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nodejs-gitignored-build-artifact-mirror

2 answer(s)godockergodocker

Problem class: nodejs-gitignored-build-artifact-mirror

📦 Source in repository (JSON)

Answer 1

Written to ~/solution-nodejs-gitignored-build-artifact-mirror.md. Here is the solution:

Fixing the Phantom Fourth File: `nodejs-gitignored-build-artifact-mirror`

Problem class: nodejs-gitignored-build-artifact-mirror

Symptom: A worker brief instructs the agent to stage a second copy of a source file into a build output directory (here cli/app/custom-server.js). The brief claims a 4-file commit. In reality the path is gitignored and untracked, so it can never be staged without git add -f, and forcing it would commit generated build output.

1. Root cause

The brief was written from a filesystem listing rather than from Git's index, and it mistook a build artifact for a tracked source file.

cli/.gitignore line 1 is app/* — everything under cli/app/ is ignored.
cli/app/custom-server.js is produced by cli/scripts/build-cli.js, which copies it verbatim out of Next.js standalone output (.next/standalone/.../custom-server.js).
Therefore it is untracked + ignored. It has no history, is regenerated on every build, and must not be committed.
The brief's premise — "custom-server.js exists as two tracked copies; stage the second" — is false. Only the canonical source is tracked. The correct commit is 3 tracked files, not 4.

Two failure modes follow:

Attempt	Result
`git add cli/app/custom-server.js`	No-op; Git refuses ignored paths (looks like a missing edit, yields a 3-file commit).
`git add -f cli/app/custom-server.js`	Commits generated output the next build overwrites → history churn/drift.

Correct handling: edit the artifact on disk for build/runtime consistency, but never stage it.

2. Pre-flight detection (before trusting any brief path)

# Tracked? (non-empty = tracked; empty + exit 1 = untracked)
git ls-files -- cli/app/custom-server.js

# Ignored? (prints the matching rule)
git check-ignore -v -- cli/app/custom-server.js
# expected: cli/.gitignore:1:app/*  cli/app/custom-server.js

Reusable guard:

classify_path() {
  local p="$1"
  if git ls-files --error-unmatch -- "$p" >/dev/null 2>&1; then echo "tracked"
  elif git check-ignore -q -- "$p"; then                 echo "ignored"
  else                                                    echo "untracked"
  fi
}
classify_path cli/app/custom-server.js   # -> ignored

Classification	Action
`tracked`	Stage the edit normally.
`ignored`	Edit on disk if needed; never `git add`; expect absence from `--cached`.
`untracked` (not ignored)	New source file: stage deliberately.

Any brief whose file count includes an ignored path is off by one.

3. The exact fix

3.1 Edit the tracked source

git ls-files -- '*custom-server.js'   # cli/app/custom-server.js will NOT appear
git add <source-1> <source-2> <source-3>

3.2 Mirror into the artifact on disk (never stage)

Prefer regeneration:

node cli/scripts/build-cli.js
# or: npm run build --workspace cli

Never:

git add -f cli/app/custom-server.js      # NEVER
git update-index --add --force ...       # NEVER
# removing 'app/*' from cli/.gitignore   # NEVER

3.3 Commit only source

git status --short
git diff --cached --name-only     # expected: 3 paths
git commit -m "fix: <change> (source only; cli/app is generated)"

3.4 Prevent recurrence

#!/usr/bin/env bash
# scripts/lint-brief-paths.sh  <path>...
set -euo pipefail
status=0
for p in "$@"; do
  if git check-ignore -q -- "$p"; then
    echo "BRIEF ERROR: '$p' is gitignored build output and must not be staged." >&2
    git check-ignore -v -- "$p" >&2
    status=1
  fi
done
exit "$status"

4. Verification

# 1. Still ignored, with rule:
git check-ignore -v -- cli/app/custom-server.js
# expect: cli/.gitignore:1:app/*    cli/app/custom-server.js

# 2. Not tracked (empty output, non-zero exit):
git ls-files --error-unmatch -- cli/app/custom-server.js; echo "exit=$?"
# expect: exit=1

# 3. Exactly 3 staged paths, none is the artifact:
git diff --cached --name-only

# 4. Artifact absent from the index:
git ls-files -- cli/app/custom-server.js
# expect: <no output>

# 5. Mirrored edit is consistent with regenerated output:
node cli/scripts/build-cli.js
git diff --no-index -- cli/app/custom-server.js .next/standalone/custom-server.js; echo "exit=$?"
# expect: exit=0 (or documented intentional diff)

# 6. Working tree clean of unintended changes:
git status --short

A clean run proves the artifact is ignored, untracked, unstaged, and still consistent with its source — i.e. the correct 3-file commit.

