Optimizing Android Test Runs: Parsing Test Names and Implementing Parallelization

Fastfile

default_platform :android
skip_docs

lane :build do
  gradle(tasks: ['assembleDebugAndroidTest', 'assembleDebug'])
end

lane :test do
  install_test_services
  install_test_parser

  apk_path = "path/to/app.apk"
  test_apk_path = "path/to/test.apk"

  sh("adb install -r #{apk_path}")
  sh("adb install -r #{test_apk_path}")

  current_test_batch = batch_tests(
    batch_number: options[:batch_number],
    batch_count: options[:batch_count],
    test_apk_path: test_apk_path
  )

  app_package_name = 'com.example'
  test_package_name = "#{app_package_name}.test"
  test_runner_package_name = 'androidx.test.runner.AndroidJUnitRunner'
  test_orchestrator_package_name = 'androidx.test.orchestrator/.AndroidTestOrchestrator'
  androidx_test_services_path = sh('adb shell pm path androidx.test.services').strip

  result = sh(
    "adb shell 'CLASSPATH=#{androidx_test_services_path}' " \
    'app_process / androidx.test.services.shellexecutor.ShellMain am instrument -w '\
    '-e clearPackageData true ' \
    "-e targetInstrumentation #{test_package_name}/#{test_runner_package_name} " \
    "-e class #{current_test_batch.join(',')} #{test_orchestrator_package_name}"
  )
  UI.user_error!('Tests have failed!') if result.include?('Failures')
end

lane :batch_tests do |options|
  current_batch = []
  if options[:batch_number] && options[:batch_count]
    sh("java -jar test-parser.jar #{options[:test_apk_path]} ./")
    test_names = File.read('AllTests.txt').split
    current_batch = test_names.each_slice((test_names.size.to_f / options[:batch_count].to_i).ceil).to_a[options[:batch_number].to_i]
  end
  UI.success("Contents of the current batch: #{current_batch}")
  current_batch
end

lane :install_test_services do
  device_api_level = sh('adb shell getprop ro.build.version.sdk').strip.to_i
  force_queryable = device_api_level >= 30 ? '--force-queryable' : ''
  version = '1.5.0'

  output = 'test-services.apk'
  url = "https://dl.google.com/dl/android/maven2/androidx/test/services/test-services/#{version}/test-services-#{version}.apk"
  sh("wget -O #{output} '#{url}' 2>/dev/null") unless File.exist?(output)
  sh("adb install #{force_queryable} -r #{output}")

  output = 'orchestrator.apk'
  url = "https://dl.google.com/dl/android/maven2/androidx/test/services/orchestrator/#{version}/orchestrator-#{version}.apk"
  sh("wget -O #{output} '#{url}' 2>/dev/null") unless File.exist?(output)
  sh("adb install #{force_queryable} -r #{output}")
end