Add tests for @pure-unless-parameter-passed

Author: zonuexe

tests/PHPStan/Rules/Pure/PureFunctionRuleTest.php

@@ -378,4 +378,32 @@ public function testPureUnlessCallableIsImpurePhp84(): void
 		]);
 	}
 
+	public function testPureUnlessParameterPassed(): void
+	{
+		$this->analyse([__DIR__ . '/data/pure-unless-parameter-passed.php'], [
+			[
+				'Possibly impure call to function PureUnlessParameterPassedFunction\myReplace() in pure function PureUnlessParameterPassedFunction\purePassingByRef().',
+				44,
+			],
+			[
+				'Possibly impure call to function PureUnlessParameterPassedFunction\myReplacePhpstanAlias() in pure function PureUnlessParameterPassedFunction\purePassingByRefAlias().',
+				62,
+			],
+		]);
+	}
+
+	public function testPureUnlessParameterPassedBuiltin(): void
+	{
+		$this->analyse([__DIR__ . '/data/pure-unless-parameter-passed-builtin.php'], [
+			[
+				'Possibly impure call to function str_replace() in pure function PureUnlessParameterPassedBuiltin\pureStrReplaceWithCount().',
+				22,
+			],
+			[
+				'Possibly impure call to function preg_match() in pure function PureUnlessParameterPassedBuiltin\purePregMatchWithMatches().',
+				40,
+			],
+		]);
+	}
+
 }

tests/PHPStan/Rules/Pure/data/pure-unless-parameter-passed-builtin.php

@@ -0,0 +1,41 @@
+<?php declare(strict_types = 1);
+
+namespace PureUnlessParameterPassedBuiltin;
+
+/**
+ * @phpstan-pure
+ */
+function pureStrReplaceWithoutCount(string $s): string
+{
+	// The by-ref $count is omitted, so str_replace() is pure.
+	return str_replace('a', 'b', $s);
+}
+
+/**
+ * @phpstan-pure
+ */
+function pureStrReplaceWithCount(string $s): string
+{
+	// The by-ref $count is passed, so str_replace() is possibly impure.
+	$count = 0;
+
+	return str_replace('a', 'b', $s, $count);
+}
+
+/**
+ * @phpstan-pure
+ */
+function purePregMatchWithoutMatches(string $s): int
+{
+	// The by-ref $matches is omitted, so preg_match() is pure.
+	return (int) preg_match('/a/', $s);
+}
+
+/**
+ * @phpstan-pure
+ */
+function purePregMatchWithMatches(string $s): int
+{
+	// The by-ref $matches is passed, so preg_match() is possibly impure.
+	return (int) preg_match('/a/', $s, $matches);
+}

tests/PHPStan/Rules/Pure/data/pure-unless-parameter-passed.php

@@ -0,0 +1,63 @@
+<?php declare(strict_types = 1);
+
+namespace PureUnlessParameterPassedFunction;
+
+/**
+ * @param-out int $count
+ * @pure-unless-parameter-passed $count
+ */
+function myReplace(string $subject, int &$count = 0): string
+{
+	$count = 1;
+
+	return $subject;
+}
+
+/**
+ * @param-out int $count
+ * @phpstan-pure-unless-parameter-passed $count
+ */
+function myReplacePhpstanAlias(string $subject, int &$count = 0): string
+{
+	$count = 1;
+
+	return $subject;
+}
+
+/**
+ * @phpstan-pure
+ */
+function pureNotPassingByRef(string $s): string
+{
+	// $count is omitted, so myReplace() stays pure.
+	return myReplace($s);
+}
+
+/**
+ * @phpstan-pure
+ */
+function purePassingByRef(string $s): string
+{
+	// $count is passed, so myReplace() is possibly impure.
+	$count = 0;
+
+	return myReplace($s, $count);
+}
+
+/**
+ * @phpstan-pure
+ */
+function pureNotPassingByRefAlias(string $s): string
+{
+	return myReplacePhpstanAlias($s);
+}
+
+/**
+ * @phpstan-pure
+ */
+function purePassingByRefAlias(string $s): string
+{
+	$count = 0;
+
+	return myReplacePhpstanAlias($s, $count);
+}