Closes #3676

Author: sebastianbergmann

ChangeLog-13.1.md

@@ -4,6 +4,10 @@ All notable changes of the PHPUnit 13.1 release series are documented in this fi
 
 ## [13.1.1] - 2026-MM-DD
 
+### Changed
+
+* [#3676](https://github.com/sebastianbergmann/phpunit/issues/3676): Include class/interface name in mock object expectation failure messages
+
 ### Fixed
 
 * [#6019](https://github.com/sebastianbergmann/phpunit/issues/6019): `--migrate-configuration` does not update schema location when XML content already validates against current schema

src/Framework/MockObject/Generator/Generator.php

@@ -109,6 +109,7 @@ public function testDouble(string $type, bool $mockObject, ?array $methods = [],
 
         $object = $this->instantiate(
             $mock,
+            $type,
             $callOriginalConstructor,
             $arguments,
             $returnValueGeneration,
@@ -288,7 +289,7 @@ private function userDefinedInterfaceMethods(string $interfaceName): array
      * @throws ReflectionException
      * @throws RuntimeException
      */
-    private function instantiate(DoubledClass $mockClass, bool $callOriginalConstructor, array $arguments, bool $returnValueGeneration, bool $isMockObject): object
+    private function instantiate(DoubledClass $mockClass, string $type, bool $callOriginalConstructor, array $arguments, bool $returnValueGeneration, bool $isMockObject): object
     {
         $className = $mockClass->generate();
 
@@ -311,7 +312,7 @@ private function instantiate(DoubledClass $mockClass, bool $callOriginalConstruc
          */
         $reflector->getProperty('__phpunit_state')->setValue(
             $object,
-            new TestDoubleState($mockClass->configurableMethods(), $returnValueGeneration, $isMockObject),
+            new TestDoubleState($mockClass->configurableMethods(), $type, $returnValueGeneration, $isMockObject),
         );
 
         if ($callOriginalConstructor && $reflector->getConstructor() !== null) {

src/Framework/MockObject/Runtime/Api/StubApi.php

@@ -20,7 +20,7 @@ trait StubApi
 
     public function __phpunit_state(): TestDoubleState
     {
-        return $this->__phpunit_state ?? new TestDoubleState([], true, false);
+        return $this->__phpunit_state ?? new TestDoubleState([], static::class, true, false);
     }
 
     public function __phpunit_getInvocationHandler(): InvocationHandler

src/Framework/MockObject/Runtime/Api/TestDoubleState.php

@@ -20,16 +20,23 @@ final class TestDoubleState
      * @var list<ConfigurableMethod>
      */
     private readonly array $configurableMethods;
+
+    /**
+     * @var class-string
+     */
+    private readonly string $className;
     private readonly bool $generateReturnValues;
     private readonly bool $isMockObject;
     private ?InvocationHandler $invocationHandler = null;
 
     /**
      * @param list<ConfigurableMethod> $configurableMethods
+     * @param class-string             $className
      */
-    public function __construct(array $configurableMethods, bool $generateReturnValues, bool $isMockObject = false)
+    public function __construct(array $configurableMethods, string $className, bool $generateReturnValues, bool $isMockObject = false)
     {
         $this->configurableMethods  = $configurableMethods;
+        $this->className            = $className;
         $this->generateReturnValues = $generateReturnValues;
         $this->isMockObject         = $isMockObject;
     }
@@ -42,6 +49,7 @@ public function invocationHandler(): InvocationHandler
 
         $this->invocationHandler = new InvocationHandler(
             $this->configurableMethods,
+            $this->className,
             $this->generateReturnValues,
             $this->isMockObject,
         );

src/Framework/MockObject/Runtime/InvocationHandler.php

@@ -42,17 +42,24 @@ final class InvocationHandler
      * @var list<ConfigurableMethod>
      */
     private readonly array $configurableMethods;
+
+    /**
+     * @var class-string
+     */
+    private readonly string $className;
     private readonly bool $returnValueGeneration;
     private readonly bool $isMockObject;
     private bool $sealed                            = false;
     private ?AssertionFailedError $assertionFailure = null;
 
     /**
      * @param list<ConfigurableMethod> $configurableMethods
+     * @param class-string             $className
      */
-    public function __construct(array $configurableMethods, bool $returnValueGeneration, bool $isMockObject = false)
+    public function __construct(array $configurableMethods, string $className, bool $returnValueGeneration, bool $isMockObject = false)
     {
         $this->configurableMethods   = $configurableMethods;
+        $this->className             = $className;
         $this->returnValueGeneration = $returnValueGeneration;
         $this->isMockObject          = $isMockObject;
     }
@@ -114,7 +121,7 @@ public function expects(InvocationOrder $rule): InvocationMocker|InvocationStubb
             throw new TestDoubleSealedException;
         }
 
