diff --git a/src/unit/parser/ArcanistPhpunitTestResultParser.php b/src/unit/parser/ArcanistPhpunitTestResultParser.php
index 46e9c131..5ccff970 100644
--- a/src/unit/parser/ArcanistPhpunitTestResultParser.php
+++ b/src/unit/parser/ArcanistPhpunitTestResultParser.php
@@ -1,189 +1,188 @@
 <?php
 
 /**
  * PHPUnit Result Parsing utility
  *
  * For an example on how to integrate with your test engine, see
  * @{class:PhpunitTestEngine}.
  */
 final class ArcanistPhpunitTestResultParser extends ArcanistTestResultParser {
 
   /**
    * Parse test results from phpunit json report
    *
    * @param string $path Path to test
    * @param string $test_results String containing phpunit json report
    *
    * @return array
    */
   public function parseTestResults($path, $test_results) {
     if (!$test_results) {
       $result = id(new ArcanistUnitTestResult())
         ->setName($path)
         ->setUserData($this->stderr)
         ->setResult(ArcanistUnitTestResult::RESULT_BROKEN);
       return array($result);
     }
 
     $report = $this->getJsonReport($test_results);
 
     // coverage is for all testcases in the executed $path
     $coverage = array();
     if ($this->enableCoverage !== false) {
       $coverage = $this->readCoverage();
     }
 
     $last_test_finished = true;
 
     $results = array();
     foreach ($report as $event) {
       switch (idx($event, 'event')) {
       case 'test':
         break;
       case 'testStart':
         $last_test_finished = false;
         // fall through
         default:
           continue 2; // switch + loop
       }
 
       $status = ArcanistUnitTestResult::RESULT_PASS;
       $user_data = '';
 
       if ('fail' == idx($event, 'status')) {
         $status = ArcanistUnitTestResult::RESULT_FAIL;
         $user_data  .= idx($event, 'message')."\n";
         foreach (idx($event, 'trace') as $trace) {
           $user_data .= sprintf(
             "\n%s:%s",
             idx($trace, 'file'),
             idx($trace, 'line'));
         }
       } else if ('error' == idx($event, 'status')) {
         if (strpos(idx($event, 'message'), 'Skipped Test') !== false) {
           $status = ArcanistUnitTestResult::RESULT_SKIP;
           $user_data .= idx($event, 'message');
         } else if (strpos(
             idx($event, 'message'),
             'Incomplete Test') !== false) {
           $status = ArcanistUnitTestResult::RESULT_SKIP;
           $user_data .= idx($event, 'message');
         } else {
           $status = ArcanistUnitTestResult::RESULT_BROKEN;
           $user_data  .= idx($event, 'message');
           foreach (idx($event, 'trace') as $trace) {
             $user_data .= sprintf(
               "\n%s:%s",
               idx($trace, 'file'),
               idx($trace, 'line'));
           }
         }
       }
 
       $name = preg_replace('/ \(.*\)/s', '', idx($event, 'test'));
 
       $result = new ArcanistUnitTestResult();
       $result->setName($name);
       $result->setResult($status);
       $result->setDuration(idx($event, 'time'));
       $result->setCoverage($coverage);
       $result->setUserData($user_data);
 
       $results[] = $result;
       $last_test_finished = true;
     }
 
     if (!$last_test_finished) {
       $results[] = id(new ArcanistUnitTestResult())
         ->setName(idx($event, 'test')) // use last event
         ->setUserData($this->stderr)
         ->setResult(ArcanistUnitTestResult::RESULT_BROKEN);
     }
     return $results;
   }
 
   /**
    * Read the coverage from phpunit generated clover report
    *
    * @return array
    */
   private function readCoverage() {
     $test_results = Filesystem::readFile($this->coverageFile);
     if (empty($test_results)) {
       return array();
     }
 
     $coverage_dom = new DOMDocument();
     $coverage_dom->loadXML($test_results);
 
     $reports = array();
     $files = $coverage_dom->getElementsByTagName('file');
 
     foreach ($files as $file) {
       $class_path = $file->getAttribute('name');
       if (empty($this->affectedTests[$class_path])) {
         continue;
       }
       $test_path = $this->affectedTests[$file->getAttribute('name')];
       // get total line count in file
       $line_count = count(file($class_path));
 
       $coverage = '';
+      $any_line_covered = false;
       $start_line = 1;
       $lines = $file->getElementsByTagName('line');
-      for ($ii = 0; $ii < $lines->length; $ii++) {
-        $line = $lines->item($ii);
-        for (; $start_line < $line->getAttribute('num'); $start_line++) {
-          $coverage .= 'N';
-        }
 
+      $coverage = str_repeat('N', $line_count);
+      foreach ($lines as $line) {
         if ($line->getAttribute('type') != 'stmt') {
-          $coverage .= 'N';
+          continue;
+        }
+        if ((int)$line->getAttribute('count') > 0) {
+          $is_covered = 'C';
+          $any_line_covered = true;
         } else {
-          if ((int)$line->getAttribute('count') == 0) {
-            $coverage .= 'U';
-          } else if ((int)$line->getAttribute('count') > 0) {
-            $coverage .= 'C';
-          }
+          $is_covered = 'U';
         }
-
-        $start_line++;
+        $line_no = (int)$line->getAttribute('num');
+        $coverage[$line_no - 1] = $is_covered;
       }
 
-      for (; $start_line <= $line_count; $start_line++) {
-        $coverage .= 'N';
+      // Sometimes the Clover coverage gives false positives on uncovered lines
+      // when the file wasn't actually part of the test. This filters out files
+      // with no coverage which helps give more accurate overall results.
+      if ($any_line_covered) {
+        $len = strlen($this->projectRoot.DIRECTORY_SEPARATOR);
+        $class_path = substr($class_path, $len);
+        $reports[$class_path] = $coverage;
       }
-
-      $len = strlen($this->projectRoot.DIRECTORY_SEPARATOR);
-      $class_path = substr($class_path, $len);
-      $reports[$class_path] = $coverage;
     }
 
     return $reports;
   }
 
   /**
    * We need this non-sense to make json generated by phpunit
    * valid.
    *
    * @param string $json String containing JSON report
    * @return array JSON decoded array
    */
   private function getJsonReport($json) {
 
     if (empty($json)) {
       throw new Exception(
         pht(
           'JSON report file is empty, it probably means that phpunit '.
           'failed to run tests. Try running %s with %s option and then run '.
           'generated phpunit command yourself, you might get the answer.',
           'arc unit',
           '--trace'));
     }
 
     $json = preg_replace('/}{\s*"/', '},{"', $json);
     $json = '['.$json.']';
     return phutil_json_decode($json);
   }
 
 }