[coding-style] Add NestedTernaryToMatchRector (#7572)

* [coding-style] Add NestedTernaryToMatchTrueRector

* fixes

* add identical support

* rename to NestedTernaryToMatchRector

* add fixture with different identical varible

* [ci-review] Rector Rectify

---------

Co-authored-by: GitHub Action <actions@github.com>

Author: TomasVotruba

rules-tests/CodingStyle/Rector/Assign/NestedTernaryToMatchRector/Fixture/negated_identical.php.inc

@@ -0,0 +1,31 @@
+<?php
+
+namespace Rector\Tests\CodingStyle\Rector\Assign\NestedTernaryToMatchRector\Fixture;
+
+final class NegatedIdentical
+{
+    public function run($value)
+    {
+        $result = $value !== 10 ? 'equal to 10' : ($value !== 5 ? 'equal to 5' : 'other value');
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\CodingStyle\Rector\Assign\NestedTernaryToMatchRector\Fixture;
+
+final class NegatedIdentical
+{
+    public function run($value)
+    {
+        $result = match (true) {
+            $value !== 10 => 'equal to 10',
+            $value !== 5 => 'equal to 5',
+            default => 'other value',
+        };
+    }
+}
+
+?>

rules-tests/CodingStyle/Rector/Assign/NestedTernaryToMatchRector/Fixture/nested_ternary.php.inc

@@ -0,0 +1,31 @@
+<?php
+
+namespace Rector\Tests\CodingStyle\Rector\Assign\NestedTernaryToMatchRector\Fixture;
+
+final class NestedTernaryToMatchRector
+{
+    public function run($value)
+    {
+        $result = $value > 10 ? 'greater than 10' : ($value === 10 ? 'equal to 10' : 'less than 10');
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\CodingStyle\Rector\Assign\NestedTernaryToMatchRector\Fixture;
+
+final class NestedTernaryToMatchRector
+{
+    public function run($value)
+    {
+        $result = match (true) {
+            $value > 10 => 'greater than 10',
+            $value === 10 => 'equal to 10',
+            default => 'less than 10',
+        };
+    }
+}
+
+?>

rules-tests/CodingStyle/Rector/Assign/NestedTernaryToMatchRector/Fixture/nested_ternary_with_identical.php.inc

@@ -0,0 +1,31 @@
+<?php
+
+namespace Rector\Tests\CodingStyle\Rector\Assign\NestedTernaryToMatchRector\Fixture;
+
+final class NestedTernaryWithIdentical
+{
+    public function run($value)
+    {
+        $result = $value === 10 ? 'equal to 10' : ($value === 5 ? 'equal to 5' : 'other value');
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\CodingStyle\Rector\Assign\NestedTernaryToMatchRector\Fixture;
+
+final class NestedTernaryWithIdentical
+{
+    public function run($value)
+    {
+        $result = match ($value) {
+            10 => 'equal to 10',
+            5 => 'equal to 5',
+            default => 'other value',
+        };
+    }
+}
+
+?>

rules-tests/CodingStyle/Rector/Assign/NestedTernaryToMatchRector/Fixture/nested_ternary_with_identical_different_values.php.inc

@@ -0,0 +1,31 @@
+<?php
+
+namespace Rector\Tests\CodingStyle\Rector\Assign\NestedTernaryToMatchRector\Fixture;
+
+final class NestedTernaryWithIdenticalDifferentValues
+{
+    public function run($value, $nextValue)
+    {
+        $result = $value === 10 ? 'equal to 10' : ($nextValue === 5 ? 'equal to 5' : 'other value');
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\CodingStyle\Rector\Assign\NestedTernaryToMatchRector\Fixture;
+
+final class NestedTernaryWithIdenticalDifferentValues
+{
+    public function run($value, $nextValue)
+    {
+        $result = match (true) {
+            $value === 10 => 'equal to 10',
+            $nextValue === 5 => 'equal to 5',
+            default => 'other value',
+        };
+    }
+}
+
+?>

rules-tests/CodingStyle/Rector/Assign/NestedTernaryToMatchRector/Fixture/skip_silent_conditions.php.inc

@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\Tests\CodingStyle\Rector\Assign\NestedTernaryToMatchRector\Fixture;
+
+final class SkipSilentConditions
+{
+    public function run($value)
+    {
+        $value = 5;
+
+        $result = $value > 10 ? 'greater than 10' : ($value === 10 ?: 'less than 10');
+    }
+}

rules-tests/CodingStyle/Rector/Assign/NestedTernaryToMatchRector/NestedTernaryToMatchRectorTest.php

@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\Tests\CodingStyle\Rector\Assign\NestedTernaryToMatchRector;
+
+use Iterator;
+use PHPUnit\Framework\Attributes\DataProvider;
+use Rector\Testing\PHPUnit\AbstractRectorTestCase;
+
+final class NestedTernaryToMatchRectorTest extends AbstractRectorTestCase
+{
+    #[DataProvider('provideData')]
+    public function test(string $filePath): void
+    {
+        $this->doTestFile($filePath);
+    }
+
+    public static function provideData(): Iterator
+    {
+        return self::yieldFilesFromDirectory(__DIR__ . '/Fixture');
+    }
+
+    public function provideConfigFilePath(): string
+    {
+        return __DIR__ . '/config/configured_rule.php';
+    }
+}

rules-tests/CodingStyle/Rector/Assign/NestedTernaryToMatchRector/config/configured_rule.php

