GetTemplateTypeRule

Author: ondrejmirtes

Diff for: conf/config.level0.neon

@@ -31,6 +31,7 @@ rules:
 	- PHPStan\Rules\Api\ApiMethodCallRule
 	- PHPStan\Rules\Api\ApiStaticCallRule
 	- PHPStan\Rules\Api\ApiTraitUseRule
+	- PHPStan\Rules\Api\GetTemplateTypeRule
 	- PHPStan\Rules\Api\PhpStanNamespaceIn3rdPartyPackageRule
 	- PHPStan\Rules\Arrays\DuplicateKeysInLiteralArraysRule
 	- PHPStan\Rules\Arrays\EmptyArrayItemRule

Diff for: src/Rules/Api/GetTemplateTypeRule.php

@@ -0,0 +1,81 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Api;
+
+use PhpParser\Node;
+use PhpParser\Node\Expr\MethodCall;
+use PHPStan\Analyser\Scope;
+use PHPStan\Reflection\ReflectionProvider;
+use PHPStan\Rules\Rule;
+use PHPStan\Rules\RuleErrorBuilder;
+use PHPStan\Type\Type;
+use function count;
+use function sprintf;
+
+/**
+ * @implements Rule<MethodCall>
+ */
+class GetTemplateTypeRule implements Rule
+{
+
+	public function __construct(private ReflectionProvider $reflectionProvider)
+	{
+	}
+
+	public function getNodeType(): string
+	{
+		return MethodCall::class;
+	}
+
+	public function processNode(Node $node, Scope $scope): array
+	{
+		$args = $node->getArgs();
+		if (count($args) < 2) {
+			return [];
+		}
+		if (!$node->name instanceof Node\Identifier) {
+			return [];
+		}
+
+		if ($node->name->toLowerString() !== 'gettemplatetype') {
+			return [];
+		}
+
+		$calledOnType = $scope->getType($node->var);
+		$methodReflection = $scope->getMethodReflection($calledOnType, $node->name->toString());
+		if ($methodReflection === null) {
+			return [];
+		}
+
+		if (!$methodReflection->getDeclaringClass()->is(Type::class)) {
+			return [];
+		}
+
+		$classType = $scope->getType($args[0]->value);
+		$templateType = $scope->getType($args[1]->value);
+		$errors = [];
+		foreach ($classType->getConstantStrings() as $classNameType) {
+			if (!$this->reflectionProvider->hasClass($classNameType->getValue())) {
+				continue;
+			}
+			$classReflection = $this->reflectionProvider->getClass($classNameType->getValue());
+			$templateTypeMap = $classReflection->getTemplateTypeMap();
+			foreach ($templateType->getConstantStrings() as $templateTypeName) {
+				if ($templateTypeMap->hasType($templateTypeName->getValue())) {
+					continue;
+				}
+
+				$errors[] = RuleErrorBuilder::message(sprintf(
+					'Call to %s::%s() references unknown template type %s on class %s.',
+					$methodReflection->getDeclaringClass()->getDisplayName(),
+					$methodReflection->getName(),
+					$templateTypeName->getValue(),
+					$classReflection->getDisplayName(),
+				))->build();
+			}
+		}
+
+		return $errors;
+	}
+
+}

Diff for: tests/PHPStan/Rules/Api/GetTemplateTypeRuleTest.php

@@ -0,0 +1,33 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Api;
+
+use PHPStan\Rules\Rule;
+use PHPStan\Testing\RuleTestCase;
+
+/**
+ * @extends RuleTestCase<GetTemplateTypeRule>
+ */
+class GetTemplateTypeRuleTest extends RuleTestCase
+{
+
+	protected function getRule(): Rule
+	{
+		return new GetTemplateTypeRule($this->createReflectionProvider());
+	}
+
+	public function testRule(): void
+	{
+		$this->analyse([__DIR__ . '/data/get-template-type.php'], [
+			[
+				'Call to PHPStan\Type\Type::getTemplateType() references unknown template type TSendd on class Generator.',
+				15,
+			],
+			[
+				'Call to PHPStan\Type\ObjectType::getTemplateType() references unknown template type TSendd on class Generator.',
+				21,
+			],
+		]);
+	}
+
+}

Diff for: tests/PHPStan/Rules/Api/data/get-template-type.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace GetTemplateType;
+
+use Generator;
+use PHPStan\Type\ObjectType;
+use PHPStan\Type\Type;
+
+class Foo
+{
+
+	public function doFoo(Type $type): void
+	{
+		$type->getTemplateType(Generator::class, 'TSend');
+		$type->getTemplateType(Generator::class, 'TSendd');
+	}
+
+	public function doBar(ObjectType $type): void
+	{
+		$type->getTemplateType(Generator::class, 'TSend');
+		$type->getTemplateType(Generator::class, 'TSendd');
+	}
+
+}