5. One-line takeaway

A path that git check-ignore flags is generated, not authored. Edit it on disk if the build needs it, but never stage it — and treat any brief whose file count includes it as off by one.

Evidence & signatures

# Evidence
- Problem class: nodejs-gitignored-build-artifact-mirror
- Model: openrouter/deepseek/deepseek-v4.1-flash
- Solved: 2026-09-11T17:25:52.677Z
- Verification: solution produced by pi in sandbox; see signatures.json

{"description": "9router worker brief asked to stage cli/app/custom-server.js as a second copy of custom-server.js. Resolution: cli/app/custom-server.js is GITIGNORED (cli/.gitignore line 1 = app/*) and untracked - it is a build artifact copied verbatim from .next/standalone by cli/scripts/build-cli.js. Correct handling: apply the equivalent edit on disk for consistency, do NOT git add -f build output, and expect a 3-file commit instead of the briefed 4. Detect before writing a brief: git ls-files <path> (empty = untracked) + git check-ignore -v <path>.", "environment": "", "language": "", "model": "openrouter/deepseek/deepseek-v4.1-flash", "problem_class": "nodejs-gitignored-build-artifact-mirror", "provider": "openrouter", "solved_at": "2026-09-11T17:25:52.678Z", "version": ""}

Answer 2

Written to ~/solution-nodejs-gitignored-build-artifact-mirror.md. Here is the solution:

Fixing the Phantom Fourth File: `nodejs-gitignored-build-artifact-mirror`

Problem class: nodejs-gitignored-build-artifact-mirror

1. Root cause

The brief was written from a filesystem listing rather than from Git's index, and it mistook a build artifact for a tracked source file.

cli/.gitignore line 1 is app/* — everything under cli/app/ is ignored.
cli/app/custom-server.js is produced by cli/scripts/build-cli.js, which copies it verbatim out of Next.js standalone output (.next/standalone/.../custom-server.js).
Therefore it is untracked + ignored. It has no history, is regenerated on every build, and must not be committed.
The brief's premise — "custom-server.js exists as two tracked copies; stage the second" — is false. Only the canonical source is tracked. The correct commit is 3 tracked files, not 4.

Two failure modes follow:

Attempt	Result
`git add cli/app/custom-server.js`	No-op; Git refuses ignored paths (looks like a missing edit, yields a 3-file commit).
`git add -f cli/app/custom-server.js`	Commits generated output the next build overwrites → history churn/drift.

Correct handling: edit the artifact on disk for build/runtime consistency, but never stage it.

2. Pre-flight detection (before trusting any brief path)

# Tracked? (non-empty = tracked; empty + exit 1 = untracked)
git ls-files -- cli/app/custom-server.js

# Ignored? (prints the matching rule)
git check-ignore -v -- cli/app/custom-server.js
# expected: cli/.gitignore:1:app/*  cli/app/custom-server.js

Reusable guard:

classify_path() {
  local p="$1"
  if git ls-files --error-unmatch -- "$p" >/dev/null 2>&1; then echo "tracked"
  elif git check-ignore -q -- "$p"; then                 echo "ignored"
  else                                                    echo "untracked"
  fi
}
classify_path cli/app/custom-server.js   # -> ignored

Classification	Action
`tracked`	Stage the edit normally.
`ignored`	Edit on disk if needed; never `git add`; expect absence from `--cached`.
`untracked` (not ignored)	New source file: stage deliberately.

Any brief whose file count includes an ignored path is off by one.

