1 files changed, 102 insertions, 0 deletions
diff --git a/MLEB/Translate/src/Validation/Validators/NewlineValidator.php b/MLEB/Translate/src/Validation/Validators/NewlineValidator.php
new file mode 100644
index 00000000..36525569
--- /dev/null
+++ b/MLEB/Translate/src/Validation/Validators/NewlineValidator.php
@@ -0,0 +1,102 @@
+<?php
+declare( strict_types = 1 );
+
+namespace MediaWiki\Extension\Translate\Validation\Validators;
+
+use MediaWiki\Extension\Translate\Validation\MessageValidator;
+use MediaWiki\Extension\Translate\Validation\ValidationIssue;
+use MediaWiki\Extension\Translate\Validation\ValidationIssues;
+use TMessage;
+
+/**
+ * Ensures that the translation has the same number of newlines as the source
+ * message at the beginning of the string.
+ * @author Abijeet Patro
+ * @license GPL-2.0-or-later
+ * @since 2019.09
+ */
+class NewlineValidator implements MessageValidator {
+	public function getIssues( TMessage $message, string $targetLanguage ): ValidationIssues {
+		$translation = $message->translation();
+		$definition = $message->definition();
+
+		$definitionStartNewline = $this->getStartingNewLinesCount( $definition );
+		$translationStartNewline = $this->getStartingNewLinesCount( $translation );
+
+		$failingChecks = $this->validateStartingNewline(
+			$definitionStartNewline, $translationStartNewline
+		);
+
+		return $this->createIssues( $failingChecks );
+	}
+
+	protected function getStartingNewLinesCount( string $str ): int {
+		return strspn( $str, "\n" );
+	}
+
+	protected function getEndingNewLineCount( string $str ): int {
+		return strspn( strrev( $str ), "\n" );
+	}
+
+	protected function validateStartingNewline(
+		int $definitionStartNewline,
+		int $translationStartNewline
+	): array {
+		$failingChecks = [];
+		if ( $definitionStartNewline < $translationStartNewline ) {
+			// Extra whitespace at beginning
+			$failingChecks[] = [
+				'extra-start',
+				$translationStartNewline - $definitionStartNewline
+			];
+		} elseif ( $definitionStartNewline > $translationStartNewline ) {
+			// Missing whitespace at beginning
+			$failingChecks[] = [
+				'missing-start',
+				$definitionStartNewline - $translationStartNewline
+			];
+		}
+
+		return $failingChecks;
+	}
+
+	protected function validateEndingNewline(
+		int $definitionEndNewline,
+		int $translationEndNewline
+	): array {
+		$failingChecks = [];
+		if ( $definitionEndNewline < $translationEndNewline ) {
+			// Extra whitespace at end
+			$failingChecks[] = [
+				'extra-end',
+				$translationEndNewline - $definitionEndNewline
+			];
+		} elseif ( $definitionEndNewline > $translationEndNewline ) {
+			// Missing whitespace at end
+			$failingChecks[] = [
+				'missing-end',
+				$definitionEndNewline - $translationEndNewline
+			];
+		}
+
+		return $failingChecks;
+	}
+
+	protected function createIssues( array $failingChecks ): ValidationIssues {
+		$issues = new ValidationIssues();
+		foreach ( $failingChecks as [ $subType, $count ] ) {
+			$issue = new ValidationIssue(
+				'newline',
+				$subType,
+				"translate-checks-newline-$subType",
+				[ 'COUNT', $count ]
+			);
+
+			$issues->add( $issue );
+		}
+
+		return $issues;
+	}
+}
+
+class_alias( NewlineValidator::class, '\MediaWiki\Extensions\Translate\NewlineValidator' );