Add CSSLint linter to Arcanist

See: https://github.com/facebook/arcanist/pull/93

Reviewed by: epriestley

src/__phutil_library_map__.php

@@ -28,6 +28,7 @@ phutil_register_library_map(array(
     'ArcanistBrowseWorkflow' => 'workflow/ArcanistBrowseWorkflow.php',
     'ArcanistBundle' => 'parser/ArcanistBundle.php',
     'ArcanistBundleTestCase' => 'parser/__tests__/ArcanistBundleTestCase.php',
+    'ArcanistCSSLintLinter' => 'lint/linter/ArcanistCSSLintLinter.php',
     'ArcanistCallConduitWorkflow' => 'workflow/ArcanistCallConduitWorkflow.php',
     'ArcanistCapabilityNotSupportedException' => 'workflow/exception/ArcanistCapabilityNotSupportedException.php',
     'ArcanistChooseInvalidRevisionException' => 'exception/ArcanistChooseInvalidRevisionException.php',
@@ -189,6 +190,7 @@ phutil_register_library_map(array(
     'ArcanistBritishTestCase' => 'ArcanistTestCase',
     'ArcanistBrowseWorkflow' => 'ArcanistBaseWorkflow',
     'ArcanistBundleTestCase' => 'ArcanistTestCase',
+    'ArcanistCSSLintLinter' => 'ArcanistLinter',
     'ArcanistCallConduitWorkflow' => 'ArcanistBaseWorkflow',
     'ArcanistCapabilityNotSupportedException' => 'Exception',
     'ArcanistChooseInvalidRevisionException' => 'Exception',

src/lint/linter/ArcanistCSSLintLinter.php

@@ -0,0 +1,125 @@
+<?php
+
+/**
+ * Uses "CSS lint" to detect checkstyle errors in css code.
+ * To use this linter, you must install CSS lint.
+ * ##npm install csslint -g## (don't forget the -g flag or NPM will install
+ * the package locally).
+ *
+ * Based on ArcanistPhpcsLinter.php
+ *
+ *   lint.csslint.options
+ *   lint.csslint.bin
+ *
+ * @group linter
+ */
+final class ArcanistCSSLintLinter extends ArcanistLinter {
+
+  private $reports;
+
+  public function getLinterName() {
+    return 'CSSLint';
+  }
+
+  public function getLintSeverityMap() {
+    return array();
+  }
+
+  public function getLintNameMap() {
+    return array();
+  }
+
+  public function getCSSLintOptions() {
+    $working_copy = $this->getEngine()->getWorkingCopy();
+
+    $options = $working_copy->getConfig('lint.csslint.options');
+
+    return $options;
+  }
+
+  private function getCSSLintPath() {
+    $working_copy = $this->getEngine()->getWorkingCopy();
+    $bin = $working_copy->getConfig('lint.csslint.bin');
+
+    if ($bin === null) {
+      $bin = 'csslint';
+    }
+
+    return $bin;
+  }
+
+  public function willLintPaths(array $paths) {
+    $csslint_bin = $this->getCSSLintPath();
+    $csslint_options = $this->getCSSLintOptions();
+    $futures = array();
+
+    foreach ($paths as $path) {
+      $filepath = $this->getEngine()->getFilePathOnDisk($path);
+      $this->reports[$path] = new TempFile();
+      $futures[$path] = new ExecFuture('%C %C --format=lint-xml >%s %s',
+        $csslint_bin,
+        $csslint_options,
+        $this->reports[$path],
+        $filepath);
+    }
+
+    foreach (Futures($futures)->limit(8) as $path => $future) {
+      $this->results[$path] = $future->resolve();
+    }
+
+    libxml_use_internal_errors(true);
+  }
+
+  public function lintPath($path) {
+    list($rc, $stdout) = $this->results[$path];
+
+    $report = Filesystem::readFile($this->reports[$path]);
+
+    if ($report) {
+      $report_dom = new DOMDocument();
+      libxml_clear_errors();
+      $report_dom->loadXML($report);
+    }
+    if (!$report || libxml_get_errors()) {
+      throw new ArcanistUsageException('CSS Linter failed to load ' .
+        'reporting file. Something happened when running csslint. ' .
+        "Output:\n$stdout" .
+        "\nTry running lint with --trace flag to get more details.");
+    }
+
+    $files = $report_dom->getElementsByTagName('file');
+    foreach ($files as $file) {
+      foreach ($file->childNodes as $child) {
+        if (!($child instanceof DOMElement)) {
+          continue;
+        }
+
+        $data = $this->getData($path);
+        $lines = explode("\n", $data);
+        $name = $this->getLinterName() . ' - ' . $child->getAttribute('reason');
+        $severity = ($child->getAttribute('severity') == 'warning')
+          ? ArcanistLintSeverity::SEVERITY_WARNING
+          : ArcanistLintSeverity::SEVERITY_ERROR;
+
+        $message = new ArcanistLintMessage();
+        $message->setPath($path);
+        $message->setLine($child->getAttribute('line'));
+        $message->setChar($child->getAttribute('char'));
+        $message->setCode($child->getAttribute('severity'));
+        $message->setName($name);
+        $message->setDescription(
+          $child->getAttribute('reason').
+          "\nEvidence:".$child->getAttribute('evidence'));
+        $message->setSeverity($severity);
+
+        if ($child->hasAttribute('line')) {
+          $line = $lines[$child->getAttribute('line') - 1];
+          $text = substr($line, $child->getAttribute('char') - 1);
+          $message->setOriginalText($text);
+        }
+
+        $this->addLintMessage($message);
+      }
+    }
+  }
+}