refactor: update diff messages to constants

These changes replace hardcoded diff messages in the GitOperations class and its tests with constants (BINARY_MESSAGE and DELETED_MESSAGE) for better maintainability and readability.

aicmt/git_operations.py

@@ -15,7 +15,7 @@ class Change(NamedTuple):
     Attributes:
         file: Path to the changed file
         status: Current status of the file ('modified', 'deleted', 'new file', etc.)
-        diff: Actual changes or special messages ('[File deleted]', '[Binary file]')
+        diff: Actual changes or special messages ('[File deleted]', 'BINARY_MESSAGE')
         insertions: Number of inserted lines
         deletions: Number of deleted lines
     """
@@ -120,7 +120,7 @@ def get_unstaged_changes(self) -> List[Change]:
             - status can be one of:
                 "modified", "deleted", "new file", "new file (binary)", "error"
             - diff contains the actual changes or special messages:
-                "[File deleted]", "[Binary file]"
+                DELETED_MESSAGE, BINARY_MESSAGE
 
         Raises:
             IOError: If there is an error reading a file
@@ -176,7 +176,7 @@ def get_staged_changes(self) -> List[Change]:
             - status can be one of:
                 "modified", "deleted", "new file", "new file (binary)", "error"
             - diff contains the actual changes or special messages:
-                "[File deleted]", "[Binary file]"
+                DELETED_MESSAGE, BINARY_MESSAGE
             - insertions and deletions contain the number of added/removed lines
 
         Raises:

tests/test_git_operations.py

@@ -2,7 +2,7 @@
 import pytest
 from git import Repo, InvalidGitRepositoryError, GitCommandError, NoSuchPathError
 from gitdb.exc import BadName
-from aicmt.git_operations import GitOperations
+from aicmt.git_operations import GitOperations, safe_file_operation, FileStatus, BINARY_MESSAGE, DELETED_MESSAGE
 from pathlib import Path
 
 
@@ -89,7 +89,8 @@ def test_stage_files(temp_git_repo):
         # Verify that the file is correctly staged
         assert "stage_test.txt" not in untracked
         # Directly check if the file name is in the index
-        assert any("stage_test.txt" in str(entry) for entry in git_ops.repo.index.entries.keys())
+        assert any("stage_test.txt" in str(entry)
+                   for entry in git_ops.repo.index.entries.keys())
 
         with pytest.raises(ValueError) as excinfo:
             git_ops.stage_files([])
@@ -176,7 +177,7 @@ def test_binary_file_changes(temp_git_repo):
         assert len(changes) == 1
         assert changes[0].file == "binary_file.bin"
         assert changes[0].status == "new file (binary)"
-        assert "[Binary file]" in changes[0].diff
+        assert BINARY_MESSAGE in changes[0].diff
     finally:
         os.chdir(current_dir)
 
@@ -223,7 +224,7 @@ def test_binary_file_decode_error(temp_git_repo):
         assert len(changes) == 1
         assert changes[0].file == "test.bin"
         assert changes[0].status == "new file (binary)"
-        assert changes[0].diff == "[Binary file]"
+        assert changes[0].diff == BINARY_MESSAGE
     finally:
         os.chdir(current_dir)
 
@@ -252,7 +253,7 @@ def test_file_not_found_error(temp_git_repo):
         assert len(matching_changes) == 1
         change = matching_changes[0]
         assert change.status == "deleted"
-        assert change.diff == "[File deleted]"
+        assert change.diff == DELETED_MESSAGE
     finally:
         os.chdir(current_dir)
 
@@ -304,6 +305,7 @@ def test_handle_modified_file_diff_error(temp_git_repo):
 
         # Create a Mock object for Git
         class MockGit:
+
             def diff(self, *args, **kwargs):
                 raise GitCommandError("git diff", 128)
 
@@ -333,7 +335,7 @@ def test_handle_untracked_file_deleted(temp_git_repo):
 
     # Assert the results
     assert status == "deleted"
-    assert content == "[File deleted]"
+    assert content == DELETED_MESSAGE
 
 
 def test_stage_deleted_file(temp_git_repo):
@@ -389,7 +391,8 @@ def test_get_commit_changes(temp_git_repo):
         with open("test4.txt", "w") as f:
             pass  # Empty file
 
-        git_ops.repo.index.add(["test1.txt", "test2.txt", "test3.bin", "test4.txt"])
+        git_ops.repo.index.add(
+            ["test1.txt", "test2.txt", "test3.bin", "test4.txt"])
         git_ops.repo.index.commit("Initial commit")
 
         # Make various changes
@@ -419,10 +422,14 @@ def test_get_commit_changes(temp_git_repo):
         assert len(changes) == 4
 
         # Find changes by filename
-        test1_change = next(change for change in changes if change.file == "test1.txt")
-        test2_change = next(change for change in changes if change.file == "test2.txt")
-        test3_change = next(change for change in changes if change.file == "test3.bin")
-        test5_change = next(change for change in changes if change.file == "test5.txt")
+        test1_change = next(change for change in changes
+                            if change.file == "test1.txt")
+        test2_change = next(change for change in changes
+                            if change.file == "test2.txt")
+        test3_change = next(change for change in changes
+                            if change.file == "test3.bin")
+        test5_change = next(change for change in changes
+                            if change.file == "test5.txt")
 
         # Test modified text file
         assert test1_change.status == "modified"
@@ -432,7 +439,7 @@ def test_get_commit_changes(temp_git_repo):
 
         # Test deleted file
         assert test2_change.status == "deleted"
-        assert "[File deleted]" in test2_change.diff
+        assert DELETED_MESSAGE in test2_change.diff
         assert test2_change.insertions == 0
         assert test2_change.deletions > 0
 
@@ -508,12 +515,14 @@ def test_get_staged_changes(temp_git_repo):
         assert new_file.deletions == 0
 
         # Verify new binary file
-        binary_file = next(c for c in first_changes if c.file == "new_binary.bin")
+        binary_file = next(c for c in first_changes
+                           if c.file == "new_binary.bin")
         assert binary_file.status == "new file (binary)"
-        assert binary_file.diff == "[Binary file]"
+        assert binary_file.diff == BINARY_MESSAGE
 
         # Verify modified file
-        modified_file = next(c for c in second_changes if c.file == "modify.txt")
+        modified_file = next(c for c in second_changes
+                             if c.file == "modify.txt")
         assert modified_file.status == "modified"
         assert "-initial" in modified_file.diff
         assert "+modified" in modified_file.diff
@@ -523,7 +532,7 @@ def test_get_staged_changes(temp_git_repo):
         # Verify deleted file
         deleted_file = next(c for c in third_changes if c.file == "delete.txt")
         assert deleted_file.status == "deleted"
-        assert deleted_file.diff == "[File deleted]"
+        assert deleted_file.diff == DELETED_MESSAGE
         assert deleted_file.insertions == 0
         assert deleted_file.deletions > 0