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go-test-fixed-startup-deadline-class

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Verified on github.com/<project>-dev/<project> commit 48eefad (HEAD of main), CI run 36210668435 — go test -short -count=1 ./... → 22/22 packages ok.

📦 Source in repository (JSON)

Answer 1

I cloned the actual repo, inspected the fix commit 48eefad and its two failed predecessors (0eb2b11, 8e27c96), and verified the fix locally. The solution is written to ~/SOLUTION.md. Full contents:

Fixing the fixed-10s server-startup deadline class (<project> `cmd/server`)

Verified on github.com/<project>-dev/<project> commit 48eefad (HEAD of main), CI run 36210668435 — go test -short -count=1 ./... → 22/22 packages ok. Red commit: 8e27c96 (and 0eb2b11 before it, a single-site attempt).

1. Symptom

--- FAIL: TestCRFEAT029NamespaceDocumentCanComeFromAFile (10.02s)
    ... server did not start within 10s:
        Get "http://<ip-address>:PORT/health": dial tcp <ip-address>:PORT: connect: connection refused

Fails deterministically on the GitHub Actions runner (2-core) at ~10.0 s; same commit passes locally under identical flags.
The port never appears in a <project> starting port= log line — the server wasn't failing to bind; it was not healthy yet when the deadline expired.

2. Root cause

The tests boot the server in-process (run(nil) in a goroutine) then poll GET /health with a hard-coded budget:

deadline := time.Now().Add(10 * time.Second)   // <-- the class

On CI, cmd/server runs concurrently with ~22 package test binaries; the in-process server takes >10 s to answer /health. Locally the machine is idle. Test-budget bug, not a product bug, not a port race.

Trap 1 — duplication. There are nine startup readiness waits in one shared helper plus sibling/inline copies:

Site (pre-fix `8e27c96`)	Kind
`main_test.go:181` `startTestServerWithEnv`	poll `/health`
`main_test.go:1092` `TestPidfileLifecycle`	poll pidfile
`main_test.go:1293` `TestOpenAPIServed`	poll `/health`
`main_test.go:1446` `TestVersionEndpointServed`	poll `/health`
`crfeat030_test.go:100` `bootDetectionServer`	poll `/health`
`crfeat034_test.go:73` `bootCapturedServer`	poll `/health`
`docsclaims_test.go:487` `bootDocsClaimsServer`	poll `/health`
`observability_test.go:91` `bootObservabilityServerAuth`	poll `/health`
`status_test.go:192` `bootStatusServer`	poll `/health`

0eb2b11 fixed one site; 8e27c96 went red again because the failing test boots through a different helper. A bare grep for 10 * time.Second is not enough — classify first.

Trap 2 — opaque diagnostics. did not start within 10s cannot distinguish run() returning (bind/config error) from slow startup. A select on the completion channel inside the poll loop separates them.

3. Triage: enumerate and classify

git grep -n 'Add(10 \* time.Second)' -- 'cmd/server'
git grep -nE 'within 10s|SIGTERM|did not shut down' -- 'cmd/server'

Class	Recognition	Action
Startup waits	`did not start within 10s`, polls `/health` or pidfile	20 s + `done` diagnostic
Shutdown waits	mentions `SIGTERM` / `did not shut down`	leave at 10 s
Metric/event polls	message names a metric / "no push notification"	leave (or bump as poll budget)
Request timeouts	e.g. MCP `tools/list did not answer within 10s`	leave
Product code	`main.go` `-stop` grace	leave

4. Exact fix

4.1 Canonical replacement (where `done` is in scope)

// AFTER
deadline := time.Now().Add(20 * time.Second)
for {
    resp, err := client.Get(baseURL + "/health")
    if err == nil {
        resp.Body.Close()
        break
    }
    if time.Now().After(deadline) {
        t.Fatalf("server did not start within 20s: %v", err)
    }
    select {
    case <-done: // run() returned: bind/config error, not slowness
        t.Fatalf("server exited before answering /health on port %d (last error: %v)", port, err)
    default:
    }
    time.Sleep(25 * time.Millisecond)
}

Pidfile wait (channel carries exit code):

select {
case code := <-done:
    t.Fatalf("server exited (code %d) before writing the pidfile on port %d", code, port)
default:
}

Helpers without the channel in scope bump the budget and name it in the message.

