[TypeDeclaration] Add array type from returned method call types (#6277)

rules-tests/TypeDeclaration/Rector/ClassMethod/AddArrayReturnDocTypeRector/Fixture/add_from_child.php.inc

@@ -0,0 +1,55 @@
+<?php
+
+namespace Rector\Tests\TypeDeclaration\Rector\ClassMethod\AddArrayReturnDocTypeRector\Fixture;
+
+final class AddFromChild
+{
+    public function getData(Nested $nested)
+    {
+        return $nested->getData();
+    }
+}
+
+final class Nested
+{
+    public function getData()
+    {
+        return [
+            'key',
+            'value'
+        ];
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\TypeDeclaration\Rector\ClassMethod\AddArrayReturnDocTypeRector\Fixture;
+
+final class AddFromChild
+{
+    /**
+     * @return string[]
+     */
+    public function getData(Nested $nested)
+    {
+        return $nested->getData();
+    }
+}
+
+final class Nested
+{
+    /**
+     * @return string[]
+     */
+    public function getData()
+    {
+        return [
+            'key',
+            'value'
+        ];
+    }
+}
+
+?>

rules-tests/TypeDeclaration/Rector/FunctionLike/ReturnTypeDeclarationRector/Fixture/skip_switch_returns.php.inc

@@ -2,7 +2,7 @@
 
 namespace Rector\Tests\TypeDeclaration\Rector\FunctionLike\ReturnTypeDeclarationRector\Fixture;
 
-class SkipSwtichReturns
+final class SkipSwitchReturns
 {
     public function someFunction($value)
     {

rules/TypeDeclaration/TypeInferer/ReturnTypeInferer/ReturnedNodesReturnTypeInferer.php

@@ -6,6 +6,7 @@ namespace Rector\TypeDeclaration\TypeInferer\ReturnTypeInferer;
 
 use PhpParser\Node;
 use PhpParser\Node\Expr\Closure;
+use PhpParser\Node\Expr\MethodCall;
 use PhpParser\Node\FunctionLike;
 use PhpParser\Node\Stmt\Class_;
 use PhpParser\Node\Stmt\ClassLike;
@@ -13,12 +14,12 @@ use PhpParser\Node\Stmt\ClassMethod;
 use PhpParser\Node\Stmt\Function_;
 use PhpParser\Node\Stmt\Interface_;
 use PhpParser\Node\Stmt\Return_;
-use PhpParser\Node\Stmt\Switch_;
 use PhpParser\Node\Stmt\Trait_;
 use PhpParser\NodeTraverser;
 use PHPStan\Type\MixedType;
 use PHPStan\Type\Type;
 use PHPStan\Type\VoidType;
+use Rector\NodeCollector\NodeCollector\NodeRepository;
 use Rector\NodeTypeResolver\Node\AttributeKey;
 use Rector\NodeTypeResolver\NodeTypeResolver;
 use Rector\NodeTypeResolver\PHPStan\Type\TypeFactory;
@@ -29,11 +30,6 @@ use Symplify\Astral\NodeTraverser\SimpleCallableNodeTraverser;
 
 final class ReturnedNodesReturnTypeInferer implements ReturnTypeInfererInterface
 {
-    /**
-     * @var Type[]
-     */
-    private $types = [];
-
     /**
      * @var SilentVoidResolver
      */
@@ -59,18 +55,25 @@ final class ReturnedNodesReturnTypeInferer implements ReturnTypeInfererInterface
      */
     private $splArrayFixedTypeNarrower;
 
+    /**
+     * @var NodeRepository
+     */
+    private $nodeRepository;
+
     public function __construct(
         SilentVoidResolver $silentVoidResolver,
         NodeTypeResolver $nodeTypeResolver,
         SimpleCallableNodeTraverser $simpleCallableNodeTraverser,
         TypeFactory $typeFactory,
-        SplArrayFixedTypeNarrower $splArrayFixedTypeNarrower
+        SplArrayFixedTypeNarrower $splArrayFixedTypeNarrower,
+        NodeRepository $nodeRepository
     ) {
         $this->silentVoidResolver = $silentVoidResolver;
         $this->nodeTypeResolver = $nodeTypeResolver;
         $this->simpleCallableNodeTraverser = $simpleCallableNodeTraverser;
         $this->typeFactory = $typeFactory;
         $this->splArrayFixedTypeNarrower = $splArrayFixedTypeNarrower;
+        $this->nodeRepository = $nodeRepository;
     }
 
     /**
@@ -88,25 +91,28 @@ final class ReturnedNodesReturnTypeInferer implements ReturnTypeInfererInterface
             return new MixedType();
         }
 
