Regression test

Author: ondrejmirtes

tests/PHPStan/Analyser/AnalyserIntegrationTest.php

@@ -721,6 +721,13 @@ public function testBug7068(): void
 		$this->assertNoErrors($errors);
 	}
 
+	public function testDiscussion6993(): void
+	{
+		$errors = $this->runAnalyse(__DIR__ . '/data/bug-6993.php');
+		$this->assertCount(1, $errors);
+		$this->assertSame('Parameter #1 $specificable of method Bug6993\AndSpecificationValidator<Bug6993\TestSpecification,Bug6993\Foo>::isSatisfiedBy() expects Bug6993\Foo, Bug6993\Bar given.', $errors[0]->getMessage());
+	}
+
 	/**
 	 * @param string[]|null $allAnalysedFiles
 	 * @return Error[]

tests/PHPStan/Analyser/NodeScopeResolverTest.php

@@ -882,6 +882,7 @@ public function dataFileAsserts(): iterable
 		require_once __DIR__ . '/data/constant-phpdoc-type.php';
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/constant-phpdoc-type.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-7068.php');
+		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-6993.php');
 	}
 
 	/**

tests/PHPStan/Analyser/data/bug-6993.php

@@ -0,0 +1,82 @@
+<?php
+
+namespace Bug6993;
+
+use function PHPStan\Testing\assertType;
+
+/**
+ * @template T
+ *
+ * Generic specification interface
+ */
+interface SpecificationInterface {
+	/**
+	 * @param T $specificable
+	 */
+	public function isSatisfiedBy($specificable): bool;
+}
+
+/**
+ * @template-extends SpecificationInterface<Foo>
+ */
+interface FooSpecificationInterface extends SpecificationInterface
+{
+}
+
+/**
+ * Class-conctrete specification
+ */
+class TestSpecification implements FooSpecificationInterface
+{
+	public function isSatisfiedBy($specificable): bool
+	{
+		return true;
+	}
+}
+
+/**
+ * @template TSpecifications of SpecificationInterface<TValue>
+ * @template TValue
+ * @template-implements SpecificationInterface<TValue>
+ */
+class AndSpecificationValidator implements SpecificationInterface
+{
+	/**
+	 * @param array<TSpecifications> $specifications
+	 */
+	public function __construct(private array $specifications)
+	{
+	}
+
+	public function isSatisfiedBy($specificable): bool
+	{
+		foreach ($this->specifications as $specification) {
+			if (!$specification->isSatisfiedBy($specificable)) {
+				return false;
+			}
+		}
+
+		return true;
+	}
+}
+
+/**
+ * Admitted value for FooSpecificationInterface instances
+ */
+class Foo
+{
+}
+
+/**
+ * Value not admitted for FooSpecificationInterface instances
+ */
+class Bar
+{
+}
+
+function (): void {
+	$and = (new AndSpecificationValidator([new TestSpecification()]));
+	assertType('Bug6993\AndSpecificationValidator<Bug6993\TestSpecification, Bug6993\Foo>', $and);
+	$and->isSatisfiedBy(new Foo());
+	$and->isSatisfiedBy(new Bar());
+};