fix: narrow parse and prefetch exception handling

src/scribae/feedback.py

@@ -9,6 +9,7 @@
 from typing import Any, Literal, cast
 
 import frontmatter
+import yaml
 from pydantic import BaseModel, ConfigDict, ValidationError, field_validator
 from pydantic_ai import Agent, NativeOutput, UnexpectedModelBehavior
 from pydantic_ai.settings import ModelSettings
@@ -603,7 +604,7 @@ def _load_body(body_path: Path, *, max_chars: int) -> BodyDocument:
         raise FeedbackFileError(f"Draft file not found: {body_path}") from exc
     except OSError as exc:  # pragma: no cover - surfaced by CLI
         raise FeedbackFileError(f"Unable to read draft: {exc}") from exc
-    except Exception as exc:  # pragma: no cover - parsing errors
+    except (yaml.YAMLError, TypeError, ValueError) as exc:  # pragma: no cover - parsing errors
         raise FeedbackFileError(f"Unable to parse draft {body_path}: {exc}") from exc
 
     metadata = dict(post.metadata or {})

src/scribae/io_utils.py

@@ -6,6 +6,7 @@
 from typing import Any
 
 import frontmatter
+import yaml
 
 # Type alias for verbose output callbacks used across modules.
 Reporter = Callable[[str], None] | None
@@ -38,7 +39,7 @@ def load_note(note_path: Path, *, max_chars: int) -> NoteDetails:
         raise FileNotFoundError(f"Note file not found: {note_path}") from exc
     except OSError as exc:  # pragma: no cover - surfaced to CLI
         raise OSError(f"Unable to read note {note_path}: {exc}") from exc
-    except Exception as exc:  # pragma: no cover - parsing errors
+    except (yaml.YAMLError, TypeError, ValueError) as exc:  # pragma: no cover - parsing errors
         raise ValueError(f"Unable to parse note {note_path}: {exc}") from exc
 
     metadata = dict(post.metadata or {})

src/scribae/language.py

@@ -131,7 +131,7 @@ def _detect_language(text: str, language_detector: Callable[[str], str] | None)
         return normalize_language(detector(sample))
     except LanguageResolutionError:
         raise
-    except Exception as exc:
+    except (AttributeError, TypeError, ValueError, RuntimeError) as exc:
         raise LanguageResolutionError(f"Language detection failed: {exc}") from exc
 
 
@@ -143,7 +143,7 @@ def _default_language_detector() -> Callable[[str], str]:
 
     try:
         detector = LanguageDetectorBuilder.from_all_languages().build()
-    except Exception as exc:  # pragma: no cover - defensive fallback
+    except (AttributeError, TypeError, ValueError, RuntimeError) as exc:  # pragma: no cover - defensive fallback
         return _naive_detector(exc)
 
     def _detect(sample: str) -> str:

src/scribae/meta.py

@@ -339,7 +339,7 @@ def _load_body(body_path: Path, *, max_chars: int) -> BodyDocument:
         raise MetaFileError(f"Body file not found: {body_path}") from exc
     except OSError as exc:  # pragma: no cover - surfaced by CLI
         raise MetaFileError(f"Unable to read body: {exc}") from exc
-    except Exception as exc:  # pragma: no cover - parsing errors
+    except (yaml.YAMLError, TypeError, ValueError) as exc:  # pragma: no cover - parsing errors
         raise MetaFileError(f"Unable to parse body {body_path}: {exc}") from exc
 
     metadata = dict(post.metadata or {})

src/scribae/translate_cli.py

@@ -24,6 +24,7 @@
     TranslationConfig,
     TranslationPipeline,
 )
+from scribae.translate.postedit import PostEditAborted
 
 translate_app = typer.Typer()
 
@@ -60,7 +61,6 @@ def _configure_library_logging() -> None:
         pass
 
 
-
 def _load_glossary(path: Path | None) -> dict[str, str]:
     if path is None:
         return {}
@@ -284,7 +284,7 @@ def translate(
             if reporter:
                 reporter("Fetching post-edit language model...")
             posteditor.prefetch_language_model()
-    except Exception as exc:
+    except (PostEditAborted, RuntimeError) as exc:
         if not prefetch_only and "nllb" in cfg.mt_backend:
             secho_info(
                 "Primary MT model prefetch failed; falling back to NLLB.",
@@ -295,7 +295,7 @@ def translate(
             steps = registry.route(resolved_src, tgt, allow_pivot=False, backend=cfg.mt_backend)
             try:
                 mt.prefetch(steps)
-            except Exception as fallback_exc:
+            except RuntimeError as fallback_exc:
                 typer.secho(str(fallback_exc), err=True, fg=typer.colors.RED)
                 raise typer.Exit(4) from fallback_exc
         else:

tests/unit/io_utils_test.py

@@ -1,6 +1,11 @@
 from __future__ import annotations
 
-from scribae.io_utils import Reporter, truncate
+from pathlib import Path
+
+import pytest
+import yaml
+
+from scribae.io_utils import Reporter, load_note, truncate
 
 
 class TestTruncate:
@@ -76,3 +81,32 @@ def dummy(msg: str) -> None:
         r2: Reporter = None
         assert callable(r1)
         assert r2 is None
+
+
+class TestLoadNoteErrors:
+    def test_load_note_wraps_value_error_as_parse_error(self, monkeypatch: pytest.MonkeyPatch) -> None:
+        def _boom(_path: Path) -> None:
+            raise ValueError("invalid frontmatter")
+
+        monkeypatch.setattr("scribae.io_utils.frontmatter.load", _boom)
+
+        with pytest.raises(ValueError, match="Unable to parse note"):
+            load_note(Path("note.md"), max_chars=100)
+
+    def test_load_note_wraps_yaml_error_as_parse_error(self, monkeypatch: pytest.MonkeyPatch) -> None:
+        def _boom(_path: Path) -> None:
+            raise yaml.YAMLError("bad yaml")
+
+        monkeypatch.setattr("scribae.io_utils.frontmatter.load", _boom)
+
+        with pytest.raises(ValueError, match="Unable to parse note"):
+            load_note(Path("note.md"), max_chars=100)
+
+    def test_load_note_does_not_mask_unexpected_runtime_errors(self, monkeypatch: pytest.MonkeyPatch) -> None:
+        def _boom(_path: Path) -> None:
+            raise RuntimeError("unexpected parser failure")
+
+        monkeypatch.setattr("scribae.io_utils.frontmatter.load", _boom)
+
+        with pytest.raises(RuntimeError, match="unexpected parser failure"):
+            load_note(Path("note.md"), max_chars=100)

tests/unit/translate_cli_test.py

@@ -453,6 +453,30 @@ def _raise(self: object, steps: list[object]) -> None:
     assert "prefetch failed" in ansi_stripped
 
 
+def test_translate_prefetch_does_not_swallow_unexpected_errors(
+    monkeypatch: pytest.MonkeyPatch,
+    stub_translation_components: dict[str, Any],
+) -> None:
+    def _raise(self: object, steps: list[object]) -> None:
+        raise ValueError("unexpected")
+
+    monkeypatch.setattr("scribae.translate_cli.MTTranslator.prefetch", _raise)
+
+    result = runner.invoke(
+        app,
+        [
+            "translate",
+            "--src",
+            "en",
+            "--tgt",
+            "de",
+            "--prefetch-only",
+        ],
+    )
+
+    assert isinstance(result.exception, ValueError)
+
+
 def test_translate_warns_on_source_mismatch(
     monkeypatch: pytest.MonkeyPatch,
     stub_translation_components: dict[str, Any],