Report error when trying to configure a non existing method on MockObject

Author: VincentLanglet

extension.neon

@@ -5,6 +5,7 @@ parameters:
 - markTestIncomplete
 - markTestSkipped
 stubFiles:
+- stubs/InvocationMocker.stub
 - stubs/MockBuilder.stub
 - stubs/MockObject.stub
 - stubs/TestCase.stub
@@ -26,7 +27,15 @@ services:
 class: PHPStan\Type\PHPUnit\Assert\AssertStaticMethodTypeSpecifyingExtension
 tags:
 - phpstan.typeSpecifier.staticMethodTypeSpecifyingExtension
+-
+class: PHPStan\Type\PHPUnit\InvocationMockerDynamicReturnTypeExtension
+tags:
+- phpstan.broker.dynamicMethodReturnTypeExtension
 -
 class: PHPStan\Type\PHPUnit\MockBuilderDynamicReturnTypeExtension
 tags:
 - phpstan.broker.dynamicMethodReturnTypeExtension
+-
+class: PHPStan\Type\PHPUnit\MockObjectDynamicReturnTypeExtension
+tags:
+- phpstan.broker.dynamicMethodReturnTypeExtension

rules.neon

@@ -2,3 +2,4 @@ rules:
 - PHPStan\Rules\PHPUnit\AssertSameBooleanExpectedRule
 - PHPStan\Rules\PHPUnit\AssertSameNullExpectedRule
 - PHPStan\Rules\PHPUnit\AssertSameWithCountRule
+- PHPStan\Rules\PHPUnit\MockMethodCallRule

src/Rules/PHPUnit/MockMethodCallRule.php

@@ -0,0 +1,85 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\PHPUnit;
+
+use PhpParser\Node;
+use PHPStan\Analyser\Scope;
+use PHPStan\Type\Constant\ConstantStringType;
+use PHPStan\Type\Generic\GenericObjectType;
+use PHPStan\Type\IntersectionType;
+use PHPStan\Type\ObjectType;
+use PHPUnit\Framework\MockObject\InvocationMocker;
+use PHPUnit\Framework\MockObject\MockObject;
+
+/**
+ * @implements \PHPStan\Rules\Rule<\PhpParser\Node\Expr\MethodCall>
+ */
+class MockMethodCallRule implements \PHPStan\Rules\Rule
+{
+
+public function getNodeType(): string
+{
+return Node\Expr\MethodCall::class;
+}
+
+public function processNode(Node $node, Scope $scope): array
+{
+/** @var Node\Expr\MethodCall $node */
+$node = $node;
+
+if (!$node->name instanceof Node\Identifier || $node->name->name !== 'method') {
+return [];
+}
+
+if (count($node->args) < 1) {
+return [];
+}
+
+$argType = $scope->getType($node->args[0]->value);
+if (!($argType instanceof ConstantStringType)) {
+return [];
+}
+
+$method = $argType->getValue();
+$type = $scope->getType($node->var);
+
+if (
+$type instanceof IntersectionType
+&& in_array(MockObject::class, $type->getReferencedClasses(), true)
+&& !$type->hasMethod($method)->yes()
+) {
+$mockClass = array_filter($type->getReferencedClasses(), function (string $class): bool {
+return $class !== MockObject::class;
+});
+
+return [
+sprintf(
+'Trying to mock an undefined method %s() on class %s.',
+$method,
+\implode('&', $mockClass)
+),
+];
+}
+
+if (
+$type instanceof GenericObjectType
+&& $type->getClassName() === InvocationMocker::class
+&& count($type->getTypes()) > 0
+) {
+$mockClass = $type->getTypes()[0];
+
+if ($mockClass instanceof ObjectType && !$mockClass->hasMethod($method)->yes()) {
+return [
+sprintf(
+'Trying to mock an undefined method %s() on class %s.',
+$method,
+$mockClass->getClassName()
+),
+];
+}
+}
+
+return [];
+}
+
+}

