Fix catchall exceptions.

Using ValueError for everything caused underlying issues to be
hidden. Now there are explicit classes for each error condition.

src/pycalver/cli.py

@@ -224,7 +224,7 @@ def _bump(cfg: config.Config, new_version: str, allow_dirty: bool = False) -> No
 
     try:
         rewrite.rewrite(new_version, cfg.file_patterns)
-    except ValueError as ex:
+    except Exception as ex:
         log.error(str(ex))
         sys.exit(1)
 
@@ -337,7 +337,7 @@ def bump(
     if dry or verbose >= 2:
         try:
             _print_diff(cfg, new_version)
-        except ValueError as ex:
+        except Exception as ex:
             log.error(str(ex))
             sys.exit(1)
 

src/pycalver/rewrite.py

@@ -41,6 +41,18 @@ def detect_line_sep(content: str) -> str:
         return "\n"
 
 
+class NoPatternMatch(Exception):
+    """Pattern not found in content.
+
+    log.error is used to show error info about the patterns so
+    that users can debug what is wrong with them. The class
+    itself doesn't capture that info. This approach is used so
+    that all patter issues can be shown, rather than bubbling
+    all the way up the stack on the very first pattern with no
+    matches.
+    """
+
+
 def rewrite_lines(
     pattern_strs: typ.List[str], new_version: str, old_lines: typ.List[str]
 ) -> typ.List[str]:
@@ -72,7 +84,7 @@ def rewrite_lines(
             log.error(f"No match for pattern '{non_matched_pattern}'")
             compiled_pattern = patterns._compile_pattern(non_matched_pattern)
             log.error(f"Pattern compiles to regex '{compiled_pattern}'")
-        raise ValueError("Invalid pattern(s)")
+        raise NoPatternMatch("Invalid pattern(s)")
     else:
         return new_lines
 
@@ -110,7 +122,7 @@ def _iter_file_paths(
         file_paths = glob.glob(globstr)
         if not any(file_paths):
             errmsg = f"No files found for path/glob '{globstr}'"
-            raise ValueError(errmsg)
+            raise FileNotFoundError(errmsg)
         for file_path_str in file_paths:
             file_path = pl.Path(file_path_str)
             yield (file_path, pattern_strs)
@@ -188,15 +200,15 @@ def diff(new_version: str, file_patterns: config.PatternsByGlob) -> str:
 
         try:
             rfd = rfd_from_content(pattern_strs, new_version, content)
-        except ValueError:
+        except NoPatternMatch:
             errmsg = f"No patterns matched for '{file_path}'"
-            raise ValueError(errmsg)
+            raise NoPatternMatch(errmsg)
 
         rfd   = rfd._replace(path=str(file_path))
         lines = diff_lines(rfd)
         if len(lines) == 0:
             errmsg = f"No patterns matched for '{file_path}'"
-            raise ValueError(errmsg)
+            raise NoPatternMatch(errmsg)
 
         full_diff += "\n".join(lines) + "\n"
 

src/pycalver/version.py

@@ -183,6 +183,10 @@ PEP440_TAGS: typ.Dict[str, str] = {
 VersionInfoKW = typ.Dict[str, typ.Union[str, int, None]]
 
 
+class PatternError(Exception):
+    pass
+
+
 def _parse_pattern_groups(pattern_groups: typ.Dict[str, str]) -> typ.Dict[str, str]:
     for part_name in pattern_groups.keys():
         is_valid_part_name = (
@@ -190,7 +194,7 @@ def _parse_pattern_groups(pattern_groups: typ.Dict[str, str]) -> typ.Dict[str, s
         )
         if not is_valid_part_name:
             err_msg = f"Invalid part '{part_name}'"
-            raise ValueError(err_msg)
+            raise PatternError(err_msg)
 
     items = [
         (field_name, pattern_groups[part_name])
@@ -203,7 +207,7 @@ def _parse_pattern_groups(pattern_groups: typ.Dict[str, str]) -> typ.Dict[str, s
 
     if any(duplicate_fields):
         err_msg = f"Multiple parts for same field {duplicate_fields}."
-        raise ValueError(err_msg)
+        raise PatternError(err_msg)
 
     return dict(items)
 
@@ -302,7 +306,7 @@ def parse_version_info(version_str: str, pattern: str = "{pycalver}") -> Version
         err_msg = (
             f"Invalid version string '{version_str}' for pattern '{pattern}'/'{regex.pattern}'"
         )
-        raise ValueError(err_msg)
+        raise PatternError(err_msg)
 
     return _parse_version_info(match.groupdict())
 
@@ -322,7 +326,7 @@ def is_valid(version_str: str, pattern: str = "{pycalver}") -> bool:
     try:
         parse_version_info(version_str, pattern)
         return True
-    except ValueError:
+    except PatternError:
         return False
 
 
@@ -439,7 +443,7 @@ def incr(
     """
     try:
         old_ver_nfo = parse_version_info(old_version, pattern)
-    except ValueError as ex:
+    except PatternError as ex:
         log.error(str(ex))
         return None
 

test/test_rewrite.py

@@ -77,8 +77,8 @@ def test_error_bad_path():
         (project.dir / "setup.py").unlink()
         try:
             list(rewrite._iter_file_paths(cfg.file_patterns))
-            assert False, "expected ValueError"
-        except ValueError as ex:
+            assert False, "expected FileNotFoundError"
+        except FileNotFoundError as ex:
             assert "setup.py" in str(ex)
 
 
@@ -93,6 +93,5 @@ def test_error_bad_pattern():
 
         try:
             list(rewrite.diff("v201809.1234", patterns))
-            assert False, "expected ValueError"
-        except ValueError as ex:
+        except rewrite.NoPatternMatch as ex:
             assert "setup.py" in str(ex)

test/test_version.py

@@ -107,7 +107,7 @@ def test_parse_error_empty():
     try:
         version.parse_version_info("")
         assert False
-    except ValueError as err:
+    except version.PatternError as err:
         pass
 
 
@@ -115,7 +115,7 @@ def test_parse_error_noprefix():
     try:
         version.parse_version_info("201809.0002")
         assert False
-    except ValueError as err:
+    except version.PatternError as err:
         pass
 
 
@@ -123,7 +123,7 @@ def test_parse_error_nopadding():
     try:
         version.parse_version_info("v201809.2b0")
         assert False
-    except ValueError as err:
+    except version.PatternError as err:
         pass