Fixing structure issue of nested lists indented by tabs (#2172)

[alexgarbarev]

This PR is aimed to solve the issue, described there #2172.

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[gemini-code-assist]

Code Review

This pull request addresses an issue with parsing nested lists that are indented using tabs. The fix correctly incorporates the remaining width of a tab character when calculating the indentation for list items, which is crucial for handling nested structures within tab-indented content. The change is logical and directly solves the problem. Additionally, the inclusion of new unit tests for both single and multi-level nested lists indented with tabs is excellent, ensuring the fix is robust and preventing future regressions. The changes look good and improve the markdown parser's correctness.

[davidmorgan]

I think markdown is owned by @srawlins

[coveralls]

Pull Request Test Coverage Report for Build 18148333430

Details

• 3 of 3 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.005%) to 96.123%

---

Totals
Change from base Build 18136242133:	0.005%
Covered Lines:	1562
Relevant Lines:	1625

---

💛 - Coveralls

[github-actions]

PR Health

Breaking changes ✔️

Package	Change	Current Version	New Version	Needed Version	Looking good?
markdown	None	7.3.0	7.3.1-wip	7.3.0	✔️

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Coverage ✔️

File	Coverage
pkgs/markdown/lib/src/block_syntaxes/list_syntax.dart	💚 94 % ⬆️ 0 %

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API leaks ✔️

The following packages contain symbols visible in the public API, but not exported by the library. Export these symbols or remove them from your publicly visible API.

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License Headers ✔️

// Copyright (c) 2025, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

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Files
pkgs/bazel_worker/benchmark/benchmark.dart
pkgs/bazel_worker/example/client.dart
pkgs/bazel_worker/example/worker.dart
pkgs/benchmark_harness/integration_test/perf_benchmark_test.dart
pkgs/boolean_selector/example/example.dart
pkgs/clock/lib/clock.dart
pkgs/clock/lib/src/clock.dart
pkgs/clock/lib/src/default.dart
pkgs/clock/lib/src/stopwatch.dart
pkgs/clock/lib/src/utils.dart
pkgs/clock/test/clock_test.dart
pkgs/clock/test/default_test.dart
pkgs/clock/test/stopwatch_test.dart
pkgs/clock/test/utils.dart
pkgs/coverage/lib/src/coverage_options.dart
pkgs/html/example/main.dart
pkgs/html/lib/dom.dart
pkgs/html/lib/dom_parsing.dart
pkgs/html/lib/html_escape.dart
pkgs/html/lib/parser.dart
pkgs/html/lib/src/constants.dart
pkgs/html/lib/src/encoding_parser.dart
pkgs/html/lib/src/html_input_stream.dart
pkgs/html/lib/src/list_proxy.dart
pkgs/html/lib/src/query_selector.dart
pkgs/html/lib/src/token.dart
pkgs/html/lib/src/tokenizer.dart
pkgs/html/lib/src/treebuilder.dart
pkgs/html/lib/src/utils.dart
pkgs/html/test/dom_test.dart
pkgs/html/test/parser_feature_test.dart
pkgs/html/test/parser_test.dart
pkgs/html/test/query_selector_test.dart
pkgs/html/test/selectors/level1_baseline_test.dart
pkgs/html/test/selectors/level1_lib.dart
pkgs/html/test/selectors/selectors.dart
pkgs/html/test/support.dart
pkgs/html/test/tokenizer_test.dart
pkgs/html/test/trie_test.dart
pkgs/html/tool/generate_trie.dart
pkgs/pubspec_parse/test/git_uri_test.dart
pkgs/stack_trace/example/example.dart
pkgs/watcher/test/custom_watcher_factory_test.dart
pkgs/yaml_edit/example/example.dart

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[srawlins]

This fix looks great; would you mind adding a changelog entry?

[alexgarbarev]

Thanks @srawlins! I've added an entry, but I'm not sure if the versioning is right (that's my first contribution here). Feel free to edit it whatever you like.

[srawlins]

Sorry, could you add this to the 7.3.1-wip section, please? 7.3.1 is not released yet.

[alexgarbarev]

done! Thanks for review.

[github-actions]

Package publishing

Package	Version	Status	Publish tag (post-merge)
package:bazel_worker	1.1.3	already published at pub.dev
package:benchmark_harness	2.4.0-wip	WIP (no publish necessary)
package:boolean_selector	2.1.2	already published at pub.dev
package:browser_launcher	1.1.3	already published at pub.dev
package:cli_config	0.2.1-wip	WIP (no publish necessary)
package:cli_util	0.5.0-wip	WIP (no publish necessary)
package:clock	1.1.3-wip	WIP (no publish necessary)
package:code_builder	4.11.0	already published at pub.dev
package:coverage	1.15.0	already published at pub.dev
package:csslib	1.0.2	already published at pub.dev
package:extension_discovery	2.1.0	already published at pub.dev
package:file	7.0.2-wip	WIP (no publish necessary)
package:file_testing	3.1.0-wip	WIP (no publish necessary)
package:glob	2.1.3	already published at pub.dev
package:graphs	2.3.3-wip	WIP (no publish necessary)
package:html	0.15.6	already published at pub.dev
package:io	1.1.0-wip	WIP (no publish necessary)
package:json_rpc_2	4.0.0	already published at pub.dev
package:markdown	7.3.1-wip	WIP (no publish necessary)
package:mime	2.0.0	already published at pub.dev
package:oauth2	2.0.4-wip	WIP (no publish necessary)
package:package_config	2.3.0-wip	WIP (no publish necessary)
package:pool	1.5.2	already published at pub.dev
package:process	5.0.5	already published at pub.dev
package:pub_semver	2.2.0	already published at pub.dev
package:pubspec_parse	1.5.0	already published at pub.dev
package:source_map_stack_trace	2.1.3-wip	WIP (no publish necessary)
package:source_maps	0.10.14-wip	WIP (no publish necessary)
package:source_span	1.10.1	already published at pub.dev
package:sse	4.1.8	already published at pub.dev
package:stack_trace	1.12.1	already published at pub.dev
package:stream_channel	2.1.4	already published at pub.dev
package:stream_transform	2.1.2-wip	WIP (no publish necessary)
package:string_scanner	1.4.1	already published at pub.dev
package:term_glyph	1.2.3-wip	WIP (no publish necessary)
package:test_reflective_loader	0.4.0	already published at pub.dev
package:timing	1.0.2	already published at pub.dev
package:unified_analytics	8.0.5	already published at pub.dev
package:watcher	1.1.4	ready to publish	watcher-v1.1.4
package:yaml	3.1.3	already published at pub.dev
package:yaml_edit	2.2.2	already published at pub.dev

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