fix

Author: staabm

src/Type/Php/RegexArrayShapeMatcher.php

@@ -393,9 +393,9 @@ private function isGroupOptional(RegexCapturingGroup $captureGroup, TrinaryLogic
 
 	private function createGroupValueType(RegexCapturingGroup $captureGroup, TrinaryLogic $wasMatched, int $flags, bool $isTrailingOptional, bool $isLastGroup, bool $matchesAll): Type
 	{
-		$groupValueType = $this->getValueType($captureGroup->getType(), $flags, $matchesAll);
-
 		if ($matchesAll) {
+			$groupValueType = $this->getValueType($captureGroup->getType(), $flags, $matchesAll);
+
 			if (!$isTrailingOptional && $this->containsUnmatchedAsNull($flags, $matchesAll) && !$captureGroup->isOptional()) {
 				$groupValueType = TypeCombinator::removeNull($groupValueType);
 			}
@@ -412,16 +412,22 @@ private function createGroupValueType(RegexCapturingGroup $captureGroup, Trinary
 			return $groupValueType;
 		}
 
+		if (!$isLastGroup && !$this->containsUnmatchedAsNull($flags, $matchesAll) && $captureGroup->isOptional()) {
+			$groupValueType = $this->getValueType(
+				TypeCombinator::union($captureGroup->getType(), new ConstantStringType('')),
+				$flags,
+				$matchesAll
+			);
+		} else {
+			$groupValueType = $this->getValueType($captureGroup->getType(), $flags, $matchesAll);
+		}
+
 		if ($wasMatched->yes()) {
 			if (!$isTrailingOptional && $this->containsUnmatchedAsNull($flags, $matchesAll) && !$captureGroup->isOptional()) {
 				$groupValueType = TypeCombinator::removeNull($groupValueType);
 			}
 		}
 
-		if (!$isLastGroup && !$this->containsUnmatchedAsNull($flags, $matchesAll) && $captureGroup->isOptional()) {
-			$groupValueType = TypeCombinator::union($groupValueType, new ConstantStringType(''));
-		}
-
 		return $groupValueType;
 	}
 

tests/PHPStan/Analyser/nsrt/preg_replace_callback_shapes.php

@@ -22,7 +22,7 @@ function (string $s): void {
 	preg_replace_callback(
 		'/(foo)?(bar)?(baz)?/',
 		function ($matches) {
-			assertType("array{0: array{string, int<0, max>}, 1?: array{'foo', int<0, max>}, 2?: array{'bar', int<0, max>}, 3?: array{'baz', int<0, max>}}", $matches);
+			assertType("array{0: array{string, int<0, max>}, 1?: array{''|'foo', int<0, max>}, 2?: array{''|'bar', int<0, max>}, 3?: array{'baz', int<0, max>}}", $matches);
 			return '';
 		},
 		$s,