Better error handling when 'generator-' prefix is specified (#520)

Author: clifflee

lib/cli.js

@@ -135,6 +135,20 @@ function init() {
       return;
     }
 
+    // More detailed error message
+    // If users type in generator name with prefix 'generator-'
+    if (cmd.startsWith('generator-')) {
+      const generatorName = cmd.replace('generator-', '');
+      const generatorCommand = chalk.yellow('yo ' + generatorName);
+
+      console.log(chalk.red('Installed generators don\'t need the "generator-" prefix.'));
+      console.log(`In the future, run ${generatorCommand} instead!\n`);
+
+      env.run(generatorName, firstCmd.opts);
+
+      return;
+    }
+
     // Note: at some point, nopt needs to know about the generator options, the
     // one that will be triggered by the below args. Maybe the nopt parsing
     // should be done internally, from the args.