Clean up merge_target_files.py.

- Removes functions that can be replaced with one-line external methods
- Moves read_config_list to common alongside similar methods LoadDictionaryFrom*
- Runs pyformat on merge_target_files.py

Bug: 137853921
Test: python -m unittest test_merge_target_files
Test: Using merge_target_files.py to create a merged build, & booting.
Change-Id: I833c1086db41e1374057cc7447fc50d1915734a7
diff --git a/tools/releasetools/merge_target_files.py b/tools/releasetools/merge_target_files.py
index f73bae1..7343f38 100755
--- a/tools/releasetools/merge_target_files.py
+++ b/tools/releasetools/merge_target_files.py
@@ -13,9 +13,8 @@
 # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 # License for the specific language governing permissions and limitations under
 # the License.
-
-"""
-This script merges two partial target files packages.
+#
+"""This script merges two partial target files packages.
 
 One package contains framework files, and the other contains vendor files.
 It produces a complete target files package that can be used to generate an
@@ -239,8 +238,7 @@
   # Filter the extract_item_list to remove any items that do not exist in the
   # zip file. Otherwise, the extraction step will fail.
 
-  with zipfile.ZipFile(
-      target_files, allowZip64=True) as target_files_zipfile:
+  with zipfile.ZipFile(target_files, allowZip64=True) as target_files_zipfile:
     target_files_namelist = target_files_zipfile.namelist()
 
   filtered_extract_item_list = []
@@ -282,21 +280,6 @@
       shutil.copyfile(original_file_path, copied_file_path)
 
 
-def read_config_list(config_file_path):
-  """Reads a config file into a list of strings.
-
-  Expects the file to be newline-separated.
-
-  Args:
-    config_file_path: The path to the config file to open and read.
-
-  Returns:
-    The list of strings in the config file.
-  """
-  with open(config_file_path) as config_file:
-    return config_file.read().splitlines()
-
-
 def validate_config_lists(framework_item_list, framework_misc_info_keys,
                           vendor_item_list):
   """Performs validations on the merge config lists.
@@ -748,14 +731,14 @@
 
   find_command = ['find', target_path] + (extra_args or [])
   find_process = common.Run(find_command, stdout=subprocess.PIPE, verbose=False)
-  return common.RunAndCheckOutput(['sort'], stdin=find_process.stdout,
+  return common.RunAndCheckOutput(['sort'],
+                                  stdin=find_process.stdout,
                                   verbose=False)
 
 
 def create_merged_package(temp_dir, framework_target_files, framework_item_list,
                           vendor_target_files, vendor_item_list,
-                          framework_misc_info_keys,
-                          rebuild_recovery):
+                          framework_misc_info_keys, rebuild_recovery):
   """Merges two target files packages into one target files structure.
 
   Args:
@@ -875,8 +858,7 @@
   """
   # Create super_empty.img using the merged misc_info.txt.
 
-  misc_info_txt = os.path.join(target_dir, 'META',
-                               'misc_info.txt')
+  misc_info_txt = os.path.join(target_dir, 'META', 'misc_info.txt')
 
   use_dynamic_partitions = common.LoadDictionaryFromFile(misc_info_txt).get(
       'use_dynamic_partitions')
@@ -885,8 +867,7 @@
     raise ValueError(
         'Building super_empty.img requires use_dynamic_partitions=true.')
   elif use_dynamic_partitions == 'true':
-    super_empty_img = os.path.join(target_dir, 'IMAGES',
-                                   'super_empty.img')
+    super_empty_img = os.path.join(target_dir, 'IMAGES', 'super_empty.img')
     build_super_image_args = [
         misc_info_txt,
         super_empty_img,
@@ -898,21 +879,6 @@
       shutil.copyfile(super_empty_img, output_super_empty)
 
 
-def create_img_archive(source_path, target_path):
-  """Creates IMG archive in target path from source package.
-
-  Args:
-    source_path: Path of the source package to be packed.
-    target_path: Create IMG package from the source package.
-  """
-
-  img_from_target_files_args = [
-      source_path,
-      target_path,
-  ]
-  img_from_target_files.main(img_from_target_files_args)
-
-
 def create_target_files_archive(output_file, source_dir, temp_dir):
   """Creates archive from target package.
 
