Moving from aspy.yaml to ruamel.yaml in order to preserve comments when using autoupdate - fixes #210

pre_commit/clientlib/validate_base.py

@@ -9,9 +9,9 @@ import sys
 import jsonschema
 import jsonschema.exceptions
 import pkg_resources
-import yaml
 
 from pre_commit.jsonschema_extensions import apply_defaults
+from pre_commit.yaml import yaml_load
 
 
 def is_regex_valid(regex):
@@ -36,7 +36,7 @@ def get_validator(
             the object read from the file.  The function should either raise
             exception_type on failure.
     """
-    def validate(filename, load_strategy=yaml.load):
+    def validate(filename, load_strategy=yaml_load):
         if not os.path.exists(filename):
             raise exception_type('File {} does not exist'.format(filename))
 

pre_commit/commands/autoupdate.py

@@ -4,9 +4,6 @@ from __future__ import unicode_literals
 import logging
 import sys
 
-from aspy.yaml import ordered_dump
-from aspy.yaml import ordered_load
-
 import pre_commit.constants as C
 from pre_commit.clientlib.validate_config import CONFIG_JSON_SCHEMA
 from pre_commit.clientlib.validate_config import is_local_hooks
@@ -18,6 +15,8 @@ from pre_commit.repository import Repository
 from pre_commit.util import CalledProcessError
 from pre_commit.util import cmd_output
 from pre_commit.util import cwd
+from pre_commit.yaml import yaml_dump
+from pre_commit.yaml import yaml_load
 
 
 logger = logging.getLogger('pre_commit')
@@ -79,7 +78,7 @@ def autoupdate(runner):
 
     input_configs = load_config(
         runner.config_file_path,
-        load_strategy=ordered_load,
+        load_strategy=yaml_load,
     )
 
     for repo_config in input_configs:
@@ -111,7 +110,7 @@ def autoupdate(runner):
     if changed:
         with open(runner.config_file_path, 'w') as config_file:
             config_file.write(
-                ordered_dump(
+                yaml_dump(
                     remove_defaults(output_configs, CONFIG_JSON_SCHEMA),
                     **C.YAML_DUMP_KWARGS
                 )

pre_commit/yaml.py

@@ -0,0 +1,11 @@
+from ruamel import yaml
+
+
+def yaml_dump(obj, **kwargs):
+    "Ensure order & comments preservation"
+    return yaml.dump(obj, Dumper=yaml.RoundTripDumper, **kwargs)
+
+
+def yaml_load(content):
+    "Ensure order & comments preservation"
+    return yaml.load(content, Loader=yaml.RoundTripLoader)

setup.py

@@ -37,12 +37,12 @@ setup(
         ]
     },
     install_requires=[
-        'aspy.yaml',
         'cached-property',
         'jsonschema',
         'nodeenv>=0.11.1',
         'pyterminalsize',
         'pyyaml',
+        'ruamel.yaml',
         'virtualenv',
     ],
     entry_points={

testing/fixtures.py

@@ -5,9 +5,6 @@ import contextlib
 import io
 import os.path
 
-from aspy.yaml import ordered_dump
-from aspy.yaml import ordered_load
-
 import pre_commit.constants as C
 from pre_commit.clientlib.validate_config import CONFIG_JSON_SCHEMA
 from pre_commit.clientlib.validate_config import validate_config_extra
@@ -16,6 +13,8 @@ from pre_commit.jsonschema_extensions import apply_defaults
 from pre_commit.ordereddict import OrderedDict
 from pre_commit.util import cmd_output
 from pre_commit.util import cwd
+from pre_commit.yaml import yaml_dump
+from pre_commit.yaml import yaml_load
 from testing.util import copy_tree_to_path
 from testing.util import get_head_sha
 from testing.util import get_resource_path
@@ -41,10 +40,10 @@ def make_repo(tempdir_factory, repo_source):
 def modify_manifest(path):
     """Modify the manifest yielded by this context to write to hooks.yaml."""
     manifest_path = os.path.join(path, C.MANIFEST_FILE)
-    manifest = ordered_load(io.open(manifest_path).read())
+    manifest = yaml_load(io.open(manifest_path).read())
     yield manifest
     with io.open(manifest_path, 'w') as manifest_file:
-        manifest_file.write(ordered_dump(manifest, **C.YAML_DUMP_KWARGS))
+        manifest_file.write(yaml_dump(manifest, **C.YAML_DUMP_KWARGS))
     cmd_output('git', 'commit', '-am', 'update hooks.yaml', cwd=path)
 
 
@@ -54,10 +53,10 @@ def modify_config(path='.', commit=True):
     .pre-commit-config.yaml
     """
     config_path = os.path.join(path, C.CONFIG_FILE)
-    config = ordered_load(io.open(config_path).read())
+    config = yaml_load(io.open(config_path).read())
     yield config
     with io.open(config_path, 'w', encoding='UTF-8') as config_file:
-        config_file.write(ordered_dump(config, **C.YAML_DUMP_KWARGS))
+        config_file.write(yaml_dump(config, **C.YAML_DUMP_KWARGS))
     if commit:
         cmd_output('git', 'commit', '-am', 'update config', cwd=path)
 
@@ -99,7 +98,7 @@ def write_config(directory, config):
         assert type(config) is OrderedDict
         config = [config]
     with io.open(os.path.join(directory, C.CONFIG_FILE), 'w') as config_file:
-        config_file.write(ordered_dump(config, **C.YAML_DUMP_KWARGS))
+        config_file.write(yaml_dump(config, **C.YAML_DUMP_KWARGS))
 
 
 def add_config_to_repo(git_path, config):

tests/clientlib/validate_base_test.py

@@ -1,10 +1,12 @@
 from __future__ import unicode_literals
 
+import sys
+
 import pytest
-from aspy.yaml import ordered_load
 
 from pre_commit.clientlib.validate_base import get_validator
 from pre_commit.ordereddict import OrderedDict
+from pre_commit.yaml import yaml_load
 from testing.util import get_resource_path
 
 
@@ -68,6 +70,11 @@ def test_returns_object_after_validating(noop_validator):
 def test_load_strategy(noop_validator):
     ret = noop_validator(
         get_resource_path('ordering_data_test.yaml'),
-        load_strategy=ordered_load,
+        load_strategy=yaml_load,
     )
-    assert type(ret) is OrderedDict
+    if sys.version_info[0] < 3:
+        # ruamel.yaml uses a different implementation for Python < 3
+        from ruamel.yaml.compat import ordereddict
+        assert isinstance(ret, ordereddict)
+    else:
+        assert isinstance(ret, OrderedDict)