Improve CRLF handling in the decoder

[smortezah]

This pull request improves cross-platform compatibility in the toon_format scanner and decoder by normalizing different line endings (Windows CRLF and old Mac CR) to LF, ensuring consistent parsing behavior regardless of the source file's origin. It also adds comprehensive tests to verify correct handling of various line ending scenarios.

Line ending normalization:

• Updated src/toon_format/_scanner.py to normalize Windows CRLF (\r\n) and old Mac CR (\r) line endings to LF (\n) before parsing, preventing stray carriage return characters from appearing in parsed content.

Test coverage improvements:

• Added TestCRLFDecoding in tests/test_decoder.py to verify that the decoder correctly handles CRLF, CR, mixed line endings, and quoted strings containing escaped \r and \n sequences, including strict mode decoding.
• Added TestCRLFHandling in tests/test_scanner.py to ensure the scanner normalizes all types of line endings, preserves indentation, and works correctly in strict mode.

[Justar96]

Hi @smortezah,
Thanks for the pull request. Could you please resend it with the PR form? [](https://github.com/toon-format/toon-python/blob/main/.github/PULL_REQUEST_TEMPLATE.md) same with #21

[Copilot]

Pull Request Overview

This PR enhances cross-platform compatibility by normalizing different line ending formats (CRLF, CR, LF) to a consistent LF format before parsing, preventing issues with files created on different operating systems.

Key Changes:

• Added line ending normalization logic in the scanner to handle Windows (CRLF) and old Mac (CR) formats
• Implemented comprehensive test coverage for CRLF/CR handling in both scanner and decoder
• Ensured escaped sequences in quoted strings are preserved during normalization

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
src/toon_format/_scanner.py	Added line ending normalization logic to convert CRLF and CR to LF
tests/test_scanner.py	Added TestCRLFHandling class with tests for various line ending scenarios
tests/test_decoder.py	Added TestCRLFDecoding class to verify decoder handles different line endings correctly

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[bpradana]

approved despite CI failed on lint
🚀🚀🚀

[johannschopplich]

Hey @smortezah – I've been going through the open PRs and yours stand out. The CRLF normalization, numeric validation fix, and pathlib support are all well-scoped, properly tested, and ready to go. Exactly the kind of work this project needs more of.

I just opened a discussion about bringing in new contributors with merge access: #52

If you're interested in being more involved, I'd love to have you.

[smortezah]

@johannschopplich I'll be glad to help.

[smortezah]

There is an issue with the lint GitHub action, that makes one of the checks here fail.

I've made the PR #53 to fix it.

[johannschopplich]

@alesanfra this one's been sitting for a while and looks solid to me – happy if you want to take a quick look and merge if it checks out! 🙌

[alesanfra]

LGTM but some checks are failing, @smortezah can you please look into it? Thanks