dirien/go-nolint-audit

<!-- Copyright 2025-2026 Richard Shade. Licensed under Apache-2.0. --> <!-- SPDX-License-Identifier: Apache-2.0 -->

Go Nolint Audit

Audit //nolint: directives in Go codebases. Finds suppressions that are stale (code changed, lint rule no longer triggers) or lazily justified (the underlying code could be fixed instead of suppressed). Challenges each justification through adversarial debate rather than accepting comments at face value.

Prerequisite check

go version 2>/dev/null && golangci-lint --version 2>/dev/null

If go is not installed, stop and report. If golangci-lint is missing:

• Install from https://golangci-lint.run/welcome/install/

Do not proceed without both tools available.

Discover nolint directives

grep -rn '//nolint' --include='*.go' . | grep -v vendor/

Match all variants: //nolint (bare), //nolint:rule, //nolint:rule1,rule2. For each directive, capture:

• File and line number
• Suppressed rule(s), or "bare" if no rule specified
• Justification comment (text after //nolint:rule // if present)
• Surrounding code context (~5 lines)

Bare //nolint (no rule) suppresses everything — flag for Phase 2 automatically. If zero directives found, report a clean codebase and stop.

Phase 1: Mechanical verification

For each directive with a named rule, test whether the suppression is still needed. Co-enable nolintlint alongside the target rule:

# v2 syntax (preferred):
golangci-lint run --enable-only=<rule>,nolintlint \
  --allow-parallel-runners <file>

# v1 syntax (if v2 unavailable):
golangci-lint run --disable-all --enable=<rule>,nolintlint \
  --allow-parallel-runners <file>

If nolintlint reports the directive as unused, it is stale. This avoids modifying source files. For multi-rule directives (//nolint:rule1,rule2), test each rule separately. Run up to 3 parallel shell commands. Always use --allow-parallel-runners.

If golangci-lint fails for reasons other than the target rule (build errors, missing deps), skip the directive and report as "unable to verify."

Categorize each directive:

• Stale — rule no longer triggers. Safe to remove.
• Active — rule still triggers. Moves to Phase 2.

Report stale directives immediately. If all are stale, skip Phase 2. Bare //nolint directives skip Phase 1 — they cannot be verified against a specific rule.

Phase 2: Adversarial debate

Score all discovered directives (not just the Phase 1 sample) on two dimensions (1-5). For large codebases (50+ directives), sample 5-10 across different rules for Phase 1, but score the full list here to find the worst offenders:

• Fixability — how easy to fix the code instead of suppressing?
  • 5 = trivial (extract function, rename, add constant)
  • 3 = moderate (restructure logic, split function)
  • 1 = architectural change required
• Justification quality — how convincing is the comment?
  • 5 = no comment, or vague ("complexity is inherent", "needed")
  • 3 = explains situation but not why fixing is worse
  • 1 = specific, compelling reason

Score = Fixability x Justification quality. Consult references/go-nolint-patterns.md for scoring guidance.

Debate the top 3 by score:

• Red (remove): argues the nolint should be removed and the code fixed. Must propose a concrete diff. Challenges the justification.
• Blue (keep): argues the nolint is correct. Must add reasoning beyond the existing comment. Points out risks of the proposed fix.
• White (judge): evaluates on evidence. Decides: remove, keep, or rewrite justification.

Debate rules

• Red and Blue must cite specific code, not generalities
• Red must provide a concrete diff, not just "this could be simpler"
• Blue cannot simply repeat the existing justification
• White's decision is final

Output format

Phase 1

Stale (safe to remove):
  file.go:42  //nolint:errcheck — rule no longer triggers
  file.go:87  //nolint:mnd — rule no longer triggers

Unable to verify:
  file.go:99  //nolint:gosec — golangci-lint build error

Phase 2

For each debated directive:

#N: file.go:line — //nolint:rule

Current code (with nolint): [5-10 lines of surrounding code]

Justification: "original comment" Lint warning when removed: [exact golangci-lint output]

Red (remove): [argument + concrete diff] Blue (keep): [argument with specific reasoning] White (verdict): REMOVE | KEEP | REWRITE JUSTIFICATION [reasoning]

[If REMOVE: repeat diff for easy application] [If REWRITE: full replacement line with improved justification]

Summary

| # | File:Line | Rule | Verdict | Effort | | - | --------- | ---- | ------- | ------ | | 1 | location | rule | verdict | effort | | 2 | location | rule | verdict | effort | | 3 | location | rule | verdict | effort |

Stale: N (remove immediately) | Unable to verify: N