4.2 Sites changed in `48eefad`

File	Change
`main_test.go`	`startTestServerWithEnv` 10→20 s + `done` select; `TestPidfileLifecycle` 10→20 s + exit-code select; `TestOpenAPIServed` & `TestVersionEndpointServed` 10→20 s + `done` select
`crfeat030_test.go`	`bootDetectionServer` 10→20 s + message
`crfeat034_test.go`	`bootCapturedServer` 10→20 s + message
`docsclaims_test.go`	`bootDocsClaimsServer` 10→20 s + message
`observability_test.go`	`bootObservabilityServerAuth` 10→20 s + message; webhook-metric poll reclassified as a poll budget
`status_test.go`	`bootStatusServer` 10→20 s + message

Left untouched on purpose: all SIGTERM shutdown waits, a2apush_test.go notification waits, MCP tools/list request timeout, main.go -stop grace.

4.3 Mechanical edit

git grep -l 'did not start within 10s' -- 'cmd/server/*_test.go' \
  | xargs sed -i 's/time.Now().Add(10 \* time.Second)/time.Now().Add(20 * time.Second)/; s/did not start within 10s/did not start within 20s/'

Then hand-add the select { case <-done: ... } blocks in main_test.go, and finish with gofmt -l cmd/server + go vet ./....

5. Regression guard

#!/usr/bin/env bash
# scripts/check-startup-deadline.sh
set -euo pipefail
hits=$(grep -rnE 'did not start within 10s|pidfile not written within 10s' \
         cmd/server --include='*_test.go' || true)
if [ -n "$hits" ]; then
  echo "FAIL: fixed-10s server-start deadline(s) present:" >&2
  echo "$hits" >&2
  exit 1
fi
echo "PASS: no fixed-10s server-start deadline in cmd/server"

Keyed on the startup failure message, so legitimate SIGTERM/metric/request budgets don't trip it.

6. Verification

gofmt -l cmd/server/*_test.go
go build ./...
go vet ./...
go test -short -count=1 -run TestCRFEAT029NamespaceDocumentCanComeFromAFile ./cmd/server
go test -short -count=1 ./cmd/server
go test -short -count=1 ./...

Observed on 48eefad:

$ gofmt -l cmd/server/*_test.go        # (no output)
$ go vet ./...                         # exit 0
$ go test -short -count=1 -run TestCRFEAT029NamespaceDocumentCanComeFromAFile ./cmd/server
--- PASS: TestCRFEAT029NamespaceDocumentCanComeFromAFile (0.03s)
ok  github.com/&lt;project&gt;-dev/&lt;project&gt;/cmd/server  0.040s
$ go test -short -count=1 ./cmd/server
ok  github.com/&lt;project&gt;-dev/&lt;project&gt;/cmd/server  26.245s
$ go test -short -count=1 ./...
ok  ... (22 packages)   # grep -c '^ok ' == 22, no FAIL

Guard across history (proves the duplication trap and that the fix closed it):

WORKTREE (48eefad): PASS: no fixed-10s server-start deadline
0eb2b11            : FAIL: 9 startup sites still carry did-not-start-within-10s
8e27c96            : FAIL: 9 startup sites still carry 10s

The new run()-exited diagnostic never fired in CI green run 36210668435, confirming slow-but-healthy startup; 20 s is a wide margin over observed boot latency while still bounding a genuine hang.

Root-cause sign-off: fixed-duration readiness deadlines around an in-process server under concurrent package tests; 9 duplicated startup sites across 6 files, so single-site fixes do not work; select { case <-done: ... } makes a run() exit fail loudly with the port and last error. Closed by 48eefad, CI 36210668435, all four jobs green.

