adds checkstyle compatible renderer, suitable for cs2pr or reviewdog

README.rst

@@ -194,6 +194,7 @@ At the moment PHPMD comes with the following renderers:
 - *json*, formats JSON report.
 - *ansi*, a command line friendly format.
 - *github*, a format that GitHub Actions understands.
+- *checkstyle*, language and tool agnostic XML format
 
 PHPMD for enterprise
 --------------------

src/main/php/PHPMD/Renderer/CheckStyleRenderer.php

@@ -0,0 +1,106 @@
+<?php
+
+namespace PHPMD\Renderer;
+
+use PHPMD\PHPMD;
+use PHPMD\Report;
+use PHPMD\Renderer\XMLRenderer;
+
+/**
+ * This class will render a Java-checkstyle compatible xml-report.
+ * for use with cs2pr and others
+ */
+class CheckStyleRenderer extends XMLRenderer
+{
+    /**
+     * Temporary property that holds the name of the last rendered file, it is
+     * used to detect the next processed file.
+     *
+     * @var string
+     */
+    private $fileName;
+
+    /**
+     * Get a violation severity level according to the priority
+     * of the rule that's being broken
+     * @see https://checkstyle.sourceforge.io/version/4.4/property_types.html#severity
+     * - priority 1 maps to error level severity
+     * - priority 2 maps to warning level severity
+     * - priority > 2 maps to info level severity
+     *
+     * @param integer $priority priority of the broken rule
+     * @return string either error, warning or info
+     */
+    protected function mapPriorityToSeverity($priority)
+    {
+        if ($priority > 2) {
+            return 'info';
+        }
+
+        return (int) $priority === 2 ? 'warning' : 'error';
+    }
+    /**
+     * This method will be called when the engine has finished the source analysis
+     * phase.
+     *
+     * @param \PHPMD\Report $report
+     */
+    public function renderReport(Report $report)
+    {
+        $writer = $this->getWriter();
+        $writer->write('<checkstyle>');
+        $writer->write(\PHP_EOL);
+
+        foreach ($report->getRuleViolations() as $violation) {
+            $fileName = $violation->getFileName();
+
+            if ($this->fileName !== $fileName) {
+                // Not first file
+                if (null !== $this->fileName) {
+                    $writer->write('  </file>' . \PHP_EOL);
+                }
+                // Store current file name
+                $this->fileName = $fileName;
+
+                $writer->write('  <file name="' . $fileName . '">' . \PHP_EOL);
+            }
+
+            $rule = $violation->getRule();
+
+            $writer->write('    <error');
+            $writer->write(' line="' . $violation->getBeginLine() . '"');
+            $writer->write(' endline="' . $violation->getEndLine() . '"');
+            $writer->write(\sprintf(' severity="%s"', $this->mapPriorityToSeverity($rule->getPriority())));
+            $writer->write(\sprintf(
+                ' message="%s (%s, %s) "',
+                \htmlspecialchars($violation->getDescription()),
+                $rule->getName(),
+                $rule->getRuleSetName()
+            ));
+
+            $this->maybeAdd('package', $violation->getNamespaceName());
+            $this->maybeAdd('externalInfoUrl', $rule->getExternalInfoUrl());
+            $this->maybeAdd('function', $violation->getFunctionName());
+            $this->maybeAdd('class', $violation->getClassName());
+            $this->maybeAdd('method', $violation->getMethodName());
+            //$this->_maybeAdd('variable', $violation->getVariableName());
+
+            $writer->write(' />' . \PHP_EOL);
+        }
+
+        // Last file and at least one violation
+        if (null !== $this->fileName) {
+            $writer->write('  </file>' . \PHP_EOL);
+        }
+
+        foreach ($report->getErrors() as $error) {
+            $writer->write('  <file name="' . $error->getFile() . '">');
+            $writer->write($error->getFile());
+            $writer->write('<error  msg="');
+            $writer->write(\htmlspecialchars($error->getMessage()));
+            $writer->write(' severity="error" />' . \PHP_EOL);
+        }
+
+        $writer->write('</checkstyle>' . \PHP_EOL);
+    }
+}

src/main/php/PHPMD/Renderer/XMLRenderer.php

@@ -120,7 +120,7 @@ public function renderReport(Report $report)
      * @param string $value The attribute value.
      * @return void
      */
-    private function maybeAdd($attr, $value)
+    protected function maybeAdd($attr, $value)
     {
         if ($value === null || trim($value) === '') {
             return;

src/main/php/PHPMD/TextUI/CommandLineOptions.php

@@ -22,6 +22,7 @@
 use PHPMD\Renderer\HTMLRenderer;
 use PHPMD\Renderer\JSONRenderer;
 use PHPMD\Renderer\TextRenderer;
+use PHPMD\Renderer\CheckStyleRenderer;
 use PHPMD\Renderer\XMLRenderer;
 use PHPMD\Rule;
 
@@ -209,8 +210,9 @@ public function __construct(array $args, array $availableRuleSets = array())
                 case '--reportfile-html':
                 case '--reportfile-text':
                 case '--reportfile-xml':
+                case '--reportfile-checkstyle':
                 case '--reportfile-json':
-                    preg_match('(^\-\-reportfile\-(xml|html|text|json)$)', $arg, $match);
+                    preg_match('(^\-\-reportfile\-(xml|checkstyle|html|text|json)$)', $arg, $match);
                     $this->reportFiles[$match[1]] = array_shift($args);
                     break;
                 default:
@@ -397,6 +399,8 @@ public function createRenderer($reportFormat = null)
                 return $this->createAnsiRenderer();
             case 'github':
                 return $this->createGitHubRenderer();
+            case 'checkstyle':
+                return $this->createCheckStyleRenderer();
             default:
                 return $this->createCustomRenderer();
         }
@@ -450,6 +454,14 @@ protected function createJsonRenderer()
         return new JSONRenderer();
     }
 
