),
+          'Read diff from specified source, not from the working copy. '.
+          'Use "-" to read from stdin. '.
+          'This disables many features which depend on having access to '.
+          'the working copy.'),
       ),
       'create' => array(
         'help' => pht('Always create a new revision.'),
@@ -218,7 +200,6 @@
           'update'              => true,
           'only' => true,
           'raw'                 => true,
-          'raw-command'         => true,
           'message-file'        => true,
         ),
       ),
@@ -290,7 +271,7 @@
   }
 
   public function isRawDiffSource() {
-    return $this->getArgument('raw') || $this->getArgument('raw-command');
+    return $this->getArgument('raw');
   }
 
   public function run() {
@@ -754,13 +735,11 @@
     $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'));
+      $raw_path = $this->getArgument('raw');
+      if ($raw_path === '-') {
+        $raw_diff = $this->readStdin();
       } else {
-        throw new Exception(pht('Unknown raw diff source.'));
+        $raw_diff = Filesystem::readFile($raw_path);
       }
 
       $changes = $parser->parseDiff($raw_diff);
@@ -1054,8 +1033,7 @@
       return false;
     }
 
-    // Run this last: with --raw or --raw-command, we won't have a repository
-    // API.
+    // Run this last: with "--raw", we won't have a repository API.
     if ($this->isHistoryImmutable()) {
       return false;
     }
@@ -1431,7 +1409,7 @@
 
       $template = ArcanistCommentRemover::removeComments($new_template);
 
-      // With --raw-command, we may not have a repository API.
+      // With "--raw", 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