@@ -923,13 +889,12 @@
   """
   output_target_files_list = os.path.join(temp_dir, 'output.list')
   output_zip = os.path.abspath(output_file)
-  output_target_files_meta_dir = os.path.join(source_dir,
-                                              'META')
+  output_target_files_meta_dir = os.path.join(source_dir, 'META')
 
   meta_content = files_from_path(output_target_files_meta_dir)
-  other_content = files_from_path(source_dir,
-                                  ['-path', output_target_files_meta_dir,
-                                   '-prune', '-o', '-print'])
+  other_content = files_from_path(
+      source_dir,
+      ['-path', output_target_files_meta_dir, '-prune', '-o', '-print'])
 
   with open(output_target_files_list, 'w') as f:
     f.write(meta_content)
@@ -953,20 +918,6 @@
   return output_zip
 
 
-def create_ota_package(zip_package, output_ota):
-  """Creates OTA package from archived package.
-
-  Args:
-    zip_package: The name of the zip archived package.
-    output_ota: The name of the output zip archive ota package.
-  """
-  ota_from_target_files_args = [
-      zip_package,
-      output_ota,
-  ]
-  ota_from_target_files.main(ota_from_target_files_args)
-
-
 def merge_target_files(temp_dir, framework_target_files, framework_item_list,
                        framework_misc_info_keys, vendor_target_files,
                        vendor_item_list, output_target_files, output_dir,
@@ -1024,7 +975,7 @@
   if output_img:
     # Create the IMG package from the merged target files (before zipping, in
     # order to avoid an unnecessary unzip and copy).
-    create_img_archive(output_target_files_temp_dir, output_img)
+    img_from_target_files.main([output_target_files_temp_dir, output_img])
 
   # Finally, create the output target files zip archive and/or copy the
   # output items to the output target files directory.
@@ -1042,7 +993,7 @@
   # Create the OTA package from the merged target files package.
 
   if output_ota:
-    create_ota_package(output_zip, output_ota)
+    ota_from_target_files.main([output_zip, output_ota])
 
 
 def call_func_with_temp_dir(func, keep_tmp):
@@ -1095,10 +1046,8 @@
     elif o == '--framework-item-list':
       OPTIONS.framework_item_list = a
     elif o == '--system-misc-info-keys':
-      logger.warning(
-          '--system-misc-info-keys has been renamed to '
-          '--framework-misc-info-keys'
-      )
+      logger.warning('--system-misc-info-keys has been renamed to '
+                     '--framework-misc-info-keys')
       OPTIONS.framework_misc_info_keys = a
     elif o == '--framework-misc-info-keys':
       OPTIONS.framework_misc_info_keys = a
@@ -1167,23 +1116,23 @@
     sys.exit(1)
 
   if OPTIONS.framework_item_list:
-    framework_item_list = read_config_list(OPTIONS.framework_item_list)
+    framework_item_list = common.LoadListFromFile(OPTIONS.framework_item_list)
   else:
     framework_item_list = DEFAULT_FRAMEWORK_ITEM_LIST
 
   if OPTIONS.framework_misc_info_keys:
-    framework_misc_info_keys = read_config_list(
+    framework_misc_info_keys = common.LoadListFromFile(
         OPTIONS.framework_misc_info_keys)
   else:
     framework_misc_info_keys = DEFAULT_FRAMEWORK_MISC_INFO_KEYS
 
   if OPTIONS.vendor_item_list:
-    vendor_item_list = read_config_list(OPTIONS.vendor_item_list)
+    vendor_item_list = common.LoadListFromFile(OPTIONS.vendor_item_list)
   else:
     vendor_item_list = DEFAULT_VENDOR_ITEM_LIST
 
   if OPTIONS.output_item_list:
-    output_item_list = read_config_list(OPTIONS.output_item_list)
+    output_item_list = common.LoadListFromFile(OPTIONS.output_item_list)
   else:
     output_item_list = None