Auto generate test config files

This change allows one to run atest <module name>. The TradeFed test
config file will be automatically created in testcases directory based
on the settings.

Bug: 69929803, 69932044
Test: m -j NotificationStressTests libminijail_test
add following lines in notificationtests/Android.mk,
before "include $(BUILD_PACKAGE)"
LOCAL_COMPATIBILITY_SUITE := general-test

Change-Id: Ib5e9cd152d957b5d5beb6ed23a899a021a7e06d6
diff --git a/tools/auto_gen_test_config.py b/tools/auto_gen_test_config.py
new file mode 100755
index 0000000..fa018f4
--- /dev/null
+++ b/tools/auto_gen_test_config.py
@@ -0,0 +1,86 @@
+#!/usr/bin/env python
+#
+# Copyright (C) 2017 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""A tool to generate TradeFed test config file.
+"""
+
+import os
+import shutil
+import sys
+from xml.dom.minidom import parse
+
+ATTRIBUTE_LABEL = 'android:label'
+ATTRIBUTE_RUNNER = 'android:name'
+ATTRIBUTE_TARGET_PACKAGE = 'android:targetPackage'
+
+PLACEHOLDER_LABEL = '{LABEL}'
+PLACEHOLDER_MODULE = '{MODULE}'
+PLACEHOLDER_PACKAGE = '{PACKAGE}'
+PLACEHOLDER_RUNNER = '{RUNNER}'
+PLACEHOLDER_TEST_TYPE = '{TEST_TYPE}'
+
+
+def main(argv):
+  """Entry point of auto_gen_test_config.
+
+  Args:
+    argv: A list of arguments.
+  Returns:
+    0 if no error, otherwise 1.
+  """
+  if len(argv) != 4:
+    sys.stderr.write(
+        'Invalid arguements. The script requires 4 arguments for file paths: '
+        'target_config android_manifest empty_config '
+        'instrumentation_test_config_template.\n')
+    return 1
+  target_config = argv[0]
+  android_manifest = argv[1]
+  empty_config = argv[2]
+  instrumentation_test_config_template = argv[3]
+
+  manifest = parse(android_manifest)
+  instrumentation_elements = manifest.getElementsByTagName('instrumentation')
+  if len(instrumentation_elements) != 1:
+    # Failed to locate instrumentation element in AndroidManifest file.
+    # Empty test config file will be created.
+    shutil.copyfile(empty_config, target_config)
+    return 0
+
+  module = os.path.splitext(os.path.basename(target_config))[0]
+  instrumentation = instrumentation_elements[0]
+  if instrumentation.attributes.has_key(ATTRIBUTE_LABEL):
+    label = instrumentation.attributes[ATTRIBUTE_LABEL].value
+  else:
+    label = module
+  runner = instrumentation.attributes[ATTRIBUTE_RUNNER].value
+  package = instrumentation.attributes[ATTRIBUTE_TARGET_PACKAGE].value
+  test_type = ('AndroidJUnitTest' if runner.endswith('.AndroidJUnitRunner')
+               else 'InstrumentationTest')
+
+  with open(instrumentation_test_config_template) as template:
+    config = template.read()
+    config = config.replace(PLACEHOLDER_LABEL, label)
+    config = config.replace(PLACEHOLDER_MODULE, module)
+    config = config.replace(PLACEHOLDER_PACKAGE, package)
+    config = config.replace(PLACEHOLDER_TEST_TYPE, test_type)
+    config = config.replace(PLACEHOLDER_RUNNER, runner)
+    with open(target_config, 'w') as config_file:
+      config_file.write(config)
+  return 0
+
+if __name__ == '__main__':
+  sys.exit(main(sys.argv[1:]))