Add PrettierLinter (MobileNativeFoundation#3)

README.md

@@ -8,6 +8,7 @@ Pinterest.
 - [Checkstyle](#checkstyle)
 - [ESLint](#eslint)
 - [Go Vet](#go-vet)
+- [Prettier](#prettier)
 - [Python Imports](#python-imports)
 - [Python isort](#python-isort)
 - [Python Requirements](#python-requirements)
@@ -84,6 +85,20 @@ Lints JavaScript and JSX files using [ESLint](https://eslint.org/).
 }
 ```
 
+
+### Prettier
+
+Formats JavaScript using [Prettier](https://prettier.io/).
+
+```json
+{
+    "type": "prettier",
+    "include": "(\\.js$)",
+    "bin": "./node_modules/.bin/prettier",
+    "prettier.cwd": "./"
+}
+```
+
 ### Go Vet
 
 Uses the [Go vet command](https://golang.org/cmd/vet/) to lint for suspicious

__phutil_library_map__.php

@@ -11,6 +11,7 @@
   'class' => array(
     'ApacheThriftGeneratedLinter' => 'src/ApacheThriftGeneratedLinter.php',
     'ApacheThriftLinter' => 'src/ApacheThriftLinter.php',
+    'PrettierLinter' => 'src/PrettierLinter.php',
     'CheckstyleLinter' => 'src/CheckstyleLinter.php',
     'ESLintLinter' => 'src/ESLintLinter.php',
     'GoVetLinter' => 'src/GoVetLinter.php',
@@ -22,6 +23,7 @@
   'xmap' => array(
     'ApacheThriftGeneratedLinter' => 'ArcanistLinter',
     'ApacheThriftLinter' => 'ArcanistExternalLinter',
+    'PrettierLinter' => 'ArcanistExternalLinter',
     'CheckstyleLinter' => 'ArcanistExternalLinter',
     'ESLintLinter' => 'ArcanistExternalLinter',
     'GoVetLinter' => 'ArcanistExternalLinter',

src/PrettierLinter.php

@@ -0,0 +1,101 @@
+<?php
+/**
+ * Copyright 2018 Pinterest, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Lints JavaScript and JSX files using Prettier
+ */
+final class PrettierLinter extends ArcanistExternalLinter {
+  private $cwd = '';
+
+  public function getInfoName() {
+    return 'Prettier';
+  }
+
+  public function getInfoURI() {
+    return 'https://prettier.io/';
+  }
+
+  public function getInfoDescription() {
+    return pht('An opinionated code formatter with canonicalized AST-derived output');
+  }
+
+  public function getLinterName() {
+    return 'PRETTIER';
+  }
+
+  public function getLinterConfigurationName() {
+    return 'prettier';
+  }
+
+  public function getDefaultBinary() {
+    list($err, $stdout, $stderr) = exec_manual('yarn -s --cwd %s which prettier', $this->getProjectRoot() . '/' . $this->cwd);
+    $binaryPath = strtok($stdout, "\n");
+    return $binaryPath;
+  }
+
+  public function getVersion() {
+    list($err, $stdout, $stderr) = exec_manual('%C -v', $this->getExecutableCommand());
+    return $stdout;
+  }
+
+  public function getLinterConfigurationOptions() {
+    $options = array(
+      'prettier.cwd' => array(
+        'type' => 'optional string',
+        'help' => pht('Specify a project sub-directory for both the local prettier install and the sub-directory to lint within.'),
+      ),
+    );
+    return $options + parent::getLinterConfigurationOptions();
+  }
+
+  public function setLinterConfigurationValue($key, $value) {
+    switch ($key) {
+      case 'prettier.cwd':
+        $this->cwd = $value;
+        return;
+    }
+    return parent::setLinterConfigurationValue($key, $value);
+  }
+
+  public function getInstallInstructions() {
+    return pht(
+      'run `%s` to install yarn globally (needed for specifying --cwd), and `%s` to add prettier to your project (configurable at prettier.cwd).',
+      'npm install --global yarn',
+      'yarn add --dev prettier'
+    );
+  }
+
+  protected function parseLinterOutput($path, $err, $stdout, $stderr) {
+    if ($err) {
+      return false;
+    }
+
+    $message = new ArcanistLintMessage();
+    $message->setPath($path);
+    $message->setSeverity(ArcanistLintSeverity::SEVERITY_AUTOFIX);
+    $message->setName('Prettier Format');
+    $message->setLine(1);
+    $message->setCode($this->getLinterName());
+    $message->setChar(1);
+    $message->setDescription('Your file has not been prettier-ified');
+    $message->setOriginalText($this->getData($path));
+    $message->setReplacementText($stdout);
+    $messages[] = $message;
+
+    return $messages;
+  }
+}