PHPCompatibility · wimg · Jul 11, 2020 · May 16, 2020
diff --git a/PHPCompatibility/Sniffs/ControlStructures/NewNonCapturingCatchSniff.php b/PHPCompatibility/Sniffs/ControlStructures/NewNonCapturingCatchSniff.php
@@ -0,0 +1,84 @@
+<?php
+/**
+ * PHPCompatibility, an external standard for PHP_CodeSniffer.
+ *
+ * @package   PHPCompatibility
+ * @copyright 2012-2020 PHPCompatibility Contributors
+ * @license   https://opensource.org/licenses/LGPL-3.0 LGPL3
+ * @link      https://github.com/PHPCompatibility/PHPCompatibility
+ */
+
+namespace PHPCompatibility\Sniffs\ControlStructures;
+
+use PHP_CodeSniffer\Files\File;
+use PHP_CodeSniffer\Util\Tokens;
+use PHPCompatibility\Sniff;
+
+/**
+ * Catching exceptions without capturing them to a variable is allowed since PHP 8.0.
+ *
+ * PHP version 8.0
+ *
+ * @link https://wiki.php.net/rfc/non-capturing_catches
+ * @link https://www.php.net/manual/en/language.exceptions.php#language.exceptions.catch
+ *
+ * @since 10.0.0
+ */
+class NewNonCapturingCatchSniff extends Sniff
+{
+
+    /**
+     * Returns an array of tokens this test wants to listen for.
+     *
+     * @since 10.0.0
+     *
+     * @return array
+     */
+    public function register()
+    {
+        return [\T_CATCH];
+    }
+
+    /**
+     * Processes this test, when one of its tokens is encountered.
+     *
+     * @since 10.0.0
+     *
+     * @param \PHP_CodeSniffer_File $phpcsFile The file being scanned.
+     * @param int                   $stackPtr  The position of the current token
+     *                                         in the stack passed in $tokens.
+     *
+     * @return void
+     */
+    public function process(File $phpcsFile, $stackPtr)
+    {
+        if ($this->supportsBelow('7.4') === false) {
+            return;
+        }
+
+        $tokens = $phpcsFile->getTokens();
+        $token  = $tokens[$stackPtr];
+
+        // Bow out during live coding.
+        if (isset($token['parenthesis_opener'], $token['parenthesis_closer']) === false) {
+            return;
+        }
+
+        $lastNonEmptyToken = $phpcsFile->findPrevious(
+            Tokens::$emptyTokens,
+            ($token['parenthesis_closer'] - 1),
+            $token['parenthesis_opener'],
+            true
+        );
+
+        if ($tokens[$lastNonEmptyToken]['code'] === \T_VARIABLE) {
+            return;
+        }
+
+        $phpcsFile->addError(
+            'Catching exceptions without capturing them to a variable is not supported in PHP 7.4 or earlier.',
+            $stackPtr,
+            'Found'
+        );
+    }
+}
diff --git a/PHPCompatibility/Tests/ControlStructures/NewNonCapturingCatchUnitTest.inc b/PHPCompatibility/Tests/ControlStructures/NewNonCapturingCatchUnitTest.inc
@@ -0,0 +1,34 @@
+<?php
+
+/**
+ * Valid pre-PHP 8.0.
+ */
+try {
+    foo();
+} catch (SomeException $ex) {
+    die($ex->getMessage());
+} catch (ExceptionType1 | ExceptionType2 $e) {
+    die($e->getMessage());
+} catch (CustomException::class $e) {
+   // ...
+}
+
+/**
+ * Non-capturing catch - only valid in PHP 8.0+.
+ */
+try {
+   // Some code...
+} catch (ExceptionType1 | ExceptionType2) {
+   // Code to handle the exception.
+} catch (CustomException::class) {
+   // ...
+} catch ($exceptionObject::class) { // PHP 8 syntax - using ::class on objects.
+   // ...
+} catch (\Exception) {
+   // ...
+}
+
+// Don't throw errors during live code review.
+try {
+   // Some code...
+} catch (
diff --git a/PHPCompatibility/Tests/ControlStructures/NewNonCapturingCatchUnitTest.php b/PHPCompatibility/Tests/ControlStructures/NewNonCapturingCatchUnitTest.php
@@ -0,0 +1,105 @@
+<?php
+/**
+ * PHPCompatibility, an external standard for PHP_CodeSniffer.
+ *
+ * @package   PHPCompatibility
+ * @copyright 2012-2020 PHPCompatibility Contributors
+ * @license   https://opensource.org/licenses/LGPL-3.0 LGPL3
+ * @link      https://github.com/PHPCompatibility/PHPCompatibility
+ */
+
+namespace PHPCompatibility\Tests\ControlStructures;
+
+use PHPCompatibility\Tests\BaseSniffTest;
+
+/**
+ * Test the NewNonCapturingCatch sniff.
+ *
+ * @group newNonCapturingCatch
+ * @group controlStructures
+ * @group exceptions
+ *
+ * @covers \PHPCompatibility\Sniffs\ControlStructures\NewNonCapturingCatchSniff
+ *
+ * @since 10.0.0
+ */
+class NewNonCapturingCatchUnitTest extends BaseSniffTest
+{
+
+    /**
+     * testNewNonCapturingCatch
+     *
+     * @dataProvider dataNewNonCapturingCatch
+     *
+     * @param int $line The line number.
+     *
+     * @return void
+     */
+    public function testNewNonCapturingCatch($line)
+    {
+        $file = $this->sniffFile(__FILE__, '7.4');
+        $this->assertError($file, $line, 'Catching exceptions without capturing them to a variable is not supported in PHP 7.4 or earlier.');
+    }
+
+    /**
+     * Data provider.
+     *
+     * @see testNewNonCapturingCatch()
+     *
+     * @return array
+     */
+    public function dataNewNonCapturingCatch()
+    {
+        return array(
+            array(21),
+            array(23),
+            array(25),
+            array(27),
+        );
+    }
+
+
+    /**
+     * Verify no false positives are thrown for valid code.
+     *
+     * @dataProvider dataNoFalsePositives
+     *
+     * @param int $line The line number.
+     *
+     * @return void
+     */
+    public function testNoFalsePositives($line)
+    {
+        $file = $this->sniffFile(__FILE__, '7.4');
+        $this->assertNoViolation($file, $line);
+    }
+
+    /**
+     * Data provider.
+     *
+     * @see testNoFalsePositives()
+     *
+     * @return array
+     */
+    public function dataNoFalsePositives()
+    {
+        return array(
+            array(8),
+            array(10),
+            array(12),
+            array(34), // Live coding.
+        );
+    }
+
+
+    /**
+     * Verify no notices are thrown at all.
+     *
+     * @return void
+     */
+    public function testNoViolationsInFileOnValidVersion()
+    {
+        $file = $this->sniffFile(__FILE__, '8.0');
+        $this->assertNoViolation($file);
+    }
+}