| ## `parse_tag()` raises `ValueError` instead of `InvalidTag` for tags with wrong number of components |
| |
| ### Description |
| |
| Calling `parse_tag()` with a tag string that doesn't have exactly three hyphen-separated components (interpreter, ABI, platform) raises a raw `ValueError` from Python's tuple unpacking instead of the documented `InvalidTag` exception. |
|
|
| For example: |
|
|
| ```python |
| from packaging import tags |
| |
| # Tag with only two components (missing platform) |
| tags.parse_tag("py3-none") |
| |
| # Tag with four components (extra field) |
| tags.parse_tag("py3-none-any-extra") |
| ``` |
|
|
| Running either of these raises: |
|
|
| ``` |
| ValueError: not enough values to unpack (expected 3, got 2) |
| ``` |
|
|
| or |
|
|
| ``` |
| ValueError: too many values to unpack (expected 3) |
| ``` |
|
|
| The error originates from the internal tuple unpacking `interpreters, abis, platforms = component_parts` in `parse_tag()` in `src/packaging/tags.py`. |
|
|
| ### Expected behavior |
|
|
| Both inputs should raise `tags.InvalidTag` (a subclass of `ValueError`) with a message indicating the tag must have exactly three components, consistent with how empty tag components are already handled. Code that catches `InvalidTag` to handle malformed tags should not need to also catch the bare `ValueError`. |
|
|
| ### Actual behavior |
|
|
| A plain `ValueError` is raised directly from the tuple unpacking, bypassing the `InvalidTag` public error contract. Any caller that catches `tags.InvalidTag` to validate tag strings will miss these malformed inputs. |
|
|
| Work in `/workspace`. Submit your fix in the existing Python source files under `src/packaging`. Preserve the other public behavior. The environment is offline; dependencies are preinstalled. Grading runs the repository's test suite in a fresh environment, using your submitted source files. |
|
|