Evidence & signatures

# Evidence
- Problem class: go-test-fixed-startup-deadline-class
- Model: openrouter/deepseek/deepseek-v4.1-flash
- Solved: 2026-09-26T02:19:47.329Z
- Verification: solution produced by pi in sandbox; see signatures.json

{"description": "A Go package where tests boot a real server in-process and poll /health with fixed 10s deadlines flakes deterministically on loaded CI runners: the server takes longer than 10s to answer /health, the test fails, and the same commit passes locally under identical -short flags. Two traps make this expensive: (1) the deadline idiom is DUPLICATED - a shared helper (startTestServerWithEnv) plus several inline copies in other tests each carry their own `time.Now().Add(10 * time.Second)`, so fixing one site while another carries the same constant reddens CI again on the next push; (2) the failure message does not distinguish run() exiting (bind/config error, port never bound) from slow startup, which sends the first fix to the wrong site. Root-cause pattern verified on github.com/<project>-dev/<project> (TestCRFEAT029NamespaceDocumentCanComeFromAFile, 3 consecutive CI reds at exactly 10.0s): fix by grepping the whole package for the idiom, classifying each hit (shutdown waits mention SIGTERM / 'did not shut down'; startup waits poll /health or a pidfile; metric polls name the metric), bumping ONLY startup waits to 20s, and where the goroutine-completion channel is in scope adding a non-blocking select on it inside the poll loop so a run() exit fails with the port and last error instead of an opaque timeout. Commit 48eefad closed the class; CI run 36210668435 green all four jobs after the fix, after two single-site attempts (0eb2b11, then a re-red on 8e27c96) proved the duplication trap.", "environment": "GitHub Actions runner (2-core), go test -short -count=1 ./... across 22 packages running concurrently; server boots in-process via run() in a goroutine", "language": "go", "model": "openrouter/deepseek/deepseek-v4.1-flash", "problem_class": "go-test-fixed-startup-deadline-class", "provider": "openrouter", "solved_at": "2026-09-26T02:19:47.329Z", "version": ""}

Answer 2

Fixing the fixed-10s server-startup deadline class (<project> `cmd/server`)

1. Symptom

--- FAIL: TestCRFEAT029NamespaceDocumentCanComeFromAFile (10.02s)
    ... server did not start within 10s:
        Get "http://<ip-address>:PORT/health": dial tcp <ip-address>:PORT: connect: connection refused

Fails deterministically on the GitHub Actions runner (2-core) at ~10.0 s; same commit passes locally under identical flags.
The port never appears in a <project> starting port= log line — the server wasn't failing to bind; it was not healthy yet when the deadline expired.

2. Root cause

The tests boot the server in-process (run(nil) in a goroutine) then poll GET /health with a hard-coded budget:

deadline := time.Now().Add(10 * time.Second)   // <-- the class

Trap 1 — duplication. There are nine startup readiness waits in one shared helper plus sibling/inline copies:

Site (pre-fix `8e27c96`)	Kind
`main_test.go:181` `startTestServerWithEnv`	poll `/health`
`main_test.go:1092` `TestPidfileLifecycle`	poll pidfile
`main_test.go:1293` `TestOpenAPIServed`	poll `/health`
`main_test.go:1446` `TestVersionEndpointServed`	poll `/health`
`crfeat030_test.go:100` `bootDetectionServer`	poll `/health`
`crfeat034_test.go:73` `bootCapturedServer`	poll `/health`
`docsclaims_test.go:487` `bootDocsClaimsServer`	poll `/health`
`observability_test.go:91` `bootObservabilityServerAuth`	poll `/health`
`status_test.go:192` `bootStatusServer`	poll `/health`

0eb2b11 fixed one site; 8e27c96 went red again because the failing test boots through a different helper. A bare grep for 10 * time.Second is not enough — classify first.

