file_get_contents is definitely an impure function

phpstan · Apr 3, 2024 · 2b5b317 · 2b5b317
1 parent c16e491
commit 2b5b317
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Showing 6 changed files with 8 additions and 32 deletions.
diff --git a/bin/functionMetadata_original.php b/bin/functionMetadata_original.php
@@ -79,6 +79,7 @@
 	'fgetcsv' => ['hasSideEffects' => true],
 	'fgets' => ['hasSideEffects' => true],
 	'fgetss' => ['hasSideEffects' => true],
+	'file_get_contents' => ['hasSideEffects' => true],
 	'file_put_contents' => ['hasSideEffects' => true],
 	'flock' => ['hasSideEffects' => true],
 	'fopen' => ['hasSideEffects' => true],

diff --git a/bin/generate-function-metadata.php b/bin/generate-function-metadata.php
@@ -85,6 +85,7 @@ public function enterNode(Node $node)
 					'random_int',
 					'connection_aborted',
 					'connection_status',
+					'file_get_contents',
 				], true)) {
 					continue;
 				}

diff --git a/resources/functionMetadata.php b/resources/functionMetadata.php
@@ -878,7 +878,7 @@
 	'fgetss' => ['hasSideEffects' => true],
 	'file' => ['hasSideEffects' => false],
 	'file_exists' => ['hasSideEffects' => false],
-	'file_get_contents' => ['hasSideEffects' => false],
+	'file_get_contents' => ['hasSideEffects' => true],
 	'file_put_contents' => ['hasSideEffects' => true],
 	'fileatime' => ['hasSideEffects' => false],
 	'filectime' => ['hasSideEffects' => false],

diff --git a/src/Rules/Functions/CallToFunctionStatementWithoutSideEffectsRule.php b/src/Rules/Functions/CallToFunctionStatementWithoutSideEffectsRule.php
@@ -20,10 +20,9 @@ class CallToFunctionStatementWithoutSideEffectsRule implements Rule
 {
 
 	private const SIDE_EFFECT_FLIP_PARAMETERS = [
-		// functionName => [name, pos, testName, defaultHasSideEffect]
-		'file_get_contents' => ['context', 2, 'isNotNull', false],
-		'print_r' => ['return', 1, 'isTruthy', true],
-		'var_export' => ['return', 1, 'isTruthy', true],
+		// functionName => [name, pos, testName]
+		'print_r' => ['return', 1, 'isTruthy'],
+		'var_export' => ['return', 1, 'isTruthy'],
 	];
 
 	public function __construct(private ReflectionProvider $reflectionProvider)
@@ -68,7 +67,6 @@ public function processNode(Node $node, Scope $scope): array
 				$flipParameterName,
 				$flipParameterPosition,
 				$testName,
-				$defaultHasSideEffect,
 			] = self::SIDE_EFFECT_FLIP_PARAMETERS[$functionName];
 
 			$sideEffectFlipped = false;
@@ -102,7 +100,7 @@ public function processNode(Node $node, Scope $scope): array
 				}
 			}
 
-			if ($sideEffectFlipped xor $defaultHasSideEffect) {
+			if (!$sideEffectFlipped) {
 				return [];
 			}
 

diff --git a/tests/PHPStan/Analyser/data/filesystem-functions.php b/tests/PHPStan/Analyser/data/filesystem-functions.php
@@ -59,7 +59,7 @@ public function test3($fh): void
 	public function test4(string $path): void
 	{
 		if (file_get_contents($path) === 'data') {
-			assertType('\'data\'', file_get_contents($path));
+			assertType('string|false', file_get_contents($path));
 			file_put_contents($path, 'other');
 			assertType('string|false', file_get_contents($path));
 		}

diff --git a/tests/PHPStan/Rules/Functions/CallToFunctionStatementWithoutSideEffectsRuleTest.php b/tests/PHPStan/Rules/Functions/CallToFunctionStatementWithoutSideEffectsRuleTest.php
@@ -24,14 +24,6 @@ public function testRule(): void
 				'Call to function sprintf() on a separate line has no effect.',
 				13,
 			],
-			[
-				'Call to function file_get_contents() on a separate line has no effect.',
-				14,
-			],
-			[
-				'Call to function file_get_contents() on a separate line has no effect.',
-				22,
-			],
 			[
 				'Call to function var_export() on a separate line has no effect.',
 				24,
@@ -47,22 +39,6 @@ public function testRule(): void
 		}
 
 		$this->analyse([__DIR__ . '/data/function-call-statement-no-side-effects-8.0.php'], [
-			[
-				'Call to function file_get_contents() on a separate line has no effect.',
-				15,
-			],
-			[
-				'Call to function file_get_contents() on a separate line has no effect.',
-				16,
-			],
-			[
-				'Call to function file_get_contents() on a separate line has no effect.',
-				17,
-			],
-			[
-				'Call to function file_get_contents() on a separate line has no effect.',
-				18,
-			],
 			[
 				'Call to function var_export() on a separate line has no effect.',
 				19,