fix(build): Remove explicit .coffee extensions in UpdateThreadsTask, update linter to check for these

build/Gruntfile.coffee

@@ -199,6 +199,19 @@ module.exports = (grunt) ->
 
     peg: pegConfig
 
+    nylaslint:
+      src: [
+        'internal_packages/**/*.cjsx'
+        'internal_packages/**/*.coffee'
+        'dot-nylas/**/*.coffee'
+        'exports/**/*.coffee'
+        'src/**/*.coffee'
+        'src/**/*.cjsx'
+        'spec/*.coffee'
+        'spec-nylas/*.cjsx'
+        'spec-nylas/*.coffee'
+      ]
+
     coffeelint:
       options:
         configFile: 'coffeelint.json'
@@ -303,7 +316,7 @@ module.exports = (grunt) ->
           failOnError: false
 
   grunt.registerTask('compile', ['coffee', 'cjsx', 'prebuild-less', 'cson', 'peg'])
-  grunt.registerTask('lint', ['coffeelint', 'csslint', 'lesslint'])
+  grunt.registerTask('lint', ['coffeelint', 'csslint', 'lesslint', 'nylaslint'])
   grunt.registerTask('test', ['shell:kill-atom', 'run-edgehill-specs'])
   grunt.registerTask('docs', ['build-docs', 'render-docs'])
 

build/tasks/nylaslint-task.coffee

@@ -0,0 +1,21 @@
+path = require 'path'
+fs = require 'fs-plus'
+
+module.exports = (grunt) ->
+  {spawn} = require('./task-helpers')(grunt)
+
+  grunt.registerMultiTask 'nylaslint', 'Check requires for file extensions compiled away', ->
+    done = @async()
+    regex = /require ['"].*\.(coffee|cjsx|jsx)['"]/i
+
+    for fileset in @files
+      grunt.log.writeln('Nylinting ' + fileset.src.length + ' files.')
+
+      # file.src is the list of all matching file names.
+      for f in fileset.src
+        content = fs.readFileSync(f, encoding:'utf8')
+        if regex.test(content)
+          done(new Error("#{f} contains a bad require including an coffee / cjsx / jsx extension. Remove the extension!"))
+          return
+
+    done(null)

src/flux/tasks/update-threads-task.coffee

@@ -1,6 +1,6 @@
 _ = require 'underscore'
-Thread = require '../models/thread.coffee'
-Message = require '../models/message.coffee'
+Thread = require '../models/thread'
+Message = require '../models/message'
 NylasAPI = require '../nylas-api'
 DatabaseStore = require '../stores/database-store'
 UpdateNylasObjectsTask = require './update-nylas-objects-task'