fixed #4 return type detection of [self|static]::getValues()

src/EnumDynamicReturnTypeExtension.php

@@ -7,6 +7,7 @@
 use PhpParser\Node\Expr\StaticCall;
 use PHPStan\Analyser\Scope;
 use PHPStan\Reflection\MethodReflection;
+use PHPStan\Reflection\ParametersAcceptorSelector;
 use PHPStan\Type\ArrayType;
 use PHPStan\Type\Constant\ConstantArrayType;
 use PHPStan\Type\ConstantTypeHelper;
@@ -81,22 +82,30 @@ public function getTypeFromStaticMethodCall(
         StaticCall $staticCall,
         Scope $scope
     ): Type {
-        $callClass   = $staticCall->class->toString();
-        $methodLower = strtolower($methodReflection->getName());
+        $callClass = $staticCall->class->toString();
+
+        // Can't detect possible types on static::*()
+        // as it depends on defined enumerators of unknown inherited classes
+        if ($callClass === 'static') {
+            return ParametersAcceptorSelector::selectSingle($methodReflection->getVariants())->getReturnType();
+        }
 
-        return $this->staticMethods[$methodLower]($callClass);
+        if ($callClass === 'self') {
+            $callClass = $scope->getClassReflection()->getName();
+        }
+
+        $methodLower = strtolower($methodReflection->getName());
+        return $this->objectMethods[$methodLower]($callClass);
     }
 
     public function getTypeFromMethodCall(
         MethodReflection $methodReflection,
         MethodCall $methodCall,
         Scope $scope
     ): Type {
-        $callType    = $scope->getType($methodCall->var);
-        $callClasses = $callType->getReferencedClasses();
         $methodLower = strtolower($methodReflection->getName());
         $returnTypes = [];
-        foreach ($callClasses as $callClass) {
+        foreach ($scope->getType($methodCall->var)->getReferencedClasses() as $callClass) {
             $returnTypes[] = $this->objectMethods[$methodLower]($callClass);
         }
 

tests/integration/data/EnumGetValuesReturnType-3.json

@@ -1,12 +1,22 @@
 [
     {
-        "message": "Method MabeEnum\\PHPStan\\tests\\integration\\data\\EnumGetValuesReturnType\\Example::staticMethodFail() should return array<int, bool> but returns array<int, float|int|string>.",
+        "message": "Method MabeEnum\\PHPStan\\tests\\integration\\data\\EnumGetValuesReturnType\\Example::staticMethodFail() should return array<int, null> but returns array<int, float|int|string>.",
         "line": 24,
         "ignorable": true
     },
     {
-        "message": "Method MabeEnum\\PHPStan\\tests\\integration\\data\\EnumGetValuesReturnType\\Example::objectMethodFail() should return array<int, bool> but returns array<int, float|int|string>.",
+        "message": "Method MabeEnum\\PHPStan\\tests\\integration\\data\\EnumGetValuesReturnType\\Example::objectMethodFail() should return array<int, null> but returns array<int, float|int|string>.",
         "line": 36,
         "ignorable": true
+    },
+    {
+        "message": "Method MabeEnum\\PHPStan\\tests\\integration\\data\\EnumGetValuesReturnType\\MyEnum::selfGetValuesFail() should return array<int, null> but returns array<int, int|string>.",
+        "line": 54,
+        "ignorable": true
+    },
+    {
+        "message": "Method MabeEnum\\PHPStan\\tests\\integration\\data\\EnumGetValuesReturnType\\MyInheritedEnum::inheritSelfGetValuesFail() should return array<int, null> but returns array<int, float|int|string>.",
+        "line": 77,
+        "ignorable": true
     }
 ]

tests/integration/data/EnumGetValuesReturnType-7.json

@@ -0,0 +1,12 @@
+[
+    {
+        "message": "Method MabeEnum\\PHPStan\\tests\\integration\\data\\EnumGetValuesReturnType\\MyEnum::staticGetValuesFail() should return array<int, null> but returns array<int, array|bool|float|int|string|null>.",
+        "line": 60,
+        "ignorable": true
+    },
+    {
+        "message": "Method MabeEnum\\PHPStan\\tests\\integration\\data\\EnumGetValuesReturnType\\MyInheritedEnum::inheritStaticGetValuesFail() should return array<int, null> but returns array<int, array|bool|float|int|string|null>.",
+        "line": 83,
+        "ignorable": true
+    }
+]

tests/integration/data/EnumGetValuesReturnType.php

@@ -18,7 +18,7 @@ public static function staticMethodValid(): array
         return MyInheritedEnum::getValues();
     }
 
-    /** @return array<int, bool> */
+    /** @return array<int, null> */
     public static function staticMethodFail(): array
     {
         return MyInheritedEnum::getValues();
@@ -30,7 +30,7 @@ public static function objectMethodValid(): array
         return MyInheritedEnum::STR()->getValues();
     }
 
-    /** @return array<int, bool> */
+    /** @return array<int, null> */
     public static function objectMethodFail(): array
     {
         return MyInheritedEnum::STR()->getValues();
@@ -41,9 +41,45 @@ class MyEnum extends Enum
 {
     const STR = 'str';
     const INT = 1;
+
+    /** @return array<int, int|string> */
+    public static function selfGetValuesValid(): array
+    {
+        return self::getValues();
+    }
+
+    /** @return array<int, null> */
+    public static function selfGetValuesFail(): array
+    {
+        return self::getValues();
+    }
+
+    /** @return array<int, null> */
+    public static function staticGetValuesFail(): array
+    {
+        return static::getValues();
+    }
 }
 
 class MyInheritedEnum extends MyEnum
 {
     const FLOAT = 1.1;
+
+    /** @return array<int, float|int|string> */
+    public static function inheritSelfGetValuesValid(): array
+    {
+        return self::getValues();
+    }
+
+    /** @return array<int, null> */
+    public static function inheritSelfGetValuesFail(): array
+    {
+        return self::getValues();
+    }
+
+    /** @return array<int, null> */
+    public static function inheritStaticGetValuesFail(): array
+    {
+        return static::getValues();
+    }
 }