Add resolved main path to package cache

build/tasks/compile-packages-slug-task.coffee

@@ -7,7 +7,7 @@ module.exports = (grunt) ->
   {spawn, rm} = require('./task-helpers')(grunt)
 
   grunt.registerTask 'compile-packages-slug', 'Add bundled package metadata information to to the main package.json file', ->
-    appDir = grunt.config.get('atom.appDir')
+    appDir = fs.realpathSync(grunt.config.get('atom.appDir'))
 
     modulesDirectory = path.join(appDir, 'node_modules')
     packages = {}
@@ -29,6 +29,10 @@ module.exports = (grunt) ->
 
       pack = {metadata, keymaps: {}, menus: {}}
 
+      if metadata.main
+        mainPath = require.resolve(path.resolve(moduleDirectory, metadata.main))
+        pack.main = path.relative(appDir, mainPath)
+
       for keymapPath in fs.listSync(path.join(moduleDirectory, 'keymaps'), ['.cson', '.json'])
         relativePath = path.relative(appDir, keymapPath)
         pack.keymaps[relativePath] = CSON.readFileSync(keymapPath)

src/package.coffee

@@ -349,12 +349,19 @@ class Package
   getMainModulePath: ->
     return @mainModulePath if @resolvedMainModulePath
     @resolvedMainModulePath = true
-    mainModulePath =
-      if @metadata.main
-        path.join(@path, @metadata.main)
+
+    if @bundledPackage and packagesCache[@name]?
+      if packagesCache[@name].main
+        @mainModulePath = "#{atom.packages.resourcePath}#{path.sep}#{packagesCache[@name].main}"
       else
-        path.join(@path, 'index')
-    @mainModulePath = fs.resolveExtension(mainModulePath, ["", _.keys(require.extensions)...])
+        @mainModulePath = null
+    else
+      mainModulePath =
+        if @metadata.main
+          path.join(@path, @metadata.main)
+        else
+          path.join(@path, 'index')
+      @mainModulePath = fs.resolveExtension(mainModulePath, ["", _.keys(require.extensions)...])
 
   hasActivationCommands: ->
     for selector, commands of @getActivationCommands()