Adding CLI option for listing plugins

Fixes #5920

src/cli/plugin/plugin.js

@@ -3,6 +3,7 @@ const fromRoot = utils('fromRoot');
 const settingParser = require('./setting_parser');
 const installer = require('./plugin_installer');
 const remover = require('./plugin_remover');
+const lister = require('./plugin_lister');
 const pluginLogger = require('./plugin_logger');
 
 export default function pluginCli(program) {
@@ -24,12 +25,17 @@ export default function pluginCli(program) {
     if (settings.action === 'remove') {
       remover.remove(settings, logger);
     }
+    if (settings.action === 'list') {
+      lister.list(settings, logger);
+    }
+
   }
 
   program
     .command('plugin')
     .option('-i, --install <org>/<plugin>/<version>', 'The plugin to install')
     .option('-r, --remove <plugin>', 'The plugin to remove')
+    .option('-l, --list', 'List installed plugins')
     .option('-q, --quiet', 'Disable all process messaging except errors')
     .option('-s, --silent', 'Disable all process messaging')
     .option('-u, --url <url>', 'Specify download url')

src/cli/plugin/plugin_lister.js

@@ -0,0 +1,18 @@
+const fs = require('fs');
+
+module.exports = {
+  list: list
+};
+
+function list(settings, logger) {
+  fs.readdir(settings.pluginDir, function (err, files) {
+
+    var pluginFiles = files.filter(function (file) {
+      return file[0] !== '.';
+    });
+
+    pluginFiles.forEach(function (pluginFile) {
+      logger.log(pluginFile);
+    });
+  });
+}

src/cli/plugin/setting_parser.js

@@ -84,8 +84,12 @@ export default function createSettingParser(options) {
       settings.package = parts.shift();
     }
 
-    if (!settings.action || (options.install && options.remove)) {
-      throw new Error('Please specify either --install or --remove.');
+    if (options.list) {
+      settings.action = 'list';
+    }
+
+    if (!settings.action || (options.install && options.remove && options.list)) {
+      throw new Error('Please specify either --install, --remove, or --list.');
     }
 
     settings.pluginDir = options.pluginDir;