fix: raise FileAccessError for unreadable files in search_file, skip correctly in search_directory

Author: feryc@hotmail.com

src/search_engine.py

@@ -3,7 +3,7 @@
 
 from .config import config
 from .data_models import SimilarMatch
-from .exceptions import SearchError
+from .exceptions import FileAccessError, SearchError
 from .file_access import read_file_lines
 
 
@@ -183,7 +183,7 @@ def search_file(
     try:
         lines = read_file_lines(file_path)
     except Exception as e:
-        raise SearchError(f"Cannot read {file_path}: {e}") from e
+        raise FileAccessError(f"Cannot read {file_path}: {e}") from e
 
     # Route to appropriate matcher
     if regex:

src/tools.py

@@ -938,7 +938,7 @@ def search_directory(
             matches = search_file(
                 abs_path, pattern, fuzzy, regex, case_sensitive, invert
             )
-        except (OSError, UnicodeDecodeError):
+        except FileAccessError:
             continue  # skip unreadable / binary files silently
 
         files_searched += 1

tests/unit/test_search_engine.py

@@ -9,7 +9,7 @@
 import pytest
 
 from src.data_models import SimilarMatch
-from src.exceptions import SearchError
+from src.exceptions import FileAccessError, SearchError
 from src.search_engine import (
     find_exact_matches,
     find_fuzzy_matches,
@@ -234,11 +234,17 @@ def temp_file(self):
         Path(f.name).unlink(missing_ok=True)
 
     def test_regex_and_fuzzy_error(self, temp_file):
-        """Regex and fuzzy together raises error."""
+        """Regex and fuzzy together raises SearchError."""
         with pytest.raises(SearchError) as exc_info:
             search_file(temp_file, "pattern", fuzzy=True, regex=True)
         assert "Cannot use regex and fuzzy together" in str(exc_info.value)
 
+    def test_search_file_unreadable_raises_file_access_error(self):
+        """Unreadable / nonexistent file raises FileAccessError, not SearchError."""
+        with pytest.raises(FileAccessError) as exc_info:
+            search_file("/nonexistent/path/file.txt", "pattern")
+        assert "Cannot read" in str(exc_info.value)
+
     def test_search_file_exact_mode(self, temp_file):
         """Search with fuzzy=False uses exact matching."""
         matches = search_file(temp_file, "ERROR", fuzzy=False)

tests/unit/test_tools_search_directory.py

@@ -4,7 +4,7 @@
 from pathlib import Path
 from unittest.mock import patch
 
-from src.exceptions import SearchError
+from src.exceptions import FileAccessError, SearchError
 from src.tools import search_directory
 
 # ---------------------------------------------------------------------------
@@ -323,7 +323,7 @@ def test_fuzzy_mode_finds_approximate_match(self, tmp_path: Path) -> None:
 
 class TestSearchDirectoryErrorPaths:
     def test_unreadable_file_is_skipped_silently(self, tmp_path: Path) -> None:
-        """OSError from search_file (unreadable / binary) causes the file to be skipped."""
+        """FileAccessError from search_file (unreadable / binary) causes the file to be skipped."""
         (tmp_path / "good.txt").write_text("needle\n")
         (tmp_path / "bad.txt").write_text("needle\n")
 
@@ -335,7 +335,7 @@ def test_unreadable_file_is_skipped_silently(self, tmp_path: Path) -> None:
         def patched_search(path: str, *args, **kwargs):  # type: ignore[no-untyped-def]
             call_count["n"] += 1
             if "bad.txt" in path:
-                raise OSError("access denied")
+                raise FileAccessError("Cannot read bad.txt: access denied")
             return real_search(path, *args, **kwargs)
 
         with patch("src.tools.search_file", side_effect=patched_search):
@@ -349,13 +349,13 @@ def patched_search(path: str, *args, **kwargs):  # type: ignore[no-untyped-def]
         assert "bad.txt" not in files
 
     def test_files_searched_does_not_count_skipped_files(self, tmp_path: Path) -> None:
-        """Files that throw on search_file are not counted in files_searched."""
+        """Files that raise FileAccessError on search_file are not counted in files_searched."""
         (tmp_path / "a.txt").write_text("x\n")
         (tmp_path / "b.txt").write_text("x\n")
 
         def patched_search(path: str, *args, **kwargs):  # type: ignore[no-untyped-def]
             if "b.txt" in path:
-                raise PermissionError("denied")
+                raise FileAccessError("Cannot read b.txt: denied")
             return []
 
         with patch("src.tools.search_file", side_effect=patched_search):