src/Type/PHPUnit/InvocationMockerDynamicReturnTypeExtension.php

@@ -0,0 +1,29 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Type\PHPUnit;
+
+use PhpParser\Node\Expr\MethodCall;
+use PHPStan\Analyser\Scope;
+use PHPStan\Reflection\MethodReflection;
+use PHPStan\Type\Type;
+use PHPUnit\Framework\MockObject\Builder\InvocationMocker;
+
+class InvocationMockerDynamicReturnTypeExtension implements \PHPStan\Type\DynamicMethodReturnTypeExtension
+{
+
+public function getClass(): string
+{
+return InvocationMocker::class;
+}
+
+public function isMethodSupported(MethodReflection $methodReflection): bool
+{
+return $methodReflection->getName() !== 'getMatcher';
+}
+
+public function getTypeFromMethodCall(MethodReflection $methodReflection, MethodCall $methodCall, Scope $scope): Type
+{
+return $scope->getType($methodCall->var);
+}
+
+}

src/Type/PHPUnit/MockObjectDynamicReturnTypeExtension.php

@@ -0,0 +1,42 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Type\PHPUnit;
+
+use PhpParser\Node\Expr\MethodCall;
+use PHPStan\Analyser\Scope;
+use PHPStan\Reflection\MethodReflection;
+use PHPStan\Type\Generic\GenericObjectType;
+use PHPStan\Type\IntersectionType;
+use PHPStan\Type\Type;
+use PHPStan\Type\TypeWithClassName;
+use PHPUnit\Framework\MockObject\InvocationMocker;
+use PHPUnit\Framework\MockObject\MockObject;
+
+class MockObjectDynamicReturnTypeExtension implements \PHPStan\Type\DynamicMethodReturnTypeExtension
+{
+
+public function getClass(): string
+{
+return MockObject::class;
+}
+
+public function isMethodSupported(MethodReflection $methodReflection): bool
+{
+return $methodReflection->getName() === 'expects';
+}
+
+public function getTypeFromMethodCall(MethodReflection $methodReflection, MethodCall $methodCall, Scope $scope): Type
+{
+$type = $scope->getType($methodCall->var);
+if (!($type instanceof IntersectionType)) {
+return new GenericObjectType(InvocationMocker::class, []);
+}
+
+$mockClasses = array_filter($type->getTypes(), function (Type $type): bool {
+return !$type instanceof TypeWithClassName || $type->getClassName() !== MockObject::class;
+});
+
+return new GenericObjectType(InvocationMocker::class, $mockClasses);
+}
+
+}

stubs/InvocationMocker.stub

@@ -0,0 +1,13 @@
+<?php
+
+namespace PHPUnit\Framework\MockObject\Builder;
+
+use PHPUnit\Framework\MockObject\Stub;
+
+/**
+ * @template TMockedClass
+ */
+class InvocationMocker
+{
+
+}

tests/Rules/PHPUnit/MockMethodCallRuleTest.php

@@ -0,0 +1,42 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\PHPUnit;
+
+use PHPStan\Rules\Rule;
+
+/**
+ * @extends \PHPStan\Testing\RuleTestCase<MockMethodCallRule>
+ */
+class MockMethodCallRuleTest extends \PHPStan\Testing\RuleTestCase
+{
+
+protected function getRule(): Rule
+{
+return new MockMethodCallRule();
+}
+
+public function testRule(): void
+{
+$this->analyse([__DIR__ . '/data/mock-method-call.php'], [
+[
+'Trying to mock an undefined method doBadThing() on class MockMethodCall\Bar.',
+15,
+],
+[
+'Trying to mock an undefined method doBadThing() on class MockMethodCall\Bar.',
+20,
+],
+]);
+}
+
+/**
+ * @return string[]
+ */
+public static function getAdditionalConfigFiles(): array
+{
+return [
+__DIR__ . '/../../../extension.neon',
+];
+}
+
+}

tests/Rules/PHPUnit/data/mock-method-call.php

@@ -0,0 +1,43 @@
+<?php declare(strict_types = 1);
+
+namespace MockMethodCall;
+
+class Foo extends \PHPUnit\Framework\TestCase
+{
+
+public function testGoodMethod()
+{
+$this->createMock(Bar::class)->method('doThing');
+}
+
+public function testBadMethod()
+{
+$this->createMock(Bar::class)->method('doBadThing');
+}
+
+public function testBadMethodWithExpectation()
+{
+$this->createMock(Bar::class)->expects($this->once())->method('doBadThing');
+}
+
+public function testWithAnotherObject()
+{
+$bar = new BarWithMethod();
+$bar->method('doBadThing');
+}
+
+}
+
+class Bar {
+public function doThing()
+{
+return 1;
+}
+};
+
+class BarWithMethod {
+public function method(string $string)
+{
+return $string;
+}
+};