@@ -0,0 +1,9 @@
+<?php
+
+declare(strict_types=1);
+
+use Rector\CodingStyle\Rector\Assign\NestedTernaryToMatchRector;
+use Rector\Config\RectorConfig;
+
+return RectorConfig::configure()
+    ->withRules([NestedTernaryToMatchRector::class]);

rules/CodingStyle/Rector/Assign/NestedTernaryToMatchRector.php

@@ -0,0 +1,161 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\CodingStyle\Rector\Assign;
+
+use PhpParser\Node;
+use PhpParser\Node\Expr;
+use PhpParser\Node\Expr\Assign;
+use PhpParser\Node\Expr\Match_;
+use PhpParser\Node\Expr\Ternary;
+use PhpParser\Node\Expr\Variable;
+use PhpParser\Node\MatchArm;
+use Rector\CodingStyle\ValueObject\ConditionAndResult;
+use Rector\Rector\AbstractRector;
+use Symplify\RuleDocGenerator\ValueObject\CodeSample\CodeSample;
+use Symplify\RuleDocGenerator\ValueObject\RuleDefinition;
+
+/**
+ * @see \Rector\Tests\CodingStyle\Rector\Assign\NestedTernaryToMatchRector\NestedTernaryToMatchRectorTest
+ */
+final class NestedTernaryToMatchRector extends AbstractRector
+{
+    public function getRuleDefinition(): RuleDefinition
+    {
+        return new RuleDefinition('Convert nested ternary expressions to match(true) statements', [
+            new CodeSample(
+                <<<'CODE_SAMPLE'
+class SomeClass
+{
+    public function getValue($input)
+    {
+        return $input > 100 ? 'more than 100' : ($input > 5 ? 'more than 5' : 'less');
+    }
+}
+CODE_SAMPLE
+                ,
+                <<<'CODE_SAMPLE'
+class SomeClass
+{
+    public function getValue($input)
+    {
+        return match (true) {
+            $input > 100 => 'more than 100',
+            $input > 5 => 'more than 5',
+            default => 'less',
+        };
+    }
+}
+CODE_SAMPLE
+            ),
+
+        ]);
+    }
+
+    /**
+     * @return array<class-string<Node>>
+     */
+    public function getNodeTypes(): array
+    {
+        return [Assign::class];
+    }
+
+    /**
+     * @param Assign $node
+     */
+    public function refactor(Node $node): ?Assign
+    {
+        if (! $node->expr instanceof Ternary) {
+            return null;
+        }
+
+        $ternary = $node->expr;
+
+        // traverse nested ternaries to collect them all
+        $currentTernary = $ternary;
+
+        /** @var ConditionAndResult[] $conditionsAndResults */
+        $conditionsAndResults = [];
+        $defaultExpr = null;
+
+        while ($currentTernary instanceof Ternary) {
+            if (!$currentTernary->if instanceof Expr) {
+                // short ternary, skip
+                return null;
+            }
+
+            $conditionsAndResults[] = new ConditionAndResult($currentTernary->cond, $currentTernary->if);
+
+            $currentTernary = $currentTernary->else;
+
+            if (! $currentTernary instanceof Ternary) {
+                $defaultExpr = $currentTernary;
+            }
+        }
+
+        // nothing long enough
+        if (count($conditionsAndResults) < 2 || ! $defaultExpr instanceof Expr) {
+            return null;
+        }
+
+        $match = $this->createMatch($conditionsAndResults, $defaultExpr);
+        $node->expr = $match;
+
+        return $node;
+    }
+
+    /**
+     * @param ConditionAndResult[] $conditionsAndResults
+     */
+    private function createMatch(array $conditionsAndResults, Expr $defaultExpr): Match_
+    {
+        $singleVariableName = $this->matchAlwaysIdenticalVariableName($conditionsAndResults);
+        if (is_string($singleVariableName)) {
+            $isVariableIdentical = true;
+            $match = new Match_(new Variable($singleVariableName));
+        } else {
+            $isVariableIdentical = false;
+            $match = new Match_($this->nodeFactory->createTrue());
+        }
+
+        foreach ($conditionsAndResults as $conditionAndResult) {
+            $match->arms[] = new MatchArm([
+                $isVariableIdentical ? $conditionAndResult->getIdenticalExpr() : $conditionAndResult->getConditionExpr(),
+            ], $conditionAndResult->getResultExpr());
+        }
+
+        $match->arms[] = new MatchArm(null, $defaultExpr);
+
+        return $match;
+    }
+
+    /**
+     * @param ConditionAndResult[] $conditionsAndResults
+     */
+    private function matchAlwaysIdenticalVariableName(array $conditionsAndResults): mixed
+    {
+        $identicalVariableNames = [];
+        foreach ($conditionsAndResults as $conditionAndResult) {
+            if (! $conditionAndResult->isIdenticalCompare()) {
+                return null;
+            }
+
+            $variableName = $conditionAndResult->getIdenticalVariableName();
+            if (! is_string($variableName)) {
+                return null;
+            }
+
+            $identicalVariableNames[] = $variableName;
+        }
+
+        $uniqueIdenticalVariableNames = array_unique($identicalVariableNames);
+        $uniqueIdenticalVariableNames = array_values($uniqueIdenticalVariableNames);
+
+        if (count($uniqueIdenticalVariableNames) === 1) {
+            return $uniqueIdenticalVariableNames[0];
+        }
+
+        return null;
+    }
+}