Merge pull request #1261 from rectorphp/dead-if-foreach-for

[DeadCode] Add RemoveDeadIfForeachForRector

config/level/dead-code/dead-code.yaml

@@ -14,3 +14,4 @@ services:
     Rector\DeadCode\Rector\FunctionLike\RemoveCodeAfterReturnRector: ~
     Rector\DeadCode\Rector\ClassMethod\RemoveDeadConstructorRector: ~
     Rector\DeadCode\Rector\FunctionLike\RemoveDeadReturnRector: ~
+    Rector\DeadCode\Rector\For_\RemoveDeadIfForeachForRector: ~

packages/DeadCode/src/Rector/For_/RemoveDeadIfForeachForRector.php

@@ -0,0 +1,147 @@
+<?php declare(strict_types=1);
+
+namespace Rector\DeadCode\Rector\For_;
+
+use PhpParser\Node;
+use PhpParser\Node\Expr;
+use PhpParser\Node\Expr\Variable;
+use PhpParser\Node\Scalar;
+use PhpParser\Node\Stmt\For_;
+use PhpParser\Node\Stmt\Foreach_;
+use PhpParser\Node\Stmt\If_;
+use Rector\Rector\AbstractRector;
+use Rector\RectorDefinition\CodeSample;
+use Rector\RectorDefinition\RectorDefinition;
+
+final class RemoveDeadIfForeachForRector extends AbstractRector
+{
+    public function getDefinition(): RectorDefinition
+    {
+        return new RectorDefinition('Remove if, foreach and for that does not do anything', [
+            new CodeSample(
+                <<<'CODE_SAMPLE'
+class SomeClass
+{
+    public function run($someObject)
+    {
+        $value = 5;
+        if ($value) {
+        }
+
+        if ($someObject->run()) {
+        }
+
+        foreach ($values as $value) {
+        }
+
+        return $value;
+    }
+}
+CODE_SAMPLE
+                ,
+                <<<'CODE_SAMPLE'
+class SomeClass
+{
+    public function run($someObject)
+    {
+        $value = 5;
+        if ($someObject->run()) {
+        }
+
+        return $value;
+    }
+}
+CODE_SAMPLE
+            ),
+        ]);
+    }
+
+    /**
+     * @return string[]
+     */
+    public function getNodeTypes(): array
+    {
+        return [For_::class, If_::class, Foreach_::class];
+    }
+
+    /**
+     * @param For_|If_|Foreach_ $node
+     */
+    public function refactor(Node $node): ?Node
+    {
+        if ($node instanceof If_) {
+            return $this->processIf($node);
+        }
+
+        if ($node instanceof Foreach_) {
+            return $this->processForeach($node);
+        }
+
+        if ($node instanceof For_) {
+            if ($node->stmts) {
+                return null;
+            }
+
+            $this->removeNode($node);
+
+            return null;
+        }
+
+        return $node;
+    }
+
+    private function processIf(If_ $if): ?If_
+    {
+        if ($if->stmts) {
+            return null;
+        }
+
+        if ($if->else) {
+            return null;
+        }
+
+        if ($if->elseifs) {
+            return null;
+        }
+
+        if ($this->isNodeWithSideEffect($if->cond)) {
+            return null;
+        }
+
+        $this->removeNode($if);
+
+        return null;
+    }
+
+    private function processForeach(Foreach_ $node): ?Foreach_
+    {
+        if ($node->stmts) {
+            return null;
+        }
+
+        if ($this->isNodeWithSideEffect($node->expr)) {
+            return null;
+        }
+
+        $this->removeNode($node);
+
+        return null;
+    }
+
+    private function isNodeWithSideEffect(Expr $expr): bool
+    {
+        if ($expr instanceof Variable) {
+            return false;
+        }
+
+        if ($expr instanceof Scalar) {
+            return false;
+        }
+
+        if ($this->isBool($expr)) {
+            return false;
+        }
+
+        return true;
+    }
+}

packages/DeadCode/tests/Rector/For_/RemoveDeadIfForeachForRector/Fixture/fixture.php.inc

@@ -0,0 +1,55 @@
+<?php
+
+namespace Rector\DeadCode\Tests\Rector\For_\RemoveDeadIfForeachForRector\Fixture;
+
+class SomeClass
+{
+    public function run($someObject)
+    {
+        $value = 5;
+        if ($value) {
+        }
+
+        if ($someObject->run()) {
+        }
+
+        $values = [];
+        foreach ($values as $value) {
+        }
+
+        return $value;
+    }
+
+    public function forMe()
+    {
+        for ($i = 0; $i < 5; ++$i) {
+        }
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\DeadCode\Tests\Rector\For_\RemoveDeadIfForeachForRector\Fixture;
+
+class SomeClass
+{
+    public function run($someObject)
+    {
+        $value = 5;
+
+        if ($someObject->run()) {
+        }
+
+        $values = [];
+
+        return $value;
+    }
+
+    public function forMe()
+    {
+    }
+}
+
+?>

packages/DeadCode/tests/Rector/For_/RemoveDeadIfForeachForRector/Fixture/side_effect_checks.php.inc

@@ -0,0 +1,35 @@
+<?php
+
+namespace Rector\DeadCode\Tests\Rector\For_\RemoveDeadIfForeachForRector\Fixture;
+
+class SideEffectChecks
+{
+    public function run()
+    {
+        if (10) {
+        }
+
+        if (true) {
+        }
+
+        if (5 + 10) {
+        }
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\DeadCode\Tests\Rector\For_\RemoveDeadIfForeachForRector\Fixture;
+
+class SideEffectChecks
+{
+    public function run()
+    {
+        if (5 + 10) {
+        }
+    }
+}
+
+?>

packages/DeadCode/tests/Rector/For_/RemoveDeadIfForeachForRector/RemoveDeadIfForeachForRectorTest.php

@@ -0,0 +1,22 @@
+<?php declare(strict_types=1);
+
+namespace Rector\DeadCode\Tests\Rector\For_\RemoveDeadIfForeachForRector;
+
+use Rector\DeadCode\Rector\For_\RemoveDeadIfForeachForRector;
+use Rector\Testing\PHPUnit\AbstractRectorTestCase;
+
+final class RemoveDeadIfForeachForRectorTest extends AbstractRectorTestCase
+{
+    public function test(): void
+    {
+        $this->doTestFiles([
+            __DIR__ . '/Fixture/fixture.php.inc',
+            __DIR__ . '/Fixture/side_effect_checks.php.inc',
+        ]);
+    }
+
+    protected function getRectorClass(): string
+    {
+        return RemoveDeadIfForeachForRector::class;
+    }
+}

packages/Php/tests/Rector/FuncCall/RegexDashEscapeRector/Fixture/variable.php.inc

@@ -2,7 +2,7 @@
 
 namespace Rector\Php\Tests\Rector\FuncCall\RegexDashEscapeRector\Fixture;
 
-class Variable
+class RegexInAVar
 {
     public function run()
     {
@@ -20,7 +20,7 @@ class Variable
 
 namespace Rector\Php\Tests\Rector\FuncCall\RegexDashEscapeRector\Fixture;
 
-class Variable
+class RegexInAVar
 {
     public function run()
     {