Merge pull request #2948 from rectorphp/dead-if-return

[DeadCode] Add RemoveDuplicatedIfReturnRector

config/set/dead-code/dead-code.yaml

@@ -34,3 +34,4 @@ services:
     Rector\DeadCode\Rector\TryCatch\RemoveDeadTryCatchRector: null
     Rector\DeadCode\Rector\ClassConst\RemoveUnusedClassConstantRector: null
     Rector\DeadCode\Rector\Assign\RemoveUnusedVariableAssignRector: null
+    Rector\DeadCode\Rector\FunctionLike\RemoveDuplicatedIfReturnRector: null

docs/AllRectorsOverview.md

@@ -1,4 +1,4 @@
-# All 463 Rectors Overview
+# All 464 Rectors Overview
 
 - [Projects](#projects)
 - [General](#general)
@@ -2791,6 +2791,33 @@ Remove duplicated key in defined arrays.
 
 <br>
 
+### `RemoveDuplicatedIfReturnRector`
+
+- class: [`Rector\DeadCode\Rector\FunctionLike\RemoveDuplicatedIfReturnRector`](/../master/rules/dead-code/src/Rector/FunctionLike/RemoveDuplicatedIfReturnRector.php)
+- [test fixtures](/../master/rules/dead-code/tests/Rector/FunctionLike/RemoveDuplicatedIfReturnRector/Fixture)
+
+Remove duplicated if stmt with return in function/method body
+
+```diff
+ class SomeClass
+ {
+     public function run($value)
+     {
+         if ($value) {
+             return true;
+         }
+
+         $value2 = 100;
+-
+-        if ($value) {
+-            return true;
+-        }
+     }
+ }
+```
+
+<br>
+
 ### `RemoveDuplicatedInstanceOfRector`
 
 - class: [`Rector\DeadCode\Rector\Instanceof_\RemoveDuplicatedInstanceOfRector`](/../master/rules/dead-code/src/Rector/Instanceof_/RemoveDuplicatedInstanceOfRector.php)

