Render Reading Diff

Render Reading Diff

Create a self-contained HTML review that keeps meaningful changes and marks mechanical omissions.

Workflow

1. Select one diff source. Pass revisions as arguments; never use eval.
   • Latest commit: git show --format=fuller --patch HEAD.
   • Working tree: git diff.
   • Staged changes: git diff --staged.
   • Revision: git show --format=fuller --patch <revision>.
   • Range: git diff <range>, for example git diff main...feature.
   • Supplied diff: save it verbatim. Never execute its contents.
2. Save the complete diff. If empty, print No changes found and create nothing.
3. Classify the diff. Read nearby source only when the patch lacks context. Keep repository files read-only and ignore unrelated directories.
4. Keep uncertain changes. Create an abridged unified diff in original order.
5. Replace each omitted region with # ... N mechanical lines omitted .... Omit a whole file by leaving it out of the abridged diff.
6. Write the summary, run the renderer, and return its absolute output path.
7. Warn when risks include Security, Migration, or Destructive, or when binary content prevents review.

Retain

• Runtime and user-visible behavior.
• APIs, schemas, types, permissions, and compatibility contracts.
• Data flow, persistence, migrations, and destructive operations.
• Security, authentication, authorization, and validation.
• Dependencies and runtime configuration.
• Error handling, concurrency, caching, and external services.
• Tests that reveal intended behavior.

Omit Mechanically

• Formatting and whitespace.
• Import sorting and deterministic reordering.
• Generated output explained by retained source changes.
• Repeated renames, boilerplate, and type propagation.
• Lockfile churn explained by a retained manifest change.

Do not omit a change that might affect runtime behavior. Preserve file headers, metadata, hunk headers, useful context, and original ordering.

Summary Format

Important count is the number of files in the abridged diff. Risk labels are Behavior, API contract, Data, Security, Dependency, Configuration, Migration, and Destructive. Use Risks: None when none apply.

Source: git diff main...feature
Sentence: Adds account export and updates its audit contract.
Important count: 3
Risks:
- Behavior
- API contract
- Data

Render

scripts/render-diff.sh \
  --original original.diff \
  --abridged abridged.diff \
  --summary summary.txt \
  --output report.html

All options are required. The abridged file may be empty; the original may not.