Nullable union template type bound is actually supported

phpstan · Jan 30, 2022 · 1d8b2eb · 1d8b2eb
1 parent e8509b7
commit 1d8b2eb
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Showing 5 changed files with 61 additions and 25 deletions.
diff --git a/src/Rules/Generics/TemplateTypeCheck.php b/src/Rules/Generics/TemplateTypeCheck.php
@@ -22,9 +22,7 @@
 use PHPStan\Type\ObjectType;
 use PHPStan\Type\ObjectWithoutClassType;
 use PHPStan\Type\StringType;
-use PHPStan\Type\Type;
 use PHPStan\Type\TypeAliasResolver;
-use PHPStan\Type\TypeTraverser;
 use PHPStan\Type\UnionType;
 use PHPStan\Type\VerbosityLevel;
 use function array_map;
@@ -95,29 +93,24 @@ public function check(
 				$messages = array_merge($messages, $this->classCaseSensitivityCheck->checkClassNames($classNameNodePairs));
 			}
 
-			TypeTraverser::map($templateTag->getBound(), static function (Type $type, callable $traverse) use (&$messages, $notSupportedBoundMessage, $templateTagName): Type {
-				$boundClass = get_class($type);
-				if (
-					$boundClass === MixedType::class
-					|| $boundClass === ConstantArrayType::class
-					|| $boundClass === ArrayType::class
-					|| $boundClass === StringType::class
-					|| $boundClass === IntegerType::class
-					|| $boundClass === FloatType::class
-					|| $boundClass === BooleanType::class
-					|| $boundClass === ObjectWithoutClassType::class
-					|| $boundClass === ObjectType::class
-					|| $boundClass === GenericObjectType::class
-					|| $type instanceof UnionType
-					|| $type instanceof TemplateType
-				) {
-					return $traverse($type);
-				}
-
-				$messages[] = RuleErrorBuilder::message(sprintf($notSupportedBoundMessage, $templateTagName, $type->describe(VerbosityLevel::typeOnly())))->build();
-
-				return $type;
-			});
+			$boundType = $templateTag->getBound();
+			$boundTypeClass = get_class($boundType);
+			if (
+				$boundTypeClass !== MixedType::class
+				&& $boundTypeClass !== ConstantArrayType::class
+				&& $boundTypeClass !== ArrayType::class
+				&& $boundTypeClass !== StringType::class
+				&& $boundTypeClass !== IntegerType::class
+				&& $boundTypeClass !== FloatType::class
+				&& $boundTypeClass !== BooleanType::class
+				&& $boundTypeClass !== ObjectWithoutClassType::class
+				&& $boundTypeClass !== ObjectType::class
+				&& $boundTypeClass !== GenericObjectType::class
+				&& !$boundType instanceof UnionType
+				&& !$boundType instanceof TemplateType
+			) {
+				$messages[] = RuleErrorBuilder::message(sprintf($notSupportedBoundMessage, $templateTagName, $boundType->describe(VerbosityLevel::typeOnly())))->build();
+			}
 
 			$escapedTemplateTagName = SprintfHelper::escapeFormatString($templateTagName);
 			$genericObjectErrors = $this->genericObjectTypeCheck->check(

diff --git a/tests/PHPStan/Analyser/NodeScopeResolverTest.php b/tests/PHPStan/Analyser/NodeScopeResolverTest.php
@@ -629,6 +629,7 @@ public function dataFileAsserts(): iterable
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-5817.php');
 
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/array-column.php');
+		yield from $this->gatherAssertTypes(__DIR__ . '/data/template-null-bound.php');
 	}
 
 	/**

diff --git a/tests/PHPStan/Analyser/data/template-null-bound.php b/tests/PHPStan/Analyser/data/template-null-bound.php
@@ -0,0 +1,26 @@
+<?php
+
+namespace TemplateNullBound;
+
+use function PHPStan\Testing\assertType;
+
+class Foo
+{
+
+	/**
+	 * @template T of ?int
+	 * @param T $p
+	 * @return T
+	 */
+	public function doFoo(?int $p): ?int
+	{
+		return $p;
+	}
+
+}
+
+function (Foo $f, ?int $i): void {
+	assertType('null', $f->doFoo(null));
+	assertType('int', $f->doFoo(1));
+	assertType('int|null', $f->doFoo($i));
+};
diff --git a/tests/PHPStan/Rules/Generics/FunctionTemplateTypeRuleTest.php b/tests/PHPStan/Rules/Generics/FunctionTemplateTypeRuleTest.php
@@ -43,6 +43,10 @@ public function testRule(): void
 				'PHPDoc tag @template T for function FunctionTemplateType\resourceBound() with bound type resource is not supported.',
 				50,
 			],
+			[
+				'PHPDoc tag @template T for function FunctionTemplateType\nullNotSupported() with bound type null is not supported.',
+				68,
+			],
 		]);
 	}
 

diff --git a/tests/PHPStan/Rules/Generics/data/function-template.php b/tests/PHPStan/Rules/Generics/data/function-template.php
@@ -63,3 +63,15 @@ function nakano()
 {
 
 }
+
+/** @template T of null */
+function nullNotSupported()
+{
+
+}
+
+/** @template T of ?int */
+function nullableUnionSupported()
+{
+
+}