rules/dead-code/src/Rector/FunctionLike/RemoveDuplicatedIfReturnRector.php

@@ -0,0 +1,200 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\DeadCode\Rector\FunctionLike;
+
+use PhpParser\Node;
+use PhpParser\Node\Expr\Assign;
+use PhpParser\Node\Expr\Variable;
+use PhpParser\Node\FunctionLike;
+use PhpParser\Node\Stmt\If_;
+use PhpParser\NodeTraverser;
+use Rector\Core\PhpParser\Node\Manipulator\IfManipulator;
+use Rector\Core\Rector\AbstractRector;
+use Rector\Core\RectorDefinition\CodeSample;
+use Rector\Core\RectorDefinition\RectorDefinition;
+
+/**
+ * @see https://github.com/rectorphp/rector/issues/2945
+ *
+ * @see \Rector\DeadCode\Tests\Rector\FunctionLike\RemoveDuplicatedIfReturnRector\RemoveDuplicatedIfReturnRectorTest
+ */
+final class RemoveDuplicatedIfReturnRector extends AbstractRector
+{
+    /**
+     * @var IfManipulator
+     */
+    private $ifManipulator;
+
+    public function __construct(IfManipulator $ifManipulator)
+    {
+        $this->ifManipulator = $ifManipulator;
+    }
+
+    public function getDefinition(): RectorDefinition
+    {
+        return new RectorDefinition('Remove duplicated if stmt with return in function/method body', [
+            new CodeSample(
+                <<<'PHP'
+class SomeClass
+{
+    public function run($value)
+    {
+        if ($value) {
+            return true;
+        }
+
+        $value2 = 100;
+
+        if ($value) {
+            return true;
+        }
+    }
+}
+PHP
+,
+                <<<'PHP'
+class SomeClass
+{
+    public function run($value)
+    {
+        if ($value) {
+            return true;
+        }
+
+        $value2 = 100;
+    }
+}
+PHP
+
+            ),
+        ]);
+    }
+
+    /**
+     * @return string[]
+     */
+    public function getNodeTypes(): array
+    {
+        return [FunctionLike::class];
+    }
+
+    /**
+     * @param FunctionLike $node
+     */
+    public function refactor(Node $node): ?Node
+    {
+        $ifWithOnlyReturnsByHash = $this->collectDuplicatedIfWithOnlyReturnByHash($node);
+        if ($ifWithOnlyReturnsByHash === []) {
+            return null;
+        }
+
+        foreach ($ifWithOnlyReturnsByHash as $stmts) {
+            // keep first one
+            array_shift($stmts);
+
+            foreach ($stmts as $stmt) {
+                $this->removeNode($stmt);
+            }
+        }
+
+        return $node;
+    }
+
+    /**
+     * @return If_[][]
+     */
+    private function collectDuplicatedIfWithOnlyReturnByHash(FunctionLike $functionLike): array
+    {
+        $ifWithOnlyReturnsByHash = [];
+        $modifiedVariableNames = [];
+
+        foreach ((array) $functionLike->getStmts() as $stmt) {
+            if (! $this->ifManipulator->isIfWithOnlyReturn($stmt)) {
+                // variable modification
+                $modifiedVariableNames += $this->collectModifiedVariableNames($stmt);
+
+                continue;
+            }
+
+            if ($this->containsVariableNames($stmt, $modifiedVariableNames)) {
+                continue;
+            }
+
+            /** @var If_ $stmt */
+            $hash = $this->printWithoutComments($stmt);
+            $ifWithOnlyReturnsByHash[$hash][] = $stmt;
+        }
+
+        return $this->filterOutSingleItemStmts($ifWithOnlyReturnsByHash);
+    }
+
+    /**
+     * @param If_[][] $ifWithOnlyReturnsByHash
+     * @return If_[][]
+     */
+    private function filterOutSingleItemStmts(array $ifWithOnlyReturnsByHash): array
+    {
+        return array_filter($ifWithOnlyReturnsByHash, function (array $stmts) {
+            return count($stmts) >= 2;
+        });
+    }
+
+    /**
+     * @return string[]
+     */
+    private function collectModifiedVariableNames(Node $node): array
+    {
+        $modifiedVariableNames = [];
+
+        $this->traverseNodesWithCallable($node, function (Node $node) use (&$modifiedVariableNames) {
+            if (! $node instanceof Assign) {
+                return null;
+            }
+
+            if (! $node->var instanceof Variable) {
+                return null;
+            }
+
+            $variableName = $this->getName($node->var);
+            if ($variableName === null) {
+                return null;
+            }
+
+            $modifiedVariableNames[] = $variableName;
+        });
+
+        return $modifiedVariableNames;
+    }
+
+    /**
+     * @param string[] $modifiedVariableNames
+     */
+    private function containsVariableNames(Node $node, array $modifiedVariableNames): bool
+    {
+        if ($modifiedVariableNames === []) {
+            return false;
+        }
+
+        $containsVariableNames = false;
+        $this->traverseNodesWithCallable($node, function (Node $node) use (
+            $modifiedVariableNames,
+            &$containsVariableNames
+        ) {
+            if (! $node instanceof Variable) {
+                return null;
+            }
+
+            if (! $this->isNames($node, $modifiedVariableNames)) {
+                return null;
+            }
+
+            $containsVariableNames = true;
+
+            return NodeTraverser::STOP_TRAVERSAL;
+        });
+
+        return $containsVariableNames;
+    }
+}

rules/dead-code/tests/Rector/FunctionLike/RemoveDuplicatedIfReturnRector/Fixture/fixture.php.inc

@@ -0,0 +1,39 @@
+<?php
+
+namespace Rector\DeadCode\Tests\Rector\FunctionLike\RemoveDuplicatedIfReturnRector\Fixture;
+
+class SomeClass
+{
+    public function run($value)
+    {
+        if ($value) {
+            return true;
+        }
+
+        $value2 = 100;
+
+        if ($value) {
+            return true;
+        }
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\DeadCode\Tests\Rector\FunctionLike\RemoveDuplicatedIfReturnRector\Fixture;
+
+class SomeClass
+{
+    public function run($value)
+    {
+        if ($value) {
+            return true;
+        }
+
+        $value2 = 100;
+    }
+}
+
+?>

rules/dead-code/tests/Rector/FunctionLike/RemoveDuplicatedIfReturnRector/Fixture/skip_modified_value.php.inc

