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Why negated ignore patterns need manual review in flat config migration

Understand why negated ignore rules belong in manual review instead of a guessed flat-config translation.

Start here

The safe first move

Treat negated ignore patterns as manual review. The target flat config behavior depends on how the rest of the ignore list is supposed to interact.

Stop before automation when: Rebuilding the intended include/exclude behavior in flat config. Ignore rules mixed with multiple config sources.

Target shape

# manual review required
# negated ignore patterns are outside the deterministic flat-config subset

Repo fit check

Want to know if your repo has this pattern?

Run the matching scanner locally first. The fit-report add-on is not listed for this proof-only product yet, so use the proof page and scanner output before treating it as a purchase candidate.

  • Local scan; no repository upload.
  • Supported findings are separated from manual-review findings.
  • Buy only when the repeated pattern is worth automating.
Run the static-config scan View example report See when to buy 
Example scan summary
supported_findings: 38
manual_review_findings: 6
files_uploaded: 0
confidence: reviewable

Why this page exists

Why negated ignore patterns need manual review in flat config migration

Simple ignore rules can move mechanically. Negated patterns need a closer read.

Direct answer

What changes

Treat negated ignore patterns as manual review. The target flat config behavior depends on how the rest of the ignore list is supposed to interact.

Example

Before and after

Before

dist/
!dist/keep.js

After

# manual review required
# negated ignore patterns are outside the deterministic flat-config subset

Decision path

If this repeats across the repo, open the evaluation pages next.

This product exists for the static-config subset. It does not pretend to evaluate JS config logic.

  • Teams migrating static .eslintrc JSON or YAML configs.
  • Repos that still store eslintConfig inside package.json.
  • The fit-report add-on is not listed for this proof-only product yet; use the proof page and scanner output before treating this as purchasable.

Before checkout

Product fit, proof, and price should all be one click away.

Current listed price is not published on the pricing page yet.

Typical symptoms

  • The repo already uses exceptions inside .eslintignore or ignorePatterns.
  • A guessed migration can silently change which files are linted.
  • Teams want a clean stop signal instead of a risky translation.

What the product covers

  • Explicit unsupported ignore-pattern findings.
  • Cross-links to the supported .eslintignore migration page.
  • Repo-fit guidance before buying the flat-config pack.

Manual-review boundary

  • Rebuilding the intended include/exclude behavior in flat config.
  • Ignore rules mixed with multiple config sources.
  • Repos that already started a custom flat-config migration.

Keep the migration narrow

Use the exact-problem guides as a triage layer, then decide whether the repo is inside the supported subset.

FAQ

Fast answers before you decide

What is the safest fix for negated ignore patterns flat config?

Treat negated ignore patterns as manual review. The target flat config behavior depends on how the rest of the ignore list is supposed to interact.

Can negated ignore patterns flat config be automated?

Automate only the supported subset: Explicit unsupported ignore-pattern findings. Cross-links to the supported .eslintignore migration page. Repo-fit guidance before buying the flat-config pack. Keep these cases in manual review: Rebuilding the intended include/exclude behavior in flat config. Ignore rules mixed with multiple config sources. Repos that already started a custom flat-config migration.

When should I buy ESLint Flat Config Migration Cleanup Pack?

Use ESLint Flat Config Migration Cleanup Pack only when this pattern repeats across enough files that manual cleanup is still costly. Run the public scan or read the proof first. The fit-report add-on is not listed for this proof-only product yet; if unsupported findings dominate, keep the work manual.