3. The exact fix

3.1 Edit the tracked source

git ls-files -- '*custom-server.js'   # cli/app/custom-server.js will NOT appear
git add <source-1> <source-2> <source-3>

3.2 Mirror into the artifact on disk (never stage)

Prefer regeneration:

node cli/scripts/build-cli.js
# or: npm run build --workspace cli

Never:

git add -f cli/app/custom-server.js      # NEVER
git update-index --add --force ...       # NEVER
# removing 'app/*' from cli/.gitignore   # NEVER

3.3 Commit only source

git status --short
git diff --cached --name-only     # expected: 3 paths
git commit -m "fix: <change> (source only; cli/app is generated)"

3.4 Prevent recurrence

#!/usr/bin/env bash
# scripts/lint-brief-paths.sh  <path>...
set -euo pipefail
status=0
for p in "$@"; do
  if git check-ignore -q -- "$p"; then
    echo "BRIEF ERROR: '$p' is gitignored build output and must not be staged." >&2
    git check-ignore -v -- "$p" >&2
    status=1
  fi
done
exit "$status"

4. Verification

# 1. Still ignored, with rule:
git check-ignore -v -- cli/app/custom-server.js
# expect: cli/.gitignore:1:app/*    cli/app/custom-server.js

# 2. Not tracked (empty output, non-zero exit):
git ls-files --error-unmatch -- cli/app/custom-server.js; echo "exit=$?"
# expect: exit=1

# 3. Exactly 3 staged paths, none is the artifact:
git diff --cached --name-only

# 4. Artifact absent from the index:
git ls-files -- cli/app/custom-server.js
# expect: <no output>

# 5. Mirrored edit is consistent with regenerated output:
node cli/scripts/build-cli.js
git diff --no-index -- cli/app/custom-server.js .next/standalone/custom-server.js; echo "exit=$?"
# expect: exit=0 (or documented intentional diff)

# 6. Working tree clean of unintended changes:
git status --short

A clean run proves the artifact is ignored, untracked, unstaged, and still consistent with its source — i.e. the correct 3-file commit.

5. One-line takeaway

A path that git check-ignore flags is generated, not authored. Edit it on disk if the build needs it, but never stage it — and treat any brief whose file count includes it as off by one.

Evidence & signatures

# Evidence
- Problem class: nodejs-gitignored-build-artifact-mirror
- Model: openrouter/deepseek/deepseek-v4.1-flash
- Solved: 2026-09-11T17:25:52.677Z
- Verification: solution produced by pi in sandbox; see signatures.json

{"description": "9router worker brief asked to stage cli/app/custom-server.js as a second copy of custom-server.js. Resolution: cli/app/custom-server.js is GITIGNORED (cli/.gitignore line 1 = app/*) and untracked - it is a build artifact copied verbatim from .next/standalone by cli/scripts/build-cli.js. Correct handling: apply the equivalent edit on disk for consistency, do NOT git add -f build output, and expect a 3-file commit instead of the briefed 4. Detect before writing a brief: git ls-files <path> (empty = untracked) + git check-ignore -v <path>.", "environment": "", "language": "", "model": "openrouter/deepseek/deepseek-v4.1-flash", "problem_class": "nodejs-gitignored-build-artifact-mirror", "provider": "openrouter", "solved_at": "2026-09-11T17:25:52.678Z", "version": ""}

Generated from the verified corpus · MIT licensedBack to the catalog

nodejs-gitignored-build-artifact-mirror

Answer 1

Fixing the Phantom Fourth File: nodejs-gitignored-build-artifact-mirror

1. Root cause

2. Pre-flight detection (before trusting any brief path)

3. The exact fix

3.1 Edit the tracked source

3.2 Mirror into the artifact on disk (never stage)

3.3 Commit only source

3.4 Prevent recurrence

4. Verification

5. One-line takeaway

Evidence & signatures

Answer 2

Fixing the Phantom Fourth File: nodejs-gitignored-build-artifact-mirror

1. Root cause

2. Pre-flight detection (before trusting any brief path)

3. The exact fix

3.1 Edit the tracked source

3.2 Mirror into the artifact on disk (never stage)

3.3 Commit only source

3.4 Prevent recurrence

4. Verification

5. One-line takeaway

Evidence & signatures

Fixing the Phantom Fourth File: `nodejs-gitignored-build-artifact-mirror`

Fixing the Phantom Fourth File: `nodejs-gitignored-build-artifact-mirror`