identicalClassComparison: fix callable false positive (#81)

shipmonk-rnd · Feb 3, 2023 · 14691a8 · 14691a8
1 parent 24142f7
commit 14691a8
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Showing 2 changed files with 18 additions and 13 deletions.
diff --git a/src/Rule/ForbidIdenticalClassComparisonRule.php b/src/Rule/ForbidIdenticalClassComparisonRule.php
@@ -11,6 +11,7 @@
 use PHPStan\Analyser\Scope;
 use PHPStan\Reflection\ReflectionProvider;
 use PHPStan\Rules\Rule;
+use PHPStan\Type\CallableType;
 use PHPStan\Type\Constant\ConstantBooleanType;
 use PHPStan\Type\MixedType;
 use PHPStan\Type\ObjectType;
@@ -25,6 +26,11 @@ class ForbidIdenticalClassComparisonRule implements Rule
 {
 
     private const DEFAULT_BLACKLIST = [DateTimeInterface::class];
+    private const IGNORED_TYPES = [
+        MixedType::class, // mixed is "maybe" accepted by any (denied) class
+        ObjectWithoutClassType::class, // object is "maybe" accepted by any (denied) class
+        CallableType::class, // any non-final class descendant can have __invoke method causing it to be "maybe" accepted by any (denied) class
+    ];
 
     /**
      * @var array<int, class-string<object>>
@@ -75,13 +81,10 @@ public function processNode(Node $node, Scope $scope): array
             return []; // always-true or always-false, already reported by native PHPStan (like $a === $a)
         }
 
-        if (
-            $leftType instanceof MixedType
-            || $leftType instanceof ObjectWithoutClassType
-            || $rightType instanceof MixedType
-            || $rightType instanceof ObjectWithoutClassType
-        ) {
-            return []; // those may contain forbidden class, but that is too strict
+        foreach (self::IGNORED_TYPES as $ignoredType) {
+            if ($leftType instanceof $ignoredType || $rightType instanceof $ignoredType) {
+                return [];
+            }
         }
 
         $errors = [];

diff --git a/tests/Rule/data/ForbidIdenticalClassComparisonRule/code.php b/tests/Rule/data/ForbidIdenticalClassComparisonRule/code.php
@@ -23,14 +23,16 @@ public function testNonObject(?DateTimeImmutable $a, string $b): void
         }
     }
 
-    public function testMixed(DateTimeImmutable $a, mixed $b): void
-    {
-        $a === $b;
-    }
-
-    public function testAnyObject(DateTimeImmutable $a, object $b): void
+    public function testProblematicTypes(
+        DateTimeImmutable $a,
+        mixed $b,
+        object $c,
+        callable $d
+    ): void
     {
         $a === $b;
+        $a === $c;
+        $a === $d;
     }
 
     public function testRegular(DateTimeImmutable $a, DateTimeImmutable $b): void