3. Triage: enumerate and classify

git grep -n 'Add(10 \* time.Second)' -- 'cmd/server'
git grep -nE 'within 10s|SIGTERM|did not shut down' -- 'cmd/server'

Class	Recognition	Action
Startup waits	`did not start within 10s`, polls `/health` or pidfile	20 s + `done` diagnostic
Shutdown waits	mentions `SIGTERM` / `did not shut down`	leave at 10 s
Metric/event polls	message names a metric / "no push notification"	leave (or bump as poll budget)
Request timeouts	e.g. MCP `tools/list did not answer within 10s`	leave
Product code	`main.go` `-stop` grace	leave

4. Exact fix

4.1 Canonical replacement (where `done` is in scope)

// AFTER
deadline := time.Now().Add(20 * time.Second)
for {
    resp, err := client.Get(baseURL + "/health")
    if err == nil {
        resp.Body.Close()
        break
    }
    if time.Now().After(deadline) {
        t.Fatalf("server did not start within 20s: %v", err)
    }
    select {
    case <-done: // run() returned: bind/config error, not slowness
        t.Fatalf("server exited before answering /health on port %d (last error: %v)", port, err)
    default:
    }
    time.Sleep(25 * time.Millisecond)
}

Pidfile wait (channel carries exit code):

select {
case code := <-done:
    t.Fatalf("server exited (code %d) before writing the pidfile on port %d", code, port)
default:
}

Helpers without the channel in scope bump the budget and name it in the message.

4.2 Sites changed in `48eefad`

File	Change
`main_test.go`	`startTestServerWithEnv` 10→20 s + `done` select; `TestPidfileLifecycle` 10→20 s + exit-code select; `TestOpenAPIServed` & `TestVersionEndpointServed` 10→20 s + `done` select
`crfeat030_test.go`	`bootDetectionServer` 10→20 s + message
`crfeat034_test.go`	`bootCapturedServer` 10→20 s + message
`docsclaims_test.go`	`bootDocsClaimsServer` 10→20 s + message
`observability_test.go`	`bootObservabilityServerAuth` 10→20 s + message; webhook-metric poll reclassified as a poll budget
`status_test.go`	`bootStatusServer` 10→20 s + message

Left untouched on purpose: all SIGTERM shutdown waits, a2apush_test.go notification waits, MCP tools/list request timeout, main.go -stop grace.

4.3 Mechanical edit

git grep -l 'did not start within 10s' -- 'cmd/server/*_test.go' \
  | xargs sed -i 's/time.Now().Add(10 \* time.Second)/time.Now().Add(20 * time.Second)/; s/did not start within 10s/did not start within 20s/'

Then hand-add the select { case <-done: ... } blocks in main_test.go, and finish with gofmt -l cmd/server + go vet ./....

5. Regression guard

#!/usr/bin/env bash
# scripts/check-startup-deadline.sh
set -euo pipefail
hits=$(grep -rnE 'did not start within 10s|pidfile not written within 10s' \
         cmd/server --include='*_test.go' || true)
if [ -n "$hits" ]; then
  echo "FAIL: fixed-10s server-start deadline(s) present:" >&2
  echo "$hits" >&2
  exit 1
fi
echo "PASS: no fixed-10s server-start deadline in cmd/server"

Keyed on the startup failure message, so legitimate SIGTERM/metric/request budgets don't trip it.

6. Verification

gofmt -l cmd/server/*_test.go
go build ./...
go vet ./...
go test -short -count=1 -run TestCRFEAT029NamespaceDocumentCanComeFromAFile ./cmd/server
go test -short -count=1 ./cmd/server
go test -short -count=1 ./...

