Extract shared AST utilities into astutil package

[jeduden]

Summary

Refactor duplicated AST helper functions from multiple rule packages into a shared astutil package to reduce code duplication and improve maintainability.

Key Changes

• Created internal/rules/astutil/astutil.go with five shared utility functions:

  • HeadingLine(heading, file) - Returns the 1-based source line of a heading node, handling both Setext and ATX heading formats
  • ParagraphLine(para, file) - Returns the 1-based source line of a paragraph node
  • IsTable(para, file) - Detects whether a paragraph is actually a GFM table (goldmark parses tables as paragraphs without the table extension)
  • HeadingText(heading, source) - Extracts plain-text content from a heading by recursively processing its children
  • ExtractText(node, source, buf) - Recursively extracts text content from AST nodes and their descendants

• Created comprehensive test suite in internal/rules/astutil/astutil_test.go covering:

  • Setext and ATX heading line detection
  • Fallback behavior (returns 1 when line info unavailable)
  • Paragraph line detection at various positions
  • Table detection for pipe-delimited content
  • Text extraction with nested emphasis and links

• Updated 7 rule packages to use the shared utilities:

  • blanklinearoundheadings
  • headingincrement
  • noduplicateheadings
  • notrailingpunctuation
  • concisenessscoring
  • paragraphreadability
  • paragraphstructure
  • noemphasisasheading

• Removed duplicate implementations of headingLine, paragraphLine, isTable, headingText, and extractText from individual rule packages

• Cleaned up test files by removing duplicate test coverage that is now centralized in astutil_test.go

Implementation Details

The utilities handle edge cases gracefully:

• HeadingLine checks for line information via Lines() first (Setext headings), then walks child nodes for text segments (ATX headings), with a safe fallback to line 1
• IsTable uses byte-level inspection to detect pipe characters at the start of paragraph lines
• ExtractText recursively processes the AST tree, properly handling both text nodes and container nodes with children

https://claude.ai/code/session_01YbFAKES95Szi7i251Yv1XE

[Copilot]

Pull request overview

Refactors duplicated Goldmark AST helper functions from multiple rule implementations into a shared internal/rules/astutil package, centralizing both logic and tests to reduce per-rule duplication and improve maintainability.

Changes:

• Added internal/rules/astutil with shared helpers for heading/paragraph line detection, table detection, and heading text extraction, plus a new dedicated unit test suite.
• Updated several rules to use astutil helpers and removed now-duplicate private helpers and their associated coverage-only tests.
• Updated plan status tracking in plan/85_coverage-to-95-percent.md and PLAN.md.

Reviewed changes

Copilot reviewed 16 out of 16 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
plan/85_coverage-to-95-percent.md	Marks Phase 2 AST helper extraction tasks as completed/in-progress in the coverage plan.
PLAN.md	Updates the plan index status for plan 85.
internal/rules/astutil/astutil.go	Introduces shared AST utilities (HeadingLine/ParagraphLine/IsTable/HeadingText/ExtractText).
internal/rules/astutil/astutil_test.go	Centralizes tests for the shared AST helpers.
internal/rules/blanklinearoundheadings/rule.go	Switches heading line detection to astutil.HeadingLine.
internal/rules/headingincrement/rule.go	Switches heading line detection to astutil.HeadingLine.
internal/rules/noduplicateheadings/rule.go	Switches heading text/line helpers to astutil.
internal/rules/notrailingpunctuation/rule.go	Switches heading text/line helpers to astutil.
internal/rules/concisenessscoring/rule.go	Switches paragraph line + table detection to astutil.
internal/rules/paragraphreadability/rule.go	Switches paragraph line + table detection to astutil.
internal/rules/paragraphstructure/rule.go	Switches paragraph line + table detection to astutil.
internal/rules/noemphasisasheading/rule.go	Switches paragraph line detection to astutil.
internal/rules/blanklinearoundheadings/rule_coverage_test.go	Removes duplicated headingLine coverage-only tests now covered in astutil_test.go.
internal/rules/headingincrement/rule_coverage_test.go	Removes duplicated headingLine coverage-only tests now covered in astutil_test.go.
internal/rules/noduplicateheadings/rule_coverage_test.go	Removes duplicated headingLine/extractText coverage-only tests now covered in astutil_test.go.
internal/rules/notrailingpunctuation/rule_coverage_test.go	Removes duplicated headingLine/extractText coverage-only tests now covered in astutil_test.go.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 87.21%. Comparing base (24656d9) to head (c11d0a0).
⚠️ Report is 8 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #155      +/-   ##
==========================================
+ Coverage   87.06%   87.21%   +0.14%     
==========================================
  Files          97       98       +1     
  Lines       10346    10287      -59     
==========================================
- Hits         9008     8972      -36     
+ Misses        856      840      -16     
+ Partials      482      475       -7     

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[Copilot]

Pull request overview

Copilot reviewed 15 out of 15 changed files in this pull request and generated 3 comments.

[Copilot]

Pull request overview

Copilot reviewed 15 out of 15 changed files in this pull request and generated no new comments.

[jeduden]

🟢 Merge Queue — picked up

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[jeduden]

🔵 Merge Queue — CI running

Merged into batch branch merge-queue/batch-155-1776802419. View CI run.

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[jeduden]

✅ Merge Queue — merged

This PR landed on main via commit 755cd1a. CI run that validated the merge.

Next: Done — nothing more to do here.