fastlane: Snapshot: UITest ok on Xcode but failed on snapshot

New Issue Checklist

• Updated fastlane to the latest version
• I have read the Contribution Guidelines

Issue Description

I was using successfully snapshot to take screenshots of all device sizes for both en and fr locale. I have a single UI test case testTakeScreenshots which basically go through the app and take 4 screenshots. This tests pass successfully when running on Xcode but this fails running with snapshot and I cannot figure out why.

Complete output when running fastlane, including the stack trace and command used

testTakeScreenshots, UI Testing Failure - Failure getting snapshot Error Domain=XCTestManagerErrorDomain Code=9 "Error -25204 getting snapshot for element <AXUIElement 0x7fca0ae146f0> {pid=28169}" UserInfo={NSLocalizedDescription=Error -25204 getting snapshot for element <AXUIElement 0x7fca0ae146f0> {pid=28169}}
<unknown>:0

     Executed 1 test, with 1 failure (0 unexpected) in 6.084 (6.087) seconds

ERROR [2016-05-17 21:52:09.52]: Exit status: 65
ERROR [2016-05-17 21:52:09.53]: Tests failed - check out the log above
ERROR [2016-05-17 21:52:09.53]: Backtrace:
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/fastlane_core-0.41.3/lib/fastlane_core/ui/interface.rb:139:in `user_error!'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/fastlane_core-0.41.3/lib/fastlane_core/ui/ui.rb:14:in `method_missing'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/lib/snapshot/error_handler.rb:10:in `handle_test_error'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/lib/snapshot/runner.rb:172:in `block in launch'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/fastlane_core-0.41.3/lib/fastlane_core/command_executor.rb:85:in `call'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/fastlane_core-0.41.3/lib/fastlane_core/command_executor.rb:85:in `execute'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/lib/snapshot/runner.rb:166:in `launch'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/lib/snapshot/runner.rb:66:in `run_for_device_and_language'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/lib/snapshot/runner.rb:45:in `block (3 levels) in work'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/lib/snapshot/runner.rb:37:in `each'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/lib/snapshot/runner.rb:37:in `block (2 levels) in work'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/lib/snapshot/runner.rb:36:in `each'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/lib/snapshot/runner.rb:36:in `block in work'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/lib/snapshot/runner.rb:35:in `each'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/lib/snapshot/runner.rb:35:in `work'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/bin/snapshot:36:in `block (2 levels) in run'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/commander-4.3.5/lib/commander/command.rb:178:in `call'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/commander-4.3.5/lib/commander/command.rb:178:in `call'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/commander-4.3.5/lib/commander/command.rb:153:in `run'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/commander-4.3.5/lib/commander/runner.rb:428:in `run_active_command'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/fastlane_core-0.41.3/lib/fastlane_core/ui/fastlane_runner.rb:23:in `run!'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/commander-4.3.5/lib/commander/delegates.rb:15:in `run!'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/bin/snapshot:96:in `run'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/bin/snapshot:110:in `<top (required)>'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/bin/snapshot:23:in `load'
    /Users/GUL/.rvm/rubies/ruby-2.1.3/bin/snapshot:23:in `<main>'
    /Users/GUL/.rvm/gems/ruby-2.1.3/bin/ruby_executable_hooks:15:in `eval'
    /Users/GUL/.rvm/gems/ruby-2.1.3/bin/ruby_executable_hooks:15:in `<main>'

+----------+---------+
|  snapshot results  |
+----------+---------+
| Device   | fr-FR   |
+----------+---------+
| iPhone 6 |  ❌      |
+----------+---------+

Successfully submitted a crash report. If this is a problem with one of the tools specifically,
please submit an issue on GitHub and attach the following number to it: 'fd9b91c7c71867c72260d25d90fbb7a7'
The crash report has been stored locally '/tmp/sentry_fd9b91c7c71867c72260d25d90fbb7a7.json'
/Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/lib/snapshot/runner.rb:52:in `work': [!] Tests failed - check out the log above (RuntimeError)
    from /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/bin/snapshot:36:in `block (2 levels) in run'
    from /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/commander-4.3.5/lib/commander/command.rb:178:in `call'
    from /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/commander-4.3.5/lib/commander/command.rb:178:in `call'
    from /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/commander-4.3.5/lib/commander/command.rb:153:in `run'
    from /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/commander-4.3.5/lib/commander/runner.rb:428:in `run_active_command'
    from /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/fastlane_core-0.41.3/lib/fastlane_core/ui/fastlane_runner.rb:23:in `run!'
    from /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/commander-4.3.5/lib/commander/delegates.rb:15:in `run!'
    from /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/bin/snapshot:96:in `run'
    from /Users/GUL/.rvm/rubies/ruby-2.1.3/lib/ruby/gems/2.1.0/gems/snapshot-1.12.2/bin/snapshot:110:in `<top (required)>'
    from /Users/GUL/.rvm/rubies/ruby-2.1.3/bin/snapshot:23:in `load'
    from /Users/GUL/.rvm/rubies/ruby-2.1.3/bin/snapshot:23:in `<main>'
    from /Users/GUL/.rvm/gems/ruby-2.1.3/bin/ruby_executable_hooks:15:in `eval'
    from /Users/GUL/.rvm/gems/ruby-2.1.3/bin/ruby_executable_hooks:15:in `<main>'

Configuration Files

Snapfile:

# A list of devices you want to take the screenshots from
 devices([
   "iPhone 6",
   #"iPhone 6 Plus",
   #"iPhone 5",
   #"iPhone 4s",
 ])

languages([
  #"en-US",
  "fr-FR"
])

# Arguments to pass to the app on launch. See https://github.com/fastlane/snapshot#launch-arguments
# launch_arguments(["-favColor red"])

# The name of the scheme which contains the UI Tests
scheme "usiappUITests"

# Where should the resulting screenshots be stored?
output_directory "./fastlane/screenshots"

clear_previous_screenshots true # remove the '#' to clear all previously generated screenshots before creating new ones

# Choose which project/workspace to use
# project "./Project.xcodeproj"
workspace "./usiapp.xcworkspace"

# For more information about all available options run
# snapshot --help

Environment

fastlane version (run fastlane -v): fastlane 1.89.0

snapshot version snapshot 1.12.2

Do you use bundler to execute fastlane (i.e. bundle exec fastlane)? no

Do you use a Ruby environment manager (e.g. chruby, rbenv, rvm)? no