-        $this->types = [];
+        $types = [];
 
         $localReturnNodes = $this->collectReturns($functionLike);
         if ($localReturnNodes === []) {
             return $this->resolveNoLocalReturnNodes($classLike, $functionLike);
         }
 
-        $hasSilentVoid = $this->silentVoidResolver->hasSilentVoid($functionLike);
-
         foreach ($localReturnNodes as $localReturnNode) {
             $returnedExprType = $this->nodeTypeResolver->getStaticType($localReturnNode);
-            $this->types[] = $this->splArrayFixedTypeNarrower->narrow($returnedExprType);
+
+            if ($returnedExprType instanceof MixedType) {
+                $returnedExprType = $this->inferFromReturnedMethodCall($localReturnNode);
             }
 
-        if ($hasSilentVoid) {
-            $this->types[] = new VoidType();
+            $types[] = $this->splArrayFixedTypeNarrower->narrow($returnedExprType);
         }
 
-        return $this->typeFactory->createMixedPassedOrUnionType($this->types);
+        if ($this->silentVoidResolver->hasSilentVoid($functionLike)) {
+            $types[] = new VoidType();
+        }
+
+        return $this->typeFactory->createMixedPassedOrUnionType($types);
     }
 
     public function getPriority(): int
@@ -124,10 +130,6 @@ final class ReturnedNodesReturnTypeInferer implements ReturnTypeInfererInterface
         $this->simpleCallableNodeTraverser->traverseNodesWithCallable((array) $functionLike->getStmts(), function (
             Node $node
         ) use (&$returns): ?int {
-            if ($node instanceof Switch_) {
-                $this->processSwitch($node);
-            }
-
             // skip Return_ nodes in nested functions or switch statements
             if ($node instanceof FunctionLike) {
                 return NodeTraverser::DONT_TRAVERSE_CHILDREN;
@@ -155,17 +157,6 @@ final class ReturnedNodesReturnTypeInferer implements ReturnTypeInfererInterface
         return new MixedType();
     }
 
-    private function processSwitch(Switch_ $switch): void
-    {
-        foreach ($switch->cases as $case) {
-            if ($case->cond === null) {
-                return;
-            }
-        }
-
-        $this->types[] = new VoidType();
-    }
-
     private function isAbstractMethod(ClassLike $classLike, FunctionLike $functionLike): bool
     {
         if ($functionLike instanceof ClassMethod && $functionLike->isAbstract()) {
@@ -177,4 +168,18 @@ final class ReturnedNodesReturnTypeInferer implements ReturnTypeInfererInterface
         }
         return $classLike->isAbstract();
     }
+
+    private function inferFromReturnedMethodCall(Return_ $return): Type
+    {
+        if (! $return->expr instanceof MethodCall) {
+            return new MixedType();
+        }
+
+        $classMethod = $this->nodeRepository->findClassMethodByMethodCall($return->expr);
+        if (! $classMethod instanceof ClassMethod) {
+            return new MixedType();
+        }
+
+        return $this->inferFunctionLike($classMethod);
+    }
 }

rules/TypeDeclaration/TypeInferer/SilentVoidResolver.php

@@ -109,20 +109,22 @@ final class SilentVoidResolver
 
     private function isSwitchWithAlwaysReturn(Switch_ $switch): bool
     {
-        $casesWithReturn = 0;
+        $hasDefault = false;
+
         foreach ($switch->cases as $case) {
-            foreach ($case->stmts as $caseStmt) {
-                if (! $caseStmt instanceof Return_) {
-                    continue;
+            if ($case->cond === null) {
+                $hasDefault = true;
+            }
         }
 
-                ++$casesWithReturn;
-                break;
-            }
+        if (! $hasDefault) {
+            return false;
         }
 
+        $casesWithReturnCount = $this->resolveReturnCount($switch);
+
         // has same amount of returns as switches
-        return count($switch->cases) === $casesWithReturn;
+        return count($switch->cases) === $casesWithReturnCount;
     }
 
     private function isTryCatchAlwaysReturn(TryCatch $tryCatch): bool
@@ -146,4 +148,22 @@ final class SilentVoidResolver
     {
         return $this->betterNodeFinder->hasInstancesOf($functionLike, [Throw_::class]);
     }
+
+    private function resolveReturnCount(Switch_ $switch): int
+    {
+        $casesWithReturnCount = 0;
+
+        foreach ($switch->cases as $case) {
+            foreach ($case->stmts as $caseStmt) {
+                if (! $caseStmt instanceof Return_) {
+                    continue;
+                }
+
+                ++$casesWithReturnCount;
+                break;
+            }
+        }
+
+        return $casesWithReturnCount;
+    }
 }