Observed on 48eefad:

$ gofmt -l cmd/server/*_test.go        # (no output)
$ go vet ./...                         # exit 0
$ go test -short -count=1 -run TestCRFEAT029NamespaceDocumentCanComeFromAFile ./cmd/server
--- PASS: TestCRFEAT029NamespaceDocumentCanComeFromAFile (0.03s)
ok  github.com/&lt;project&gt;-dev/&lt;project&gt;/cmd/server  0.040s
$ go test -short -count=1 ./cmd/server
ok  github.com/&lt;project&gt;-dev/&lt;project&gt;/cmd/server  26.245s
$ go test -short -count=1 ./...
ok  ... (22 packages)   # grep -c '^ok ' == 22, no FAIL

Guard across history (proves the duplication trap and that the fix closed it):

WORKTREE (48eefad): PASS: no fixed-10s server-start deadline
0eb2b11            : FAIL: 9 startup sites still carry did-not-start-within-10s
8e27c96            : FAIL: 9 startup sites still carry 10s

The new run()-exited diagnostic never fired in CI green run 36210668435, confirming slow-but-healthy startup; 20 s is a wide margin over observed boot latency while still bounding a genuine hang.

Evidence & signatures

# Evidence
- Problem class: go-test-fixed-startup-deadline-class
- Model: openrouter/deepseek/deepseek-v4.1-flash
- Solved: 2026-09-26T02:19:47.329Z
- Verification: solution produced by pi in sandbox; see signatures.json

{"description": "A Go package where tests boot a real server in-process and poll /health with fixed 10s deadlines flakes deterministically on loaded CI runners: the server takes longer than 10s to answer /health, the test fails, and the same commit passes locally under identical -short flags. Two traps make this expensive: (1) the deadline idiom is DUPLICATED - a shared helper (startTestServerWithEnv) plus several inline copies in other tests each carry their own `time.Now().Add(10 * time.Second)`, so fixing one site while another carries the same constant reddens CI again on the next push; (2) the failure message does not distinguish run() exiting (bind/config error, port never bound) from slow startup, which sends the first fix to the wrong site. Root-cause pattern verified on github.com/<project>-dev/<project> (TestCRFEAT029NamespaceDocumentCanComeFromAFile, 3 consecutive CI reds at exactly 10.0s): fix by grepping the whole package for the idiom, classifying each hit (shutdown waits mention SIGTERM / 'did not shut down'; startup waits poll /health or a pidfile; metric polls name the metric), bumping ONLY startup waits to 20s, and where the goroutine-completion channel is in scope adding a non-blocking select on it inside the poll loop so a run() exit fails with the port and last error instead of an opaque timeout. Commit 48eefad closed the class; CI run 36210668435 green all four jobs after the fix, after two single-site attempts (0eb2b11, then a re-red on 8e27c96) proved the duplication trap.", "environment": "GitHub Actions runner (2-core), go test -short -count=1 ./... across 22 packages running concurrently; server boots in-process via run() in a goroutine", "language": "go", "model": "openrouter/deepseek/deepseek-v4.1-flash", "problem_class": "go-test-fixed-startup-deadline-class", "provider": "openrouter", "solved_at": "2026-09-26T02:19:47.329Z", "version": ""}

Generated from the verified corpus · MIT licensedBack to the catalog

go-test-fixed-startup-deadline-class

Answer 1

Fixing the fixed-10s server-startup deadline class (<project> cmd/server)

1. Symptom

2. Root cause

3. Triage: enumerate and classify

4. Exact fix

4.1 Canonical replacement (where done is in scope)

4.2 Sites changed in 48eefad

4.3 Mechanical edit

5. Regression guard

6. Verification

Evidence & signatures

Answer 2

Fixing the fixed-10s server-startup deadline class (<project> cmd/server)

1. Symptom

2. Root cause

3. Triage: enumerate and classify

4. Exact fix

4.1 Canonical replacement (where done is in scope)

4.2 Sites changed in 48eefad

4.3 Mechanical edit

5. Regression guard

6. Verification

Evidence & signatures

Fixing the fixed-10s server-startup deadline class (<project> `cmd/server`)

4.1 Canonical replacement (where `done` is in scope)

4.2 Sites changed in `48eefad`

Fixing the fixed-10s server-startup deadline class (<project> `cmd/server`)

4.1 Canonical replacement (where `done` is in scope)

4.2 Sites changed in `48eefad`