Improve config resolution and add error handling for paths

Refactor `process_value` to handle `None` values and raise a `BumpVersionError` for non-existent files. Update related tests to ensure correct behavior for missing, existing, and URL-based config paths. These changes enhance robustness and user feedback in handling configuration inputs.

Author: coordt

bumpversion/click_config.py

@@ -9,7 +9,7 @@
 from click import Context, Option
 from click.decorators import FC, _param_memo  # noqa: PLC2701
 
-from bumpversion.exceptions import BadInputError
+from bumpversion.exceptions import BadInputError, BumpVersionError
 from bumpversion.ui import get_indented_logger
 
 logger = get_indented_logger(__name__)
@@ -65,10 +65,10 @@ def __init__(
             **attrs,
         )
 
-    def process_value(self, ctx: Context, value: Any) -> Path:
+    def process_value(self, ctx: Context, value: Any) -> Optional[Path]:
         """Process the value of the option."""
         value = super().process_value(ctx, value)
-        return resolve_conf_location(value)
+        return resolve_conf_location(value) if value else None
 
 
 def config_option(*param_decls: str, cls: Optional[type[ConfigOption]] = None, **attrs: Any) -> Callable[[FC], FC]:
@@ -108,6 +108,9 @@ def resolve_conf_location(url_or_path: str) -> Path:
     Args:
         url_or_path: The URL or path to resolve.
 
+    Raises:
+        BumpVersionError: if the file does not exist.
+
     Returns:
         The contents of the location.
     """
@@ -116,7 +119,10 @@ def resolve_conf_location(url_or_path: str) -> Path:
     if parsed_url.scheme in ("http", "https"):
         return download_url(url_or_path)
 
-    return Path(url_or_path)
+    path = Path(url_or_path)
+    if not path.exists():
+        raise BumpVersionError(f"'{path}' does not exist.")
+    return path
 
 
 def download_url(url: str) -> Path:

tests/test_click_config.py

@@ -1,32 +1,63 @@
 """Tests for the bumpversion.click_config module."""
 
 from pathlib import Path
+from typing import Optional
 
 import click
 import httpx
 import pytest
 
-from bumpversion.click_config import config_option, resolve_conf_location, download_url
+from bumpversion.click_config import config_option, download_url, resolve_conf_location
 from bumpversion.exceptions import BadInputError
 
 
 @click.command()
 @config_option()
-def hello(config: Path):
+def hello(config: Optional[Path]):
     """Say hello."""
     click.echo(f"Hello {config}!")
-    click.echo(f"path exists: {config.exists()}")
+    if config:
+        click.echo(f"path exists: {config.exists()}")
+    else:
+        click.echo("Nothing was passed.")
 
 
 class TestConfigOption:
     """Tests to for config_option."""
 
-    def test_config_option(self, runner):
-        """Passing an invalid option should raise an error."""
+    def test_passing_missing_file_raises_error(self, runner):
+        """Explicitly passing a path that does not exist should raise an error."""
         result = runner.invoke(hello, ["--config", "idont/exist.txt"])
 
+        assert result.exit_code != 0
+
+    def test_passing_nothing_returns_none(self, runner):
+        """If nothing is passed, the value is `None`."""
+        result = runner.invoke(hello, [])
+
+        assert result.exit_code == 0
+        assert "Hello None!" in result.output
+
+    def test_passing_existing_file_returns_path(self, runner, fixtures_path: Path):
+        """Passing an existing file path should return a Path object."""
+        config_path = fixtures_path / "basic_cfg.toml"
+        result = runner.invoke(hello, ["--config", str(config_path)])
+
+        assert result.exit_code == 0
+        assert f"Hello {config_path}!" in result.output
+
+    def test_passing_url_returns_path(self, runner, fixtures_path: Path, httpserver):
+        """Passing an existing file path should return a Path object."""
+        # Assemble
+        config = fixtures_path.joinpath("basic_cfg.toml").read_text()
+        httpserver.serve_content(config)
+
+        # Act
+        result = runner.invoke(hello, ["--config", f"{httpserver.url}/basic_cfg.toml"])
+
+        # Assert
         assert result.exit_code == 0
-        assert "path exists: False" in result.output
+        assert "path exists: True" in result.output
 
 
 class TestResolveConfLocation:
@@ -39,45 +70,37 @@ def test_resolves_file_path(self, fixtures_path: Path):
         assert isinstance(result, Path)
         assert result == dummy_path
 
-    def test_resolves_valid_url(self, mocker):
+    def test_resolves_valid_url(self, fixtures_path: Path, httpserver):
         """Should download the file if given a valid URL."""
         # Arrange
-        mocked_download = mocker.patch(
-            "bumpversion.click_config.download_url", return_value=Path("/tmp/downloaded_config.txt")
-        )
-        url = "http://example.com/config.txt"
+        config = fixtures_path.joinpath("basic_cfg.toml").read_text()
+        httpserver.serve_content(config)
+        url = f"{httpserver.url}/basic_cfg.toml"
 
         # Act
         result = resolve_conf_location(url)
 
         # Assert
-        mocked_download.assert_called_once_with(url)
         assert isinstance(result, Path)
-        assert str(result) == "/tmp/downloaded_config.txt"
+        assert result.read_text() == config
 
 
 class TestDownloadUrl:
     """Tests for download_url."""
 
-    def test_download_url_success(self, mocker, tmp_path: Path):
+    def test_download_url_success(self, fixtures_path: Path, httpserver):
         """Should return a Path for a valid request."""
         # Arrange
-        mock_response = mocker.Mock(spec=httpx.Response)
-        mock_response.status_code = 200
-        mock_response.text = "content"
-        mocker.patch("httpx.get", return_value=mock_response)
-        tmp_file = tmp_path / "tempfile.txt"
-        mock_tempfile = mocker.patch("bumpversion.click_config.NamedTemporaryFile", autospec=True)
-        temp_file_instance = mock_tempfile.return_value.__enter__.return_value
-        temp_file_instance.name = str(tmp_file)
+        config = fixtures_path.joinpath("basic_cfg.toml").read_text()
+        httpserver.serve_content(config)
+        url = f"{httpserver.url}/basic_cfg.toml"
 
         # Act
-        result = download_url("http://example.com/config.txt")
+        result = download_url(url)
 
         # Assert
         assert isinstance(result, Path)
-        assert result == tmp_file
-        mock_tempfile.assert_called_once()
+        assert result.read_text() == config
 
     def test_download_url_request_error(self, mocker):
         """Should raise BadInputError for a RequestError."""