RemoveNeverUsedMockPropertyRector.php

<?php

declare(strict_types=1);

namespace Rector\PHPUnit\CodeQuality\Rector\Class_;

use PhpParser\Node;
use PhpParser\Node\Expr\Assign;
use PhpParser\Node\Expr\MethodCall;
use PhpParser\Node\Expr\PropertyFetch;
use PhpParser\Node\Stmt\Class_;
use PhpParser\Node\Stmt\ClassMethod;
use PhpParser\Node\Stmt\Expression;
use PhpParser\Node\Stmt\Property;
use Rector\PHPUnit\CodeQuality\NodeAnalyser\MockObjectExprDetector;
use Rector\PHPUnit\CodeQuality\NodeAnalyser\MockObjectPropertyDetector;
use Rector\PHPUnit\NodeAnalyzer\TestsNodeAnalyzer;
use Rector\Rector\AbstractRector;
use Rector\ValueObject\MethodName;
use Symplify\RuleDocGenerator\ValueObject\CodeSample\CodeSample;
use Symplify\RuleDocGenerator\ValueObject\RuleDefinition;

/**
 * @see \Rector\PHPUnit\Tests\CodeQuality\Rector\Class_\RemoveNeverUsedMockPropertyRector\RemoveNeverUsedMockPropertyRectorTest
 */
final class RemoveNeverUsedMockPropertyRector extends AbstractRector
{
    public function __construct(
        private readonly TestsNodeAnalyzer $testsNodeAnalyzer,
        private readonly MockObjectPropertyDetector $mockObjectPropertyDetector,
        private readonly MockObjectExprDetector $mockObjectExprDetector,
    ) {
    }

    public function getRuleDefinition(): RuleDefinition
    {
        return new RuleDefinition(
            'Remove never used property mock, only to set expectations',
            [
                new CodeSample(
                    <<<'CODE_SAMPLE'
use PHPUnit\Framework\TestCase;

final class SomeTest extends TestCase
{
    private $mockProperty = null;

    protected function setUp(): void
    {
        $this->mockProperty = $this->createMock(SomeClass::class);
        $this->mockProperty->expects($this->once())
            ->method('someMethod')
            ->willReturn('someValue');
    }
}
CODE_SAMPLE

                    ,
                    <<<'CODE_SAMPLE'
use PHPUnit\Framework\TestCase;

final class SomeTest extends TestCase
{
    protected function setUp(): void
    {
    }
}
CODE_SAMPLE
                ),
            ]
        );
    }

    /**
     * @return array<class-string<Node>>
     */
    public function getNodeTypes(): array
    {
        return [Class_::class];
    }

    /**
     * @param Class_ $node
     */
    public function refactor(Node $node): ?Node
    {
        if (! $this->testsNodeAnalyzer->isInTestClass($node)) {
            return null;
        }

        $setUpClassMethod = $node->getMethod(MethodName::SET_UP);
        if (! $setUpClassMethod instanceof ClassMethod) {
            return null;
        }

        $propertyNamesToCreateMockMethodCalls = $this->mockObjectPropertyDetector->collectFromClassMethod(
            $setUpClassMethod
        );
        if ($propertyNamesToCreateMockMethodCalls === []) {
            return null;
        }

        $propertyNamesToRemove = [];
        foreach (array_keys($propertyNamesToCreateMockMethodCalls) as $propertyName) {
            if ($this->mockObjectExprDetector->isPropertyMockObjectPassedAsArgument($node, $propertyName)) {
                continue;
            }

            $propertyNamesToRemove[] = $propertyName;
        }

        if ($propertyNamesToRemove === []) {
            return null;
        }

        // remove never used mock properties
        foreach ($propertyNamesToRemove as $propertyNameToRemove) {
            // 1. remove property
            $this->removePropertyFromClass($node, $propertyNameToRemove);

            // 2. remove assign from setUp()
            $this->removeMockPropertyFromSetUpMethod($setUpClassMethod, $propertyNameToRemove);

            // 3. remove expression method calls on this property
            foreach ($node->getMethods() as $classMethod) {
                foreach ((array) $classMethod->stmts as $key => $classMethodStmt) {
                    if (! $classMethodStmt instanceof Expression) {
                        continue;
                    }

                    if (! $classMethodStmt->expr instanceof MethodCall) {
                        continue;
                    }

                    $methodCall = $classMethodStmt->expr;
                    $currentMethodCall = $methodCall;
                    while ($currentMethodCall->var instanceof MethodCall) {
                        $currentMethodCall = $currentMethodCall->var;
                    }

                    if (! $currentMethodCall->var instanceof PropertyFetch) {
                        continue;
                    }

                    $propertyFetch = $currentMethodCall->var;
                    if (! $this->isName($propertyFetch->name, $propertyNameToRemove)) {
                        continue;
                    }

                    unset($classMethod->stmts[$key]);
                }
            }
        }

        return $node;
    }

    private function removeMockPropertyFromSetUpMethod(ClassMethod $setUpClassMethod, string $propertyName): void
    {
        foreach ((array) $setUpClassMethod->stmts as $key => $classStmt) {
            if (! $classStmt instanceof Expression) {
                continue;
            }

            if (! $classStmt->expr instanceof Assign) {
                continue;
            }

            $assign = $classStmt->expr;
            if (! $assign->var instanceof PropertyFetch) {
                continue;
            }

            $assignedPropertyFetch = $assign->var;
            if (! $this->isName($assignedPropertyFetch->name, $propertyName)) {
                continue;
            }

            unset($setUpClassMethod->stmts[$key]);
            return;
        }
    }

    private function removePropertyFromClass(Class_ $class, string $propertyNameToRemove): void
    {
        foreach ($class->stmts as $key => $stmt) {
            if (! $stmt instanceof Property) {
                continue;
            }

            if (! $this->isName($stmt, $propertyNameToRemove)) {
                continue;
            }

            unset($class->stmts[$key]);
        }
    }
}