some refactoring

Author: contrust

cvs/diff.py

@@ -63,4 +63,4 @@ def get_commit_hash_by_ref_name(name: str) -> str:
     if is_tag_exist(name):
         commit_hash = get_tag_commit_hash(name)
         return commit_hash
-    return None
+    return None

tests/test_commit.py

@@ -1,5 +1,5 @@
-from cvs.modify import add
 from cvs.commit import *
+from cvs.modify import add
 
 
 def test_commit_file_is_created_after_committing(create_two_files):
@@ -9,7 +9,7 @@ def test_commit_file_is_created_after_committing(create_two_files):
 
 
 def test_commit_file_content_matches_regex(create_two_files,
-                                                create_dir_with_two_files):
+                                           create_dir_with_two_files):
     add('.')
     commit_hash = commit('')
     commit_file_content = (commits_path / commit_hash).read_text()

tests/test_diff.py

@@ -1,6 +1,6 @@
 from unittest.mock import patch
 
-from build.lib.cvs.commit import commit
+from cvs.commit import commit
 from cvs.diff import *
 from cvs.modify import add
 from cvs.config import repository_path