RegularExpressionPatternRule: fix false positive in preg_quote() handling

Author: staabm

src/Type/Php/RegexExpressionHelper.php

@@ -40,12 +40,16 @@ public function __construct(private Scope $scope)
 
 			public function resolve(Expr $expr): Type
 			{
+				// assume preg_quote() cannot create capturing groups or contain meta characters.
+				// replace it with a pattern which matches anything, does not affect $matches results
+				// and does not produce regex errors when followed by a quantifier.
+				// this allows us to turn string concatenations with preg_quote() into static analyzable strings.
 				if (
 					$expr instanceof Expr\FuncCall
 					&& $expr->name instanceof Name
 					&& $expr->name->toLowerString() === 'preg_quote'
 				) {
-					return new ConstantStringType('.*');
+					return new ConstantStringType('(?:.*)');
 				}
 
 				if ($expr instanceof Concat) {

tests/PHPStan/Rules/Regexp/RegularExpressionPatternRuleTest.php

@@ -119,27 +119,27 @@ public function testValidRegexPatternBefore73(): void
 					43,
 				],
 				[
-					'Regex pattern is invalid: Delimiter must not be alphanumeric or backslash in pattern: nok.*',
+					'Regex pattern is invalid: Delimiter must not be alphanumeric or backslash in pattern: nok(?:.*)',
 					57,
 				],
 				[
-					'Regex pattern is invalid: Delimiter must not be alphanumeric or backslash in pattern: nok.*',
+					'Regex pattern is invalid: Delimiter must not be alphanumeric or backslash in pattern: nok(?:.*)',
 					58,
 				],
 				[
-					'Regex pattern is invalid: Compilation failed: missing ) at offset 3 in pattern: ~(.*~',
+					'Regex pattern is invalid: Compilation failed: missing ) at offset 7 in pattern: ~((?:.*)~',
 					59,
 				],
 				[
-					'Regex pattern is invalid: Delimiter must not be alphanumeric or backslash in pattern: nok.*nono',
+					'Regex pattern is invalid: Delimiter must not be alphanumeric or backslash in pattern: nok(?:.*)nono',
 					61,
 				],
 				[
-					'Regex pattern is invalid: Delimiter must not be alphanumeric or backslash in pattern: nok.*nope',
+					'Regex pattern is invalid: Delimiter must not be alphanumeric or backslash in pattern: nok(?:.*)nope',
 					62,
 				],
 				[
-					'Regex pattern is invalid: Compilation failed: missing ) at offset 3 in pattern: ~(.*~',
+					'Regex pattern is invalid: Compilation failed: missing ) at offset 7 in pattern: ~((?:.*)~',
 					63,
 				],
 			],
@@ -249,27 +249,27 @@ public function testValidRegexPatternAfter73(): void
 					43,
 				],
 				[
-					sprintf('Regex pattern is invalid: Delimiter must not be %s in pattern: nok.*', $messagePart),
+					sprintf('Regex pattern is invalid: Delimiter must not be %s in pattern: nok(?:.*)', $messagePart),
 					57,
 				],
 				[
-					sprintf('Regex pattern is invalid: Delimiter must not be %s in pattern: nok.*', $messagePart),
+					sprintf('Regex pattern is invalid: Delimiter must not be %s in pattern: nok(?:.*)', $messagePart),
 					58,
 				],
 				[
-					'Regex pattern is invalid: Compilation failed: missing closing parenthesis at offset 3 in pattern: ~(.*~',
+					'Regex pattern is invalid: Compilation failed: missing closing parenthesis at offset 7 in pattern: ~((?:.*)~',
 					59,
 				],
 				[
-					sprintf('Regex pattern is invalid: Delimiter must not be %s in pattern: nok.*nono', $messagePart),
+					sprintf('Regex pattern is invalid: Delimiter must not be %s in pattern: nok(?:.*)nono', $messagePart),
 					61,
 				],
 				[
-					sprintf('Regex pattern is invalid: Delimiter must not be %s in pattern: nok.*nope', $messagePart),
+					sprintf('Regex pattern is invalid: Delimiter must not be %s in pattern: nok(?:.*)nope', $messagePart),
 					62,
 				],
 				[
-					'Regex pattern is invalid: Compilation failed: missing closing parenthesis at offset 3 in pattern: ~(.*~',
+					'Regex pattern is invalid: Compilation failed: missing closing parenthesis at offset 7 in pattern: ~((?:.*)~',
 					63,
 				],
 			],

tests/PHPStan/Rules/Regexp/data/valid-regex-pattern.php

@@ -70,3 +70,24 @@ public function sayHello(string $s): void
 		preg_replace('![' . preg_quote($s) . ']+!u', $s, $s);
 	}
 }
+
+class Bug11432 {
+	function a(string $str, string $character = ',', bool $trim = false): string
+	{
+		$str = preg_replace('#' . preg_quote($character, '#') . '{2,}#', $character, $str);
+
+		return ($trim) ? trim($str, $character) : $str;
+	}
+	function b(string $str, string $character = ',', bool $trim = false): string
+	{
+		$str = preg_replace('#' . preg_quote($character, '#') . '*#', $character, $str);
+
+		return ($trim) ? trim($str, $character) : $str;
+	}
+	function c(string $str, string $character = ',', bool $trim = false): string
+	{
+		$str = preg_replace('#' . preg_quote($character, '#') . '?#', $character, $str);
+
+		return ($trim) ? trim($str, $character) : $str;
+	}
+}