fix(static): handle weighted accept-encoding values

[MFA-G]

Linked issue

Resolves #4457

Type of change

• Bug fix (a non-breaking change that fixes an issue)
• Documentation
• New feature
• Chore
• Breaking change

Description

Strip optional parameters from each Accept-Encoding token before looking it up in the compressed-asset encoding map. This lets standard weighted values such as gzip; q=1.0 and br; q=0.9 match their precompressed assets instead of silently falling back to the uncompressed file, matching the RFC 9110 grammar for Accept-Encoding.

A focused unit regression test verifies that a weighted header selects the gzip asset and sets Content-Encoding: gzip.

Checklist

• I have linked an issue.
• Documentation not needed (internal parser bug fix, no public API change).
• I have added tests to cover my changes.
• I have run the tests and lint locally and they pass.

Validation

• pnpm vitest run test/unit/static-middleware.test.ts (3 passed)
• pnpm lint
• pnpm stub
• pnpm typecheck

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[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: b1ca3807-3191-41f9-9105-ac004c1f40f7

📥 Commits

Reviewing files that changed from the base of the PR and between 471cc0d and 0015bab.

📒 Files selected for processing (2)

• src/runtime/internal/static.ts
• test/unit/static-middleware.test.ts

🚧 Files skipped from review as they are similar to previous changes (1)

• src/runtime/internal/static.ts

---

📝 Walkthrough

Walkthrough

The static middleware now normalizes Accept-Encoding tokens, excludes encodings with q=0, and supports compressed asset selection when quality parameters are present. Tests cover gzip selection and fallback to the uncompressed asset.

Changes

Accept-Encoding support

Layer / File(s)	Summary
Weighted encoding lookup and validation src/runtime/internal/static.ts, test/unit/static-middleware.test.ts	Encoding tokens are normalized before EncodingMap lookup, q=0 encodings are excluded, and tests cover gzip selection and uncompressed fallback.

Estimated code review effort: 2 (Simple) | ~10 minutes

Possibly related PRs

• nitrojs/nitro#4075: Updates related Accept-Encoding handling in the static middleware during asset resolution.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title follows conventional commit format and clearly describes the weighted Accept-Encoding fix.
Description check	✅ Passed	The description directly matches the patch and explains the q-value parsing fix and added test coverage.
Linked Issues check	✅ Passed	The code strips optional q-parameters before EncodingMap lookup, which satisfies issue #4457's main requirement.
Out of Scope Changes check	✅ Passed	The changes stay focused on Accept-Encoding parsing and regression tests, with no evident unrelated additions.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@src/runtime/internal/static.ts`:
- Line 24: Update the Accept-Encoding parsing in the encoding-selection map to
read each entry’s q parameter, exclude entries with q=0 before sorting or
selecting encodings, and preserve existing behavior for positive or omitted
quality values. Ensure requests such as gzip; q=0 do not select compressed
assets.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 9fe0fe8c-eccc-4a8a-820e-cc488e89fde1

📥 Commits

Reviewing files that changed from the base of the PR and between 77b77ff and 645e138.

📒 Files selected for processing (2)

• src/runtime/internal/static.ts
• test/unit/static-middleware.test.ts

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@src/runtime/internal/static.ts`:
- Line 31: Normalize the trimmed Accept-Encoding token to lowercase before
indexing EncodingMap, so case variants such as GZIP, Br, and ZSTD resolve to the
existing encodings while preserving the current lookup flow.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 469981da-e6f6-408d-aa42-721b8405d1f0

📥 Commits

Reviewing files that changed from the base of the PR and between 645e138 and 471cc0d.

📒 Files selected for processing (2)

• src/runtime/internal/static.ts
• test/unit/static-middleware.test.ts

🚧 Files skipped from review as they are similar to previous changes (1)

• test/unit/static-middleware.test.ts