@@ -0,0 +1,19 @@
+<?php
+
+namespace Rector\DeadCode\Tests\Rector\FunctionLike\RemoveDuplicatedIfReturnRector\Fixture;
+
+class SkipModifiedValue
+{
+    public function run()
+    {
+        $value = random_int(1, 5);
+        if ($value) {
+            return true;
+        }
+
+        $value = random_int(1, 5);
+        if ($value) {
+            return true;
+        }
+    }
+}

rules/dead-code/tests/Rector/FunctionLike/RemoveDuplicatedIfReturnRector/Fixture/skip_this.php.inc

@@ -0,0 +1,19 @@
+<?php
+
+namespace Rector\DeadCode\Tests\Rector\FunctionLike\RemoveDuplicatedIfReturnRector\Fixture;
+
+class SkipThis
+{
+    public function run($value)
+    {
+        if ($value) {
+            return true;
+        }
+
+        $value2 = 100;
+
+        if ($value2) {
+            return true;
+        }
+    }
+}

rules/dead-code/tests/Rector/FunctionLike/RemoveDuplicatedIfReturnRector/Fixture/skip_with_differnt_value.php.inc

@@ -0,0 +1,19 @@
+<?php
+
+namespace Rector\DeadCode\Tests\Rector\FunctionLike\RemoveDuplicatedIfReturnRector\Fixture;
+
+class SkipWithDifferentValue
+{
+    public function run($value)
+    {
+        // is yml/yaml file
+        if (Strings::match($possibleFileNodeAsString, '#\.(yml|yaml)(\'|")$#')) {
+            return true;
+        }
+
+        // is probably a file variable
+        if (Strings::match($possibleFileNodeAsString, '#\File$#')) {
+            return true;
+        }
+    }
+}

rules/dead-code/tests/Rector/FunctionLike/RemoveDuplicatedIfReturnRector/RemoveDuplicatedIfReturnRectorTest.php

@@ -0,0 +1,30 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\DeadCode\Tests\Rector\FunctionLike\RemoveDuplicatedIfReturnRector;
+
+use Iterator;
+use Rector\Core\Testing\PHPUnit\AbstractRectorTestCase;
+use Rector\DeadCode\Rector\FunctionLike\RemoveDuplicatedIfReturnRector;
+
+final class RemoveDuplicatedIfReturnRectorTest extends AbstractRectorTestCase
+{
+    /**
+     * @dataProvider provideData()
+     */
+    public function test(string $file): void
+    {
+        $this->doTestFile($file);
+    }
+
+    public function provideData(): Iterator
+    {
+        return $this->yieldFilesFromDirectory(__DIR__ . '/Fixture');
+    }
+
+    protected function getRectorClass(): string
+    {
+        return RemoveDuplicatedIfReturnRector::class;
+    }
+}

src/PhpParser/Node/Manipulator/IfManipulator.php

@@ -263,6 +263,19 @@ final class IfManipulator
         return $ifs;
     }
 
+    public function isIfWithOnlyReturn(Node $node): bool
+    {
+        if (! $node instanceof If_) {
+            return false;
+        }
+
+        if (! $this->isIfWithoutElseAndElseIfs($node)) {
+            return false;
+        }
+
+        return $this->hasOnlyStmtOfType($node, Return_::class);
+    }
+
     private function matchComparedAndReturnedNode(NotIdentical $notIdentical, Return_ $returnNode): ?Expr
     {
         if ($this->betterStandardPrinter->areNodesEqual(

src/PhpParser/Printer/BetterStandardPrinter.php

@@ -376,7 +376,7 @@ final class BetterStandardPrinter extends Standard
         $printerNode = Strings::replace($printerNode, '#\/*\*(.*?)\*\/#');
 
         // remove # ...
-        $printerNode = Strings::replace($printerNode, '#\#(.*?)$#m');
+        $printerNode = Strings::replace($printerNode, '#^(\s+)?\#(.*?)$#m');
 
         // remove // ...
         return Strings::replace($printerNode, '#\/\/(.*?)$#m');