Adding php -l linter

Summary: Adds a linter that checks php files for syntax errors using php -l

Test Plan:
Add a section to your .arclint file similar to:
```
"php": {
  "type": "php",
  "include": "(\\.php$)"
}
```

Then run arc lint on a php file with a syntax error.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: epriestley, jacobwalker0814, Korvin

Differential Revision: https://secure.phabricator.com/D10370

src/__phutil_library_map__.php

@@ -132,6 +132,8 @@ phutil_register_library_map(array(
     'ArcanistPEP8LinterTestCase' => 'lint/linter/__tests__/ArcanistPEP8LinterTestCase.php',
     'ArcanistPasteWorkflow' => 'workflow/ArcanistPasteWorkflow.php',
     'ArcanistPatchWorkflow' => 'workflow/ArcanistPatchWorkflow.php',
+    'ArcanistPhpLinter' => 'lint/linter/ArcanistPhpLinter.php',
+    'ArcanistPhpLinterTestCase' => 'lint/linter/__tests__/ArcanistPhpLinterTestCase.php',
     'ArcanistPhpcsLinter' => 'lint/linter/ArcanistPhpcsLinter.php',
     'ArcanistPhpcsLinterTestCase' => 'lint/linter/__tests__/ArcanistPhpcsLinterTestCase.php',
     'ArcanistPhrequentWorkflow' => 'workflow/ArcanistPhrequentWorkflow.php',
@@ -313,6 +315,8 @@ phutil_register_library_map(array(
     'ArcanistPEP8LinterTestCase' => 'ArcanistArcanistLinterTestCase',
     'ArcanistPasteWorkflow' => 'ArcanistWorkflow',
     'ArcanistPatchWorkflow' => 'ArcanistWorkflow',
+    'ArcanistPhpLinter' => 'ArcanistExternalLinter',
+    'ArcanistPhpLinterTestCase' => 'ArcanistArcanistLinterTestCase',
     'ArcanistPhpcsLinter' => 'ArcanistExternalLinter',
     'ArcanistPhpcsLinterTestCase' => 'ArcanistArcanistLinterTestCase',
     'ArcanistPhrequentWorkflow' => 'ArcanistWorkflow',

src/lint/linter/ArcanistPhpLinter.php

@@ -0,0 +1,85 @@
+<?php
+
+/**
+ * Uses "php -l" to detect syntax errors in PHP code.
+ */
+final class ArcanistPhpLinter extends ArcanistExternalLinter {
+
+  public function getInfoName() {
+    return 'php -l';
+  }
+
+  public function getInfoURI() {
+    return 'http://php.net/';
+  }
+
+  public function getInfoDescription() {
+    return pht(
+      'Checks for syntax errors in php files.');
+  }
+
+  public function getLinterName() {
+    return 'PHP';
+  }
+
+  public function getLinterConfigurationName() {
+    return 'php';
+  }
+
+  public function getMandatoryFlags() {
+    return array('-l');
+  }
+
+  public function getInstallInstructions() {
+    return pht('Install PHP.');
+  }
+
+  public function getDefaultBinary() {
+    return 'php';
+  }
+
+  public function getVersion() {
+    list($stdout) = execx('%C --version', $this->getExecutableCommand());
+
+    $matches = array();
+    $regex = '/^PHP (?P<version>\d+\.\d+\.\d+)\b/';
+    if (preg_match($regex, $stdout, $matches)) {
+      return $matches['version'];
+    } else {
+      return false;
+    }
+  }
+
+  public function shouldExpectCommandErrors() {
+    return true;
+  }
+
+  public function supportsReadDataFromStdin() {
+    return false;
+  }
+
+  protected function parseLinterOutput($path, $err, $stdout, $stderr) {
+    // Older versions of php had both on $stdout, newer ones split it
+    // Combine $stdout and $stderr for consistency
+    $stdout = $stderr."\n".$stdout;
+    $matches = array();
+    $regex = '/PHP (?<type>.+?) error:\s+(?<error>.*?)\s+in\s+(?<file>.*?)'.
+      '\s+on line\s+(?<line>\d*)/';
+    if (preg_match($regex, $stdout, $matches)) {
+      $type = strtolower($matches['type']);
+      $message = new ArcanistLintMessage();
+      $message->setPath($matches['file']);
+      $message->setLine($matches['line']);
+      $message->setCode('php.'.$type);
+      $message->setDescription('This file contains a '.$type.' error: '.
+        $matches['error'].' on line '.$matches['line']);
+      $message->setSeverity(ArcanistLintSeverity::SEVERITY_ERROR);
+
+      // php -l only returns the first error
+      return array($message);
+    }
+
+    return array();
+  }
+
+}

src/lint/linter/__tests__/ArcanistPhpLinterTestCase.php

@@ -0,0 +1,11 @@
+<?php
+
+final class ArcanistPhpLinterTestCase extends ArcanistArcanistLinterTestCase {
+
+  public function testPHPLint() {
+    $this->executeTestsInDirectory(
+      dirname(__FILE__).'/php/',
+      new ArcanistPhpLinter());
+  }
+
+}

src/lint/linter/__tests__/php/fatal.lint-test

@@ -0,0 +1,7 @@
+<?php
+
+function f() {
+  $this = "cannot be re-assigned";
+}
+~~~~~~~~~
+error:4:

src/lint/linter/__tests__/php/no-errors.lint-test

@@ -0,0 +1,6 @@
+<?php
+
+function f() {
+  return "foobar";
+}
+~~~~~~~~~~

src/lint/linter/__tests__/php/syntax.lint-test

@@ -0,0 +1,7 @@
+<?php
+
+function f() {
+  this is bad syntax;
+}
+~~~~~~~~~
+error:4: