fix(cli): handle TOML syntax errors gracefully

[sushant-suse]

Changes

Core Logic & CLI

• src/docbuild/cli/cmd_cli.py:
  • Wrapped the handle_config calls for both Application and Environment configurations in try...except blocks to catch tomllib.TOMLDecodeError.
  • Updated handle_validation_error (and its internal logic) to distinguish between TOML syntax errors and Pydantic validation errors.
  • Ensured the specific filename causing the syntax error is passed to the error formatter to provide better context.
  • Initialized configuration dictionaries to prevent Pylance "possibly unbound" warnings.

Utilities

• src/docbuild/utils/errors.py:
  • Added a new format_toml_error function. This uses the rich library to print a clean, red-styled error panel.
  • The panel includes the specific error message from the parser (including line/column) and a helpful hint about TOML boolean casing.

Tests

• tests/utils/test_errors.py: Added a test to verify that the format_toml_error utility correctly captures and formats a syntax error.
• tests/cli/test_cmd_cli.py: Added an end-to-end test that mocks a TOMLDecodeError during the CLI initialization to verify the program exits with code 1 and displays the correct error message without a traceback.

[github-actions]

Coverage Report

For commit 54bc798

Click to expand Coverage Report

  Name                                           Stmts   Miss Branch BrPart  Cover
  --------------------------------------------------------------------------------
+ src/docbuild/models/deliverable.py               180      1     22      0  99.5%
+ src/docbuild/cli/cmd_check/process.py             58      0     22      1  98.8%
+ src/docbuild/models/manifest.py                  111      1     12      1  98.4%
+ src/docbuild/utils/pidlock.py                     79      1     14      1  97.8%
+ src/docbuild/cli/cmd_cli.py                      106      1     12      2  97.5%
+ src/docbuild/cli/cmd_validate/process.py         178      5     52      4  96.1%
+ src/docbuild/cli/callback.py                      35      0     10      2  95.6%
+ src/docbuild/utils/concurrency.py                 69      3     18      1  95.4%
- src/docbuild/cli/cmd_config/__init__.py            9      1      0      0  88.9%
- src/docbuild/config/xml/stitch.py                 47      5     12      0  88.1%
- src/docbuild/cli/cmd_metadata/metaprocess.py     215     26     66     13  82.6%
- src/docbuild/cli/cmd_check/__init__.py            18      5      2      0  65.0%
- src/docbuild/cli/cmd_build/__init__.py            13      5      0      0  61.5%
- src/docbuild/cli/cmd_metadata/__init__.py         27     10      2      0  58.6%
- src/docbuild/cli/cmd_config/environment.py        11      6      2      0  38.5%
  --------------------------------------------------------------------------------
+ TOTAL                                           3011     70    708     25  97.0%
  
  46 files skipped due to complete coverage.

[tomschr]

Thanks @sushant-suse for the work. 👍 It took a bit longer for me.

Overall it looks good. 👍 Apart from minor details, I have some concerns regarding an anti pattern (see below). Not sure if we want to fix it here in this PR as it deviates from the original issue.

[tomschr]

Just a tiny addition, otherwise it's great. 👍 Thank you! I think, it's ready to be squash-merged to main.

[sushant-suse]

Just a tiny addition, otherwise it's great. 👍 Thank you! I think, it's ready to be squash-merged to main.

Also forgot to add fragment file. Added that as well.

[tomschr]

Thanks! 👍