Fix bug in Preg::replaceCallbackStrictGroups not detecting null values when used with PREG_OFFSET_CAPTURE

Author: Seldaek

phpstan-baseline.neon

@@ -5,11 +5,6 @@ parameters:
 			count: 1
 			path: src/Preg.php
 
-		-
-			message: "#^Parameter \\#2 \\$matches of static method Composer\\\\Pcre\\\\Preg\\:\\:enforceNonNullMatches\\(\\) expects array\\<int\\|string, string\\|null\\>, array\\<int\\|string, array\\<int, int\\|string\\|null\\>\\|string\\|null\\> given\\.$#"
-			count: 1
-			path: src/Preg.php
-
 		-
 			message: "#^Parameter &\\$matches @param\\-out type of method Composer\\\\Pcre\\\\Preg\\:\\:match\\(\\) expects array\\<int\\|string, string\\|null\\>, \\(int is int \\? array\\<array\\<int, int\\<\\-1, max\\>\\|string\\>\\> \\: \\(int is int \\? array\\<string\\|null\\> \\: \\(int is int \\? array\\<array\\<int, int\\|string\\|null\\>\\> \\: array\\<string\\>\\)\\)\\) given\\.$#"
 			count: 1

src/Preg.php

@@ -391,16 +391,18 @@ private static function checkSetOrder(int $flags): void
     }
 
     /**
-     * @param array<int|string, string|null> $matches
+     * @param array<int|string, string|null|array{string|null, int}> $matches
      * @return array<int|string, string>
      * @throws UnexpectedNullMatchException
      */
     private static function enforceNonNullMatches(string $pattern, array $matches, string $variantMethod)
     {
         foreach ($matches as $group => $match) {
-            if (null === $match) {
-                throw new UnexpectedNullMatchException('Pattern "'.$pattern.'" had an unexpected unmatched group "'.$group.'", make sure the pattern always matches or use '.$variantMethod.'() instead.');
+            if (is_string($match) || (is_array($match) && is_string($match[0]))) {
+                continue;
             }
+
+            throw new UnexpectedNullMatchException('Pattern "'.$pattern.'" had an unexpected unmatched group "'.$group.'", make sure the pattern always matches or use '.$variantMethod.'() instead.');
         }
 
         /** @var array<string> */

tests/PregTests/ReplaceCallbackTest.php

@@ -81,6 +81,26 @@ public function testFailStrictGroups(): void
         }, '123', -1, $count);
     }
 
+    public function testSuccessStrictGroupsOffsets(): void
+    {
+        $result = Preg::replaceCallbackStrictGroups('{(?P<m>\d)(?<matched>a)?}', function ($match) {
+            return strtoupper($match['matched'][0]);
+        }, '3a', -1, $count, PREG_OFFSET_CAPTURE);
+
+        self::assertSame(1, $count);
+        self::assertSame('A', $result);
+    }
+
+    public function testFailsStrictGroupsOffsets(): void
+    {
+        self::expectException(UnexpectedNullMatchException::class);
+        self::expectExceptionMessage('Pattern "{(?P<m>\d)(?<unmatched>a)?}" had an unexpected unmatched group "unmatched", make sure the pattern always matches or use replaceCallback() instead.');
+
+        $result = Preg::replaceCallbackStrictGroups('{(?P<m>\d)(?<unmatched>a)?}', function ($match) {
+            return strtoupper($match['unmatched'][0]);
+        }, '3', -1, $count, PREG_OFFSET_CAPTURE);
+    }
+
     public function testBadPatternThrowsIfWarningsAreNotThrowing(): void
     {
         $this->expectPcreException($pattern = '{(?P<m>d)');