Treat the | in a catch type list as a union type separator

PhpCollective/Sniffs/Operators/OperatorSpacingSniff.php

@@ -0,0 +1,99 @@
+<?php
+
+/**
+ * MIT License
+ * For full license information, please view the LICENSE file that was distributed with this source code.
+ */
+
+namespace PhpCollective\Sniffs\Operators;
+
+use PHP_CodeSniffer\Files\File;
+use PHP_CodeSniffer\Standards\PSR12\Sniffs\Operators\OperatorSpacingSniff as Psr12OperatorSpacingSniff;
+
+/**
+ * Operator spacing, with the `|` in a `catch` type list treated as a type separator.
+ *
+ * PHP tokenizes a catch type list (`catch (ValueError|TypeError $e)`) with plain `T_BITWISE_OR`
+ * tokens, so the inherited sniff reads it as a bitwise operator and demands a space on both
+ * sides. That is the opposite of the type separator rule enforced by
+ * `Universal.Operators.TypeSeparatorSpacing`, which only listens for `T_TYPE_UNION` and never
+ * sees a catch list. Downstream projects such as cakephp/cakephp had to silence
+ * `PSR12.Operators.OperatorSpacing.NoSpaceBefore` and `PSR12.Operators.OperatorSpacing.NoSpaceAfter`
+ * in their `phpcs.xml` to allow the no-space form, and that also silenced the real bitwise
+ * operators. This sniff keeps every inherited check and treats the catch-list `|` like a union
+ * type separator: no space, fixable.
+ */
+class OperatorSpacingSniff extends Psr12OperatorSpacingSniff
+{
+    /**
+     * @inheritDoc
+     */
+    public function process(File $phpcsFile, int $stackPtr)
+    {
+        $tokens = $phpcsFile->getTokens();
+
+        if ($tokens[$stackPtr]['code'] === T_BITWISE_OR && $this->isCatchTypeSeparator($stackPtr, $tokens) === true) {
+            $this->checkTypeSeparator($phpcsFile, $stackPtr, $tokens, true);
+            $this->checkTypeSeparator($phpcsFile, $stackPtr, $tokens, false);
+
+            return;
+        }
+
+        return parent::process($phpcsFile, $stackPtr);
+    }
+
+    /**
+     * Whether the `|` at `$stackPtr` is a separator in a `catch` type list.
+     *
+     * The tokenizer does not mark these as `T_TYPE_UNION`; they are plain `T_BITWISE_OR` inside
+     * the parenthesis that the `catch` keyword owns. The innermost enclosing parenthesis is the
+     * last entry of `nested_parenthesis` (keys are open-token positions, in source order). A
+     * real bitwise `|` in the catch body has no parenthesis owned by `catch`, so it falls
+     * through to the inherited bitwise-operator check.
+     *
+     * @param int                            $stackPtr Position of the `|`.
+     * @param array<int, array<string, mixed>> $tokens The token stack.
+     *
+     * @return bool
+     */
+    protected function isCatchTypeSeparator(int $stackPtr, array $tokens): bool
+    {
+        $nested = $tokens[$stackPtr]['nested_parenthesis'] ?? [];
+        $open   = array_key_last($nested);
+        if ($open === null) {
+            return false;
+        }
+
+        $owner = $tokens[$open]['parenthesis_owner'] ?? null;
+
+        return $owner !== null && $tokens[$owner]['code'] === T_CATCH;
+    }
+
+    /**
+     * Reports and fixes the spacing on one side of the type separator. A union type separator
+     * carries no space, so any whitespace here is the violation.
+     *
+     * @param \PHP_CodeSniffer\Files\File          $phpcsFile The file being scanned.
+     * @param int                                  $stackPtr  Position of the `|`.
+     * @param array<int, array<string, mixed>>     $tokens    The token stack.
+     * @param bool                                 $before    Check the side before the operator.
+     *
+     * @return void
+     */
+    protected function checkTypeSeparator(File $phpcsFile, int $stackPtr, array $tokens, bool $before): void
+    {
+        $index = $before ? $stackPtr - 1 : $stackPtr + 1;
+        if (!isset($tokens[$index]) || $tokens[$index]['code'] !== T_WHITESPACE) {
+            return;
+        }
+
+        $side    = $before ? 'before' : 'after';
+        $message = 'No space %s the `|` in a catch type list (it is a type separator); found %d';
+        $code    = $before ? 'SpaceBefore' : 'SpaceAfter';
+        $fix     = $phpcsFile->addFixableError($message, $stackPtr, $code, [$side, strlen($tokens[$index]['content'])]);
+
+        if ($fix === true) {
+            $phpcsFile->fixer->replaceToken($index, '');
+        }
+    }
+}

PhpCollective/ruleset.xml

@@ -237,8 +237,13 @@
         <exclude name="PSR12.Files.OpenTag"/>
         <!-- Long casts are covered by SlevomatCodingStandard.PHP.TypeCast, which catches more. -->
         <exclude name="PSR12.Keywords.ShortFormTypeKeywords"/>
+        <!-- Replaced by PhpCollective.Operators.OperatorSpacing, which additionally treats the
+             `|` in a catch type list as a type separator (no space) instead of a bitwise operator. -->
+        <exclude name="PSR12.Operators.OperatorSpacing"/>
     </rule>
 
+    <rule ref="PhpCollective.Operators.OperatorSpacing"/>
+
     <!--
         Three rules used to report every long cast. SlevomatCodingStandard.PHP.TypeCast above is
         the only one that covers all of them - it also rewrites `(double)` to `(float)` and copes

tests/PhpCollective/Sniffs/Operators/OperatorSpacingSniffTest.php

@@ -0,0 +1,34 @@
+<?php
+
+/**
+ * MIT License
+ * For full license information, please view the LICENSE file that was distributed with this source code.
+ */
+
+namespace PhpCollective\Test\PhpCollective\Sniffs\Operators;
+
+use PhpCollective\Sniffs\Operators\OperatorSpacingSniff;
+use PhpCollective\Test\TestCase;
+
+class OperatorSpacingSniffTest extends TestCase
+{
+    /**
+     * @return void
+     */
+    public function testOperatorSpacingSniff(): void
+    {
+        // The `|` in a catch type list is a type separator: no space allowed, so the spaced
+        // separator is reported on both sides (2 fixable errors). The real bitwise operator in
+        // the catch body keeps the inherited spacing rule: the missing space after it is the
+        // third fixable error, proving the inherited check still runs for genuine operators.
+        $this->assertSnifferFindsFixableErrors(new OperatorSpacingSniff(), 3, 3);
+    }
+
+    /**
+     * @return void
+     */
+    public function testOperatorSpacingFixer(): void
+    {
+        $this->assertSnifferCanFixErrors(new OperatorSpacingSniff(), 3);
+    }
+}

tests/_data/OperatorSpacing/after.php

@@ -0,0 +1,7 @@
+<?php
+
+try {
+    doThing();
+} catch (ValueError|TypeError $e) {
+    $x = $a | $b;
+}

tests/_data/OperatorSpacing/before.php

@@ -0,0 +1,7 @@
+<?php
+
+try {
+    doThing();
+} catch (ValueError | TypeError $e) {
+    $x = $a |$b;
+}