PHP Diff::cleanupSemantic方法代码示例

 public function testCleanupSemantic()
 {
     // Cleanup semantically trivial equalities.
     // Null case.
     $this->d->setChanges(array());
     $this->d->cleanupSemantic();
     $this->assertEquals(array(), $this->d->getChanges());
     // No elimination #1.
     $this->d->setChanges(array(array(Diff::DELETE, "ab"), array(Diff::INSERT, "cd"), array(Diff::EQUAL, "12"), array(Diff::DELETE, "e")));
     $this->d->cleanupSemantic();
     $this->assertEquals(array(array(Diff::DELETE, "ab"), array(Diff::INSERT, "cd"), array(Diff::EQUAL, "12"), array(Diff::DELETE, "e")), $this->d->getChanges());
     // No elimination #2.
     $this->d->setChanges(array(array(Diff::DELETE, "abc"), array(Diff::INSERT, "ABC"), array(Diff::EQUAL, "1234"), array(Diff::DELETE, "wxyz")));
     $this->d->cleanupSemantic();
     $this->assertEquals(array(array(Diff::DELETE, "abc"), array(Diff::INSERT, "ABC"), array(Diff::EQUAL, "1234"), array(Diff::DELETE, "wxyz")), $this->d->getChanges());
     // Simple elimination.
     $this->d->setChanges(array(array(Diff::DELETE, "a"), array(Diff::EQUAL, "b"), array(Diff::DELETE, "c")));
     $this->d->cleanupSemantic();
     $this->assertEquals(array(array(Diff::DELETE, "abc"), array(Diff::INSERT, "b")), $this->d->getChanges());
     // Backpass elimination.
     $this->d->setChanges(array(array(Diff::DELETE, "ab"), array(Diff::EQUAL, "cd"), array(Diff::DELETE, "e"), array(Diff::EQUAL, "f"), array(Diff::INSERT, "g")));
     $this->d->cleanupSemantic();
     $this->assertEquals(array(array(Diff::DELETE, "abcdef"), array(Diff::INSERT, "cdfg")), $this->d->getChanges());
     // Multiple eliminations.
     $this->d->setChanges(array(array(Diff::INSERT, "1"), array(Diff::EQUAL, "A"), array(Diff::DELETE, "B"), array(Diff::INSERT, "2"), array(Diff::EQUAL, "_"), array(Diff::INSERT, "1"), array(Diff::EQUAL, "A"), array(Diff::DELETE, "B"), array(Diff::INSERT, "2")));
     $this->d->cleanupSemantic();
     $this->assertEquals(array(array(Diff::DELETE, "AB_AB"), array(Diff::INSERT, "1A2_1A2")), $this->d->getChanges());
     // Word boundaries.
     $this->d->setChanges(array(array(Diff::EQUAL, "The c"), array(Diff::DELETE, "ow and the c"), array(Diff::EQUAL, "at.")));
     $this->d->cleanupSemantic();
     $this->assertEquals(array(array(Diff::EQUAL, "The "), array(Diff::DELETE, "cow and the "), array(Diff::EQUAL, "cat.")), $this->d->getChanges());
     // No overlap elimination.
     $this->d->setChanges(array(array(Diff::DELETE, "abcxx"), array(Diff::INSERT, "xxdef")));
     $this->d->cleanupSemantic();
     $this->assertEquals(array(array(Diff::DELETE, "abcxx"), array(Diff::INSERT, "xxdef")), $this->d->getChanges());
     // Overlap elimination.
     $this->d->setChanges(array(array(Diff::DELETE, "abcxxx"), array(Diff::INSERT, "xxxdef")));
     $this->d->cleanupSemantic();
     $this->assertEquals(array(array(Diff::DELETE, "abc"), array(Diff::EQUAL, "xxx"), array(Diff::INSERT, "def")), $this->d->getChanges());
     // Reverse overlap elimination.
     $this->d->setChanges(array(array(Diff::DELETE, "xxxabc"), array(Diff::INSERT, "defxxx")));
     $this->d->cleanupSemantic();
     $this->assertEquals(array(array(Diff::INSERT, "def"), array(Diff::EQUAL, "xxx"), array(Diff::DELETE, "abc")), $this->d->getChanges());
     // Two overlap eliminations.
     $this->d->setChanges(array(array(Diff::DELETE, "abcd1212"), array(Diff::INSERT, "1212efghi"), array(Diff::EQUAL, "----"), array(Diff::DELETE, "A3"), array(Diff::INSERT, "3BC")));
     $this->d->cleanupSemantic();
     $this->assertEquals(array(array(Diff::DELETE, "abcd"), array(Diff::EQUAL, "1212"), array(Diff::INSERT, "efghi"), array(Diff::EQUAL, "----"), array(Diff::DELETE, "A"), array(Diff::EQUAL, "3"), array(Diff::INSERT, "BC")), $this->d->getChanges());
 }

 /**
  * Do a quick line-level diff on both strings, then rediff the parts for greater accuracy.
  * This speedup can produce non-minimal diffs.
  *
  * @param string $text1    Old string to be diffed.
  * @param string $text2    New string to be diffed.
  * @param int    $deadline Time when the diff should be complete by.
  *
  * @return array Array of changes.
  */
 protected function lineMode($text1, $text2, $deadline)
 {
     // Scan the text on a line-by-line basis first.
     list($text1, $text2, $lineArray) = $this->getToolkit()->linesToChars($text1, $text2);
     $diff = new Diff();
     $diff->main($text1, $text2, false, $deadline);
     $diffs = $diff->getChanges();
     // Convert the diff back to original text.
     $this->getToolkit()->charsToLines($diffs, $lineArray);
     $diff->setChanges($diffs);
     // Eliminate freak matches (e.g. blank lines)
     $diff->cleanupSemantic();
     $diffs = $diff->getChanges();
     // Rediff any replacement blocks, this time character-by-character.
     // Add a dummy entry at the end.
     array_push($diffs, array(self::EQUAL, ''));
     $pointer = 0;
     $countDelete = 0;
     $countInsert = 0;
     $textDelete = '';
     $textInsert = '';
     while ($pointer < count($diffs)) {
         switch ($diffs[$pointer][0]) {
             case self::DELETE:
                 $countDelete++;
                 $textDelete .= $diffs[$pointer][1];
                 break;
             case self::INSERT:
                 $countInsert++;
                 $textInsert .= $diffs[$pointer][1];
                 break;
             case self::EQUAL:
                 // Upon reaching an equality, check for prior redundancies.
                 if ($countDelete > 0 && $countInsert > 0) {
                     // Delete the offending records and add the merged ones.
                     $subDiff = new Diff();
                     $subDiff->main($textDelete, $textInsert, false, $deadline);
                     array_splice($diffs, $pointer - $countDelete - $countInsert, $countDelete + $countInsert, $subDiff->getChanges());
                     $pointer = $pointer - $countDelete - $countInsert + count($subDiff->getChanges());
                 }
                 $countDelete = 0;
                 $countInsert = 0;
                 $textDelete = '';
                 $textInsert = '';
                 break;
         }
         $pointer++;
     }
     // Remove the dummy entry at the end.
     array_pop($diffs);
     return $diffs;
 }

 /**
  * Reduce the number of edits by eliminating semantically trivial equalities.
  * Modifies $diffs.
  *
  * @param array $diffs Array of diff arrays.
  */
 public function diff_cleanupSemantic(&$diffs)
 {
     $this->diff->setChanges($diffs);
     $this->diff->cleanupSemantic();
     $diffs = $this->diff->getChanges();
 }