[CodeQuality] Add SimplifyTautologyTernaryRector

config/level/code-quality/code-quality.yml

@@ -20,3 +20,4 @@ services:
     Rector\Php\Rector\FuncCall\RemoveExtraParametersRector: ~
     Rector\CodeQuality\Rector\LogicalOr\LogicalOrToBooleanOrRector: ~
     Rector\CodeQuality\Rector\BinaryOp\SimplifyDeMorganBinaryRector: ~
+    Rector\CodeQuality\Rector\Ternary\SimplifyTautologyTernaryRector: ~

packages/CodeQuality/src/Rector/Ternary/SimplifyTautologyTernaryRector.php

@@ -0,0 +1,69 @@
+<?php declare(strict_types=1);
+
+namespace Rector\CodeQuality\Rector\Ternary;
+
+use PhpParser\Node;
+use PhpParser\Node\Expr\BinaryOp\Identical;
+use PhpParser\Node\Expr\BinaryOp\NotIdentical;
+use PhpParser\Node\Expr\Ternary;
+use Rector\PhpParser\Node\Maintainer\BinaryOpMaintainer;
+use Rector\Rector\AbstractRector;
+use Rector\RectorDefinition\CodeSample;
+use Rector\RectorDefinition\RectorDefinition;
+
+final class SimplifyTautologyTernaryRector extends AbstractRector
+{
+    /**
+     * @var BinaryOpMaintainer
+     */
+    private $binaryOpMaintainer;
+
+    public function __construct(BinaryOpMaintainer $binaryOpMaintainer)
+    {
+        $this->binaryOpMaintainer = $binaryOpMaintainer;
+    }
+
+    public function getDefinition(): RectorDefinition
+    {
+        return new RectorDefinition('Simplify tautology ternary to value', [
+            new CodeSample(
+                '$value = ($fullyQualifiedTypeHint !== $typeHint) ? $fullyQualifiedTypeHint : $typeHint;',
+                '$value = $fullyQualifiedTypeHint;'
+            ),
+        ]);
+    }
+
+    /**
+     * @return string[]
+     */
+    public function getNodeTypes(): array
+    {
+        return [Ternary::class];
+    }
+
+    /**
+     * @param Ternary $node
+     */
+    public function refactor(Node $node): ?Node
+    {
+        if (! $node->cond instanceof NotIdentical && ! $node->cond instanceof Identical) {
+            return null;
+        }
+
+        $isMatch = $this->binaryOpMaintainer->matchFirstAndSecondConditionNode(
+            $node->cond,
+            function (Node $leftNode) use ($node) {
+                return $this->areNodesEqual($leftNode, $node->if);
+            },
+            function (Node $leftNode) use ($node) {
+                return $this->areNodesEqual($leftNode, $node->else);
+            }
+        );
+
+        if ($isMatch === null) {
+            return null;
+        }
+
+        return $node->if;
+    }
+}

packages/CodeQuality/tests/Rector/Ternary/SimplifyTautologyTernaryRector/Fixture/fixture.php.inc

@@ -0,0 +1,37 @@
+<?php
+
+namespace Rector\CodeQuality\Tests\Rector\Ternary\SimplifyTautologyTernaryRector\Fixture;
+
+function tautologyTernary()
+{
+    $fullyQualifiedTypeHint = 1;
+    $typeHint = 2;
+
+    $value = ($fullyQualifiedTypeHint !== $typeHint) ? $fullyQualifiedTypeHint : $typeHint;
+    $value = ($typeHint !== $fullyQualifiedTypeHint) ? $fullyQualifiedTypeHint : $typeHint;
+
+    $value = ($typeHint === $fullyQualifiedTypeHint) ? $fullyQualifiedTypeHint : $typeHint;
+
+    $value = ($typeHint === $fullyQualifiedTypeHint) ? $typeHint : $fullyQualifiedTypeHint;
+}
+
+?>
+-----
+<?php
+
+namespace Rector\CodeQuality\Tests\Rector\Ternary\SimplifyTautologyTernaryRector\Fixture;
+
+function tautologyTernary()
+{
+    $fullyQualifiedTypeHint = 1;
+    $typeHint = 2;
+
+    $value = $fullyQualifiedTypeHint;
+    $value = $fullyQualifiedTypeHint;
+
+    $value = $fullyQualifiedTypeHint;
+
+    $value = $typeHint;
+}
+
+?>

packages/CodeQuality/tests/Rector/Ternary/SimplifyTautologyTernaryRector/SimplifyTautologyTernaryRectorTest.php

@@ -0,0 +1,19 @@
+<?php declare(strict_types=1);
+
+namespace Rector\CodeQuality\Tests\Rector\Ternary\SimplifyTautologyTernaryRector;
+
+use Rector\CodeQuality\Rector\Ternary\SimplifyTautologyTernaryRector;
+use Rector\Testing\PHPUnit\AbstractRectorTestCase;
+
+final class SimplifyTautologyTernaryRectorTest extends AbstractRectorTestCase
+{
+    public function test(): void
+    {
+        $this->doTestFiles([__DIR__ . '/Fixture/fixture.php.inc']);
+    }
+
+    protected function getRectorClass(): string
+    {
+        return SimplifyTautologyTernaryRector::class;
+    }
+}