add check-yaml-sorted script and tests

tests/check_yaml_sorted_test.py

@@ -0,0 +1,102 @@
+from __future__ import annotations
+
+import yaml
+
+from pre_commit_hooks.check_yaml_sorted import is_sorted
+
+
+def test_sort_list_by_items():
+    assert is_sorted(['a'])
+    assert is_sorted(['a', 'b'])
+    assert not is_sorted(['b', 'a'])
+    assert is_sorted(['a', 'b', 'c', 'd'])
+    assert not is_sorted(['a', 'b', 'd', 'c'])
+
+
+def test_sort_dicts_by_keys():
+    assert is_sorted({'a': 1, 'b': ['nested', 'list'], 'c': 3})
+    assert not is_sorted({'a': 1, 'c': ['nested', 'list'], 'b': 3})
+
+
+_list_dicts_first_key_sorted = """
+-   first_dict:
+        some: stuff
+-   second_dict:
+        other: stuff
+-   third_dict:
+        even: more stuff
+"""
+
+_list_dicts_first_key_unsorted = """
+-   second_dict:
+        some: stuff
+-   first_dict:
+        other: stuff
+-   third_dict:
+        even: more stuff
+"""
+
+
+def test_sort_list_of_dicts_by_first_key():
+    assert is_sorted(yaml.safe_load(_list_dicts_first_key_sorted))
+    assert not is_sorted(yaml.safe_load(_list_dicts_first_key_unsorted))
+
+
+_sorted_yaml = """
+-   id: check-builtin-literals
+-   id: check-case-conflict
+-   id: check-docstring-first
+"""
+
+_sorted_yaml_long = """
+-   id: check-builtin-literals
+    name: check builtin type constructor use
+    description: requires literal syntax when initializing empty or zero....
+    entry: check-builtin-literals
+    language: python
+    types: [python]
+-   id: check-case-conflict
+    name: check for case conflicts
+    description: checks for files that would conflict in case-insensitive...
+    entry: check-case-conflict
+    language: python
+-   id: check-docstring-first
+    name: check docstring is first
+    description: checks a common error of defining a docstring after code.
+    entry: check-docstring-first
+    language: python
+    types: [python]
+"""
+
+_unsorted_yaml = """
+-   id: check-builtin-literals
+-   id: check-docstring-first
+-   id: check-case-conflict
+"""
+
+_unsorted_yaml_long = """
+-   id: check-builtin-literals
+    name: check builtin type constructor use
+    description: requires literal syntax when initializing empty or zero....
+    entry: check-builtin-literals
+    language: python
+    types: [python]
+-   id: check-docstring-first
+    name: check docstring is first
+    description: checks a common error of defining a docstring after code.
+    entry: check-docstring-first
+    language: python
+    types: [python]
+-   id: check-case-conflict
+    name: check for case conflicts
+    description: checks for files that would conflict in case-insensitive...
+    entry: check-case-conflict
+    language: python
+"""
+
+
+def test_sort_list_of_dicts_same_first_key_by_val():
+    assert is_sorted(yaml.safe_load(_sorted_yaml))
+    assert is_sorted(yaml.safe_load(_sorted_yaml_long))
+    assert not is_sorted(yaml.safe_load(_unsorted_yaml))
+    assert not is_sorted(yaml.safe_load(_unsorted_yaml_long))