-        $matcher = new Matcher($rule);
+        $matcher = new Matcher($rule, $this->className);
         $this->addMatcher($matcher);
 
         if ($this->isMockObject) {
@@ -210,7 +217,7 @@ public function seal(bool $isMockObject): void
 
         foreach ($this->configurableMethods as $method) {
             if (!in_array($method->name(), $configuredMethods, true)) {
-                $matcher = new Matcher(new InvokedCount(0));
+                $matcher = new Matcher(new InvokedCount(0), $this->className);
 
                 $matcher->setMethodNameRule(new MethodName($method->name()));
 

src/Framework/MockObject/Runtime/Matcher.php

@@ -30,6 +30,11 @@ final class Matcher
 {
     private readonly InvocationOrder $invocationRule;
 
+    /**
+     * @var class-string
+     */
+    private readonly string $className;
+
     /**
      * @var ?non-empty-string
      */
@@ -38,9 +43,13 @@ final class Matcher
     private ?ParametersRule $parametersRule = null;
     private ?Stub $stub                     = null;
 
-    public function __construct(InvocationOrder $rule)
+    /**
+     * @param class-string $className
+     */
+    public function __construct(InvocationOrder $rule, string $className)
     {
         $this->invocationRule = $rule;
+        $this->className      = $className;
     }
 
     public function hasInvocationCountRule(): bool
@@ -130,7 +139,7 @@ public function invoked(Invocation $invocation): mixed
             throw new ExpectationFailedException(
                 sprintf(
                     "Expectation for %s failed.\n%s",
-                    $this->methodNameRule->failureDescription(),
+                    $this->methodNameRule->failureDescription($this->className),
                     $e->getMessage(),
                 ),
                 $e->getComparisonFailure(),
@@ -182,7 +191,7 @@ public function matches(Invocation $invocation): bool
             throw new ExpectationFailedException(
                 sprintf(
                     "Expectation for %s failed.\n%s",
-                    $this->methodNameRule->failureDescription(),
+                    $this->methodNameRule->failureDescription($this->className),
                     $e->getMessage(),
                 ),
                 $e->getComparisonFailure(),
@@ -221,7 +230,7 @@ public function verify(): void
             throw new ExpectationFailedException(
                 sprintf(
                     '%s was expected to be %s but was %s.',
-                    $this->methodNameRule->failureDescription(),
+                    $this->methodNameRule->failureDescription($this->className),
                     $this->invocationRule->toString(),
                     $invoked,
                 ),
@@ -243,7 +252,7 @@ public function verify(): void
                 throw new ExpectationFailedException(
                     sprintf(
                         "Expectation for %s failed.\n%s",
-                        $this->methodNameRule->failureDescription(),
+                        $this->methodNameRule->failureDescription($this->className),
                         ThrowableToStringMapper::map($e),
                     ),
                 );

src/Framework/MockObject/Runtime/ReturnValueGenerator.php

@@ -183,6 +183,7 @@ private function newInstanceOf(StubInternal $testStub, string $className, string
                 $object,
                 new TestDoubleState(
                     $testStub->__phpunit_state()->configurableMethods(),
+                    $className,
                     $testStub->__phpunit_state()->generateReturnValues(),
                 ),
             );

src/Framework/MockObject/Runtime/Rule/MethodName.php

@@ -42,10 +42,13 @@ public function toString(): string
         return 'method name ' . $this->constraint->toString();
     }
 
-    public function failureDescription(): string
+    /**
+     * @param class-string $className
+     */
+    public function failureDescription(string $className): string
     {
         if ($this->constraint instanceof MethodNameConstraint) {
-            return '"' . $this->constraint->methodName() . '()"';
+            return $className . '::' . $this->constraint->methodName() . '()';
         }
 
         return $this->toString();

tests/end-to-end/event/failed-mock-expectation.phpt

@@ -23,7 +23,7 @@ Test Preparation Started (PHPUnit\TestFixture\Event\FailedExpectationTest::testO
 Test Prepared (PHPUnit\TestFixture\Event\FailedExpectationTest::testOne)
 Mock Object Created (PHPUnit\TestFixture\MockObject\AnInterface)
 Test Failed (PHPUnit\TestFixture\Event\FailedExpectationTest::testOne)
-"doSomething()" was expected to be invoked once but was never invoked.
+PHPUnit\TestFixture\MockObject\AnInterface::doSomething() was expected to be invoked once but was never invoked.
 Test Finished (PHPUnit\TestFixture\Event\FailedExpectationTest::testOne)
 Test Suite Finished (PHPUnit\TestFixture\Event\FailedExpectationTest, 1 test)
 Test Runner Execution Finished

tests/end-to-end/regression/6138.phpt

@@ -21,7 +21,7 @@ Time: %s, Memory: %s
 There was 1 failure:
 
 1) PHPUnit\TestFixture\Issue6138\Issue6138Test::testOne
-Expectation for "m()" failed.
+Expectation for PHPUnit\TestFixture\Issue6138\I::m() failed.
 Parameter $c for invocation PHPUnit\TestFixture\Issue6138\I::m(PHPUnit\TestFixture\Issue6138\C Object (...)): void does not match expected value.
 Failed asserting that two objects are equal.
 --- Expected