+     /**
+     * @return \PHPMD\Renderer\JSONRenderer
+     */
+    protected function createCheckStyleRenderer()
+    {
+        return new CheckStyleRenderer();
+    }
+
     /**
      * @return \PHPMD\AbstractRenderer
      * @throws \InvalidArgumentException

src/test/php/PHPMD/Renderer/CheckStyleRendererTest.php

@@ -0,0 +1,105 @@
+<?php
+/**
+ * This file is part of PHP Mess Detector.
+ *
+ * Copyright (c) Manuel Pichler <mapi@phpmd.org>.
+ * All rights reserved.
+ *
+ * Licensed under BSD License
+ * For full copyright and license information, please see the LICENSE file.
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @author Manuel Pichler <mapi@phpmd.org>
+ * @copyright Manuel Pichler. All rights reserved.
+ * @license https://opensource.org/licenses/bsd-license.php BSD License
+ * @link http://phpmd.org/
+ */
+
+namespace PHPMD\Renderer;
+
+use PHPMD\AbstractTest;
+use PHPMD\ProcessingError;
+use PHPMD\Stubs\WriterStub;
+
+/**
+ * Test case for the xml renderer implementation.
+ *
+ * @covers \PHPMD\Renderer\XMLRenderer
+ */
+class CheckStyleRendererTest extends AbstractTest
+{
+    /**
+     * testRendererCreatesExpectedNumberOfXmlElements
+     *
+     * @return void
+     */
+    public function testRendererCreatesExpectedNumberOfXmlElements()
+    {
+        // Create a writer instance.
+        $writer = new WriterStub();
+
+        $violations = array(
+            $this->getRuleViolationMock('/bar.php'),
+            $this->getRuleViolationMock('/foo.php'),
+            $this->getRuleViolationMock('/foo.php', 23, 42, null, 'foo <?php bar'),
+        );
+
+        $report = $this->getReportWithNoViolation();
+        $report->expects($this->once())
+            ->method('getRuleViolations')
+            ->will($this->returnValue(new \ArrayIterator($violations)));
+        $report->expects($this->once())
+            ->method('getErrors')
+            ->will($this->returnValue(new \ArrayIterator(array())));
+
+        $renderer = new XMLRenderer();
+        $renderer->setWriter($writer);
+
+        $renderer->start();
+        $renderer->renderReport($report);
+        $renderer->end();
+
+        $this->assertXmlEquals(
+            $writer->getData(),
+            'renderer/xml_renderer_expected1.xml'
+        );
+    }
+
+    /**
+     * testRendererAddsProcessingErrorsToXmlReport
+     *
+     * @return void
+     * @since 1.2.1
+     */
+    public function testRendererAddsProcessingErrorsToXmlReport()
+    {
+        // Create a writer instance.
+        $writer = new WriterStub();
+
+        $processingErrors = array(
+            new ProcessingError('Failed for file "/tmp/foo.php".'),
+            new ProcessingError('Failed for file "/tmp/bar.php".'),
+            new ProcessingError('Failed for file "/tmp/baz.php".'),
+        );
+
+        $report = $this->getReportWithNoViolation();
+        $report->expects($this->once())
+            ->method('getRuleViolations')
+            ->will($this->returnValue(new \ArrayIterator(array())));
+        $report->expects($this->once())
+            ->method('getErrors')
+            ->will($this->returnValue(new \ArrayIterator($processingErrors)));
+
+        $renderer = new XMLRenderer();
+        $renderer->setWriter($writer);
+
+        $renderer->start();
+        $renderer->renderReport($report);
+        $renderer->end();
+
+        $this->assertXmlEquals(
+            $writer->getData(),
+            'renderer/xml_renderer_processing_errors.xml'
+        );
+    }
+}

src/test/php/PHPMD/TextUI/CommandLineOptionsTest.php

@@ -236,7 +236,7 @@ public function testCliUsageContainsAutoDiscoveredRenderers()
         $args = array(__FILE__, __FILE__, 'text', 'codesize');
         $opts = new CommandLineOptions($args);
 
-        $this->assertContains('Available formats: ansi, github, html, json, text, xml.', $opts->usage());
+        $this->assertContains('Available formats: ansi, checkstyle, github, html, json, text, xml.', $opts->usage());
     }
 
     /**

src/test/php/PHPMD/TextUI/CommandTest.php

@@ -122,6 +122,8 @@ public function testWithMultipleReportFiles()
             $text = self::createTempFileUri(),
             '--reportfile-json',
             $json = self::createTempFileUri(),
+            '--reportfile-checkstyle',
+            $checkstyle = self::createTempFileUri(),
         );
 
         Command::main($args);
@@ -130,6 +132,7 @@ public function testWithMultipleReportFiles()
         $this->assertFileExists($html);
         $this->assertFileExists($text);
         $this->assertFileExists($json);
+        $this->assertFileExists($checkstyle);
     }
 
     public function testOutput()