How does #import work in iOS' UI Automation?

I'm making a small test framework that uses the JavaScript module pattern for UI Automation testing on iOS. However, I seem to be getting odd results based on #import and extending modules.

I have the base test module called Tester-Module.js:

(function() {
  var Tester = this.Tester = {};

  Tester.setUp = function() {
    UIALogger.logMessage('Regular SetUp()');
  }
}).call(this);

If I import this module in my test case, it works fine. Here's the test file tester.js (tester.js is the file I import in Instruments):

#import "./Tester-Module.js"

// Prints 'Regular SetUp()'
Tester.setUp();

However, if I try to extend the Tester-Module.js module in another module file, I cannot reference the Tester object. Tester-Extension.js extends the Tester module defined in Tester-Module.js:

#import "./Tester-Module.js"

// Outputs:
// Exception raised while running script:
// ReferenceError: Can't find variable: Tester\n
Tester.setUp = 开发者_运维百科function() {
  UIALogger.logMessage('Overwritten SetUp()');
}

And the updated test case file tester.js:

#import "./Tester-Extension.js"

// Exception is thrown before this
Tester.setUp();

My hopefully related questions are:

• Why can I not reference the Tester object inside Tester-Extension.js, but can in tester.js?

• What is the #import macro doing?

After some more searching and testing, it looks like using #import in each module file — similar to require in Node.js — is not supported with the UI Automation framework.

The work around is to include a header file that imports every module and then just import that in the test case. Using the example above, the header file would look like:

// Tester-Header.js
#import "./Tester-Module.js"
#import "./Tester-Extension.js"

And the test file would simply import the header file like so:

#import "./Tester-Header.js"

// Prints "Overwritten SetUp()"
Tester.setUp();

The Mother May UI BDD framework has a more extensive example of a header file and importing the header file into a test file. Disclosure: I wrote the framework and originally asked this question in order to make the framework more modular.