bug #41463 [Serializer][Validator] Fix not null return from "getCollectionValueTypes" (jderusse)

This PR was merged into the 5.3 branch.

Discussion
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[Serializer][Validator] Fix not null return from "getCollectionValueTypes"

| Q             | A
| ------------- | ---
| Branch?       | 5.3
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Tickets       | -
| License       | MIT
| Doc PR        | -

Currently experimenting `An exception has been thrown during the rendering of a template ("Notice: Undefined offset: 0").`

When a property is an array and PropertyInfo is not able to guess the type of CollectionValue

Commits
-------

c4dcfd1fde Fix not null return from "getCollectionValueTypes"

Author: fabpot

Mapping/Loader/PropertyInfoLoader.php

@@ -119,7 +119,7 @@ public function loadClassMetadata(ClassMetadata $metadata): bool
             }
             if (!$hasTypeConstraint) {
                 if (1 === \count($builtinTypes)) {
-                    if ($types[0]->isCollection() && (null !== $collectionValueType = $types[0]->getCollectionValueTypes())) {
+                    if ($types[0]->isCollection() && \count($collectionValueType = $types[0]->getCollectionValueTypes()) > 0) {
                         [$collectionValueType] = $collectionValueType;
                         $this->handleAllConstraint($property, $allConstraint, $collectionValueType, $metadata);
                     }

Tests/Fixtures/PropertyInfoLoaderEntity.php

@@ -23,6 +23,7 @@ class PropertyInfoLoaderEntity
     public $scalar;
     public $object;
     public $collection;
+    public $collectionOfUnknown;
 
     /**
      * @Assert\Type(type="int")

Tests/Mapping/Loader/PropertyInfoLoaderTest.php

@@ -44,6 +44,7 @@ public function testLoadClassMetadata()
                 'scalar',
                 'object',
                 'collection',
+                'collectionOfUnknown',
                 'alreadyMappedType',
                 'alreadyMappedNotNull',
                 'alreadyMappedNotBlank',
@@ -61,6 +62,7 @@ public function testLoadClassMetadata()
                 [new Type(Type::BUILTIN_TYPE_STRING, true), new Type(Type::BUILTIN_TYPE_INT), new Type(Type::BUILTIN_TYPE_BOOL)],
                 [new Type(Type::BUILTIN_TYPE_OBJECT, true, Entity::class)],
                 [new Type(Type::BUILTIN_TYPE_ARRAY, true, null, true, null, new Type(Type::BUILTIN_TYPE_OBJECT, false, Entity::class))],
+                [new Type(Type::BUILTIN_TYPE_ARRAY, true, null, true)],
                 [new Type(Type::BUILTIN_TYPE_FLOAT, true)], // The existing constraint is float
                 [new Type(Type::BUILTIN_TYPE_STRING, true)],
                 [new Type(Type::BUILTIN_TYPE_STRING, true)],
@@ -81,6 +83,7 @@ public function testLoadClassMetadata()
                 true,
                 true,
                 true,
+                true,
                 false,
                 true
             ))
@@ -135,6 +138,13 @@ public function testLoadClassMetadata()
         $this->assertInstanceOf(TypeConstraint::class, $collectionConstraints[0]->constraints[1]);
         $this->assertSame(Entity::class, $collectionConstraints[0]->constraints[1]->type);
 
+        $collectionOfUnknownMetadata = $classMetadata->getPropertyMetadata('collectionOfUnknown');
+        $this->assertCount(1, $collectionOfUnknownMetadata);
+        $collectionOfUnknownConstraints = $collectionOfUnknownMetadata[0]->getConstraints();
+        $this->assertCount(1, $collectionOfUnknownConstraints);
+        $this->assertInstanceOf(TypeConstraint::class, $collectionOfUnknownConstraints[0]);
+        $this->assertSame('array', $collectionOfUnknownConstraints[0]->type);
+
         $alreadyMappedTypeMetadata = $classMetadata->getPropertyMetadata('alreadyMappedType');
         $this->assertCount(1, $alreadyMappedTypeMetadata);
         $alreadyMappedTypeConstraints = $alreadyMappedTypeMetadata[0]->getConstraints();