Cannot debug in Xcode: Debug info from this module will be unavailable in the debugger

It's a bug of Xcode. i am facing the same problem. After some researches i found that this happens because of bad code, especially when you use closures. It is being reported as xcode bug, but there are some ways to fix it. Use print("") for debugging.

The problem was not updating User Header Search Paths with the directory containing module.modulemap.

Here are the instructions, accidentally overlooked, for manual installation:

If you're using Swift, or you want to use modules, drag module.modulemap into your project and update your User Header Search Paths to contain the directory that contains your module map.

The other hiccup was recognizing the correct directory path since we used groups to organize files, not folders.

May someone else benefit from our stupidity! :)

You have to add your modules like Firebase to your test-scheme in your podfile

Cocoapods

source 'https://github.com/CocoaPods/Specs.git'
# Uncomment the next line to define a global platform for your project
 platform :ios, '10.0'

target 'yourApp' do
  # Comment the next line if you're not using Swift and don't want to use dynamic frameworks
  use_frameworks!

  # Pods for yourApp
  pod 'Alamofire', '4.4.0'
  pod 'Firebase', '4.3.0'

  target 'yourAppTests' do
    inherit! :search_paths
    # Pods for testing
    pod 'Firebase', '4.3.0'
  end

end

---

Manualy added

(I'm not 100% sure if this works)

1. Click on you Projekt in Xcode (the very first listpoint in your project)
2. Select at the Targets your test-target (yourAppTests)
3. Search for "other link" at 'Build Settings'
4. add to "Other Linker Flags"
   1. -ObjC
   2. -framework
   3. "GoogleToolboxForMac"
   4. -framework
   5. "nanopb"