Add unified format

The code is there, so we may as well expose it.

Change-Id: Ic4cf5c0d4a5b46f0f0f25454815dcea1f69970eb

includes/diff/TextDiffer/BaseTextDiffer.php

@@ -2,6 +2,7 @@
 
 namespace MediaWiki\Diff\TextDiffer;
 
+use MediaWiki\Html\Html;
 use MessageLocalizer;
 use OutputPage;
 
@@ -40,8 +41,13 @@ abstract class BaseTextDiffer implements TextDiffer {
 	}
 
 	public function addRowWrapper( string $format, string $diffText ): string {
-		if ( $this->getFormatContext( $format ) === self::CONTEXT_PLAIN ) {
+		$context = $this->getFormatContext( $format );
+		if ( $context === self::CONTEXT_PLAIN ) {
 			return "<tr><td colspan=\"4\">$diffText</td></tr>";
+		} elseif ( $context === self::CONTEXT_PRE ) {
+			return '<tr><td colspan="4">' .
+				Html::element( 'pre', [], $diffText ) .
+				'</td></tr>';
 		} else {
 			return $diffText;
 		}

includes/diff/TextDiffer/PhpTextDiffer.php

@@ -5,6 +5,7 @@ namespace MediaWiki\Diff\TextDiffer;
 use Language;
 use Wikimedia\Diff\Diff;
 use Wikimedia\Diff\TableDiffFormatter;
+use Wikimedia\Diff\UnifiedDiffFormatter;
 
 /**
  * @since 1.41
@@ -22,11 +23,11 @@ class PhpTextDiffer extends BaseTextDiffer {
 	}
 
 	public function getFormats(): array {
-		return [ 'table' ];
+		return [ 'table', 'unified' ];
 	}
 
 	public function getFormatContext( string $format ) {
-		return $format === 'table' ? self::CONTEXT_ROW : self::CONTEXT_PLAIN;
+		return $format === 'table' ? self::CONTEXT_ROW : self::CONTEXT_PRE;
 	}
 
 	protected function doRenderBatch( string $oldText, string $newText, array $formats ): array {
@@ -40,8 +41,12 @@ class PhpTextDiffer extends BaseTextDiffer {
 		$diff = new Diff( $oldLines, $newLines );
 		$result = [];
 		foreach ( $formats as $format ) {
-			// @phan-suppress-next-line PhanNoopSwitchCases -- rectified in followup commit
 			switch ( $format ) {
+				case 'unified':
+					$formatter = new UnifiedDiffFormatter();
+					$diffText = $formatter->format( $diff );
+					break;
+
 				default: // 'table':
 					$formatter = new TableDiffFormatter();
 					$diffText = $formatter->format( $diff );

includes/diff/TextDiffer/TextDiffer.php

@@ -20,6 +20,11 @@ interface TextDiffer {
 	 */
 	public const CONTEXT_ROW = 'row';
 
+	/**
+	 * The return value is plain text and should be wrapped in a <pre>
+	 */
+	public const CONTEXT_PRE = 'pre';
+
 	/**
 	 * Get a stable unique name to identify this differ in a cache key.
 	 */

tests/phpunit/includes/diff/TextDiffer/ManifoldTextDifferTest.php

@@ -24,9 +24,9 @@ class ManifoldTextDifferTest extends MediaWikiIntegrationTestCase {
 
 	public function testGetFormats() {
 		if ( extension_loaded( 'wikidiff2' ) ) {
-			$formats = [ 'table', 'inline' ];
+			$formats = [ 'table', 'inline', 'unified' ];
 		} else {
-			$formats = [ 'table' ];
+			$formats = [ 'table', 'unified' ];
 		}
 		$this->assertSame(
 			$formats,
@@ -85,12 +85,14 @@ class ManifoldTextDifferTest extends MediaWikiIntegrationTestCase {
 		$differ = $this->createDiffer( [
 			'ExternalDiffEngine' => __DIR__ . '/externalDiffTest.sh'
 		] );
-		$result = $differ->renderBatch( 'foo', 'bar', [ 'table', 'inline', 'external' ] );
+		$result = $differ->renderBatch( 'foo', 'bar',
+			[ 'table', 'inline', 'external', 'unified' ] );
 		$this->assertSame(
 			[
 				'table' => TextDifferData::WIKIDIFF2_TABLE,
 				'inline' => TextDifferData::WIKIDIFF2_INLINE,
-				'external' => TextDifferData::EXTERNAL
+				'external' => TextDifferData::EXTERNAL,
+				'unified' => TextDifferData::PHP_UNIFIED
 			],
 			$result
 		);
@@ -100,6 +102,7 @@ class ManifoldTextDifferTest extends MediaWikiIntegrationTestCase {
 		return [
 			[ 'table', false ],
 			[ 'external', false ],
+			[ 'unified', true ]
 		];
 	}
 
@@ -114,7 +117,7 @@ class ManifoldTextDifferTest extends MediaWikiIntegrationTestCase {
 		] );
 		$result = $differ->addRowWrapper( $format, 'foo' );
 		if ( $isWrap ) {
-			$this->assertSame( '<tr><td colspan="4">foo</td></tr>', $result );
+			$this->assertSame( '<tr><td colspan="4"><pre>foo</pre></td></tr>', $result );
 		} else {
 			$this->assertSame( 'foo', $result );
 		}

tests/phpunit/includes/diff/TextDiffer/PhpTextDifferTest.php

@@ -39,6 +39,13 @@ class PhpTextDifferTest extends MediaWikiIntegrationTestCase {
 					'table' => TextDifferData::PHP_TABLE,
 				]
 			],
+			'multiple formats' => [
+				[ 'table', 'unified' ],
+				[
+					'table' => TextDifferData::PHP_TABLE,
+					'unified' => TextDifferData::PHP_UNIFIED,
+				]
+			],
 		];
 	}
 

tests/phpunit/includes/diff/TextDiffer/TextDifferData.php

@@ -8,6 +8,11 @@ class TextDifferData {
 	public const PHP_TABLE = '<tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l1"><!--LINE 1--></td>
 <td colspan="2" class="diff-lineno"><!--LINE 1--></td></tr>
 <tr><td class="diff-marker" data-marker="−"></td><td class="diff-deletedline diff-side-deleted"><div><del class="diffchange diffchange-inline">foo</del></div></td><td class="diff-marker" data-marker="+"></td><td class="diff-addedline diff-side-added"><div><ins class="diffchange diffchange-inline">bar</ins></div></td></tr>
+';
+
+	public const PHP_UNIFIED = '@@ -1,1 +1,1 @@
+-foo
++bar
 ';
 
 	public const WIKIDIFF2_TABLE = '<tr>