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ValidationStop
Missing test detection (Stop)
No source file ships without a test
On every session stop, inspects git diff to list modified source files and checks that a matching test file exists. Fails with the list of uncovered files if tests are missing.
What does the Missing test detection (Stop) hook do?
Missing test detection (Stop) is a Claude Code Stop hook. It fires automatically at that lifecycle event — outside the model, so it can't be skipped or forgotten. No source file ships without a test.
As a Stop hook it runs after the action, reacting to what just happened rather than blocking it. Because it is a deterministic Node.js script, it executes on every matching event without relying on the model to remember — the guarantee that makes agentic workflows safe to automate.
Use cases
- Ensure no business file ships without an associated test
- Integrate a lightweight 'Definition of Done' without running the full test suite
Tags
#tests#missing-tests#definition-of-done#git-diff#coverage
settings.json fragment
{
"hooks": {
"Stop": [
{
"hooks": [
{
"command": "node $CLAUDE_PROJECT_DIR/.claude/hooks/missing-test-detection.mjs",
"type": "command"
}
]
}
]
}
}Script · .claude/hooks/missing-test-detection.mjs
#!/usr/bin/env node
// @hookstack stop-missing-test-detection
import { execSync } from "node:child_process";
// @hookstack stop-missing-test-detection
// Détecte les fichiers sources modifiés sans test correspondant (Stop)
import { existsSync, readFileSync, unlinkSync, writeFileSync } from "node:fs";
import { basename } from "node:path";
import { fileURLToPath } from "node:url";
const pid = process.ppid ?? "unknown";
function defaultExec(cmd) {
try {
return execSync(cmd, { encoding: "utf8", timeout: 10_000 }).trim();
} catch {
return "";
}
}
export function run({
exec = defaultExec,
exists = existsSync,
readFile = readFileSync,
writeFile = writeFileSync,
unlink = unlinkSync,
counterFile = `/tmp/.claude-missing-tests-count-${pid}`,
disableFile = `/tmp/.claude-missing-tests-disabled-${pid}`,
} = {}) {
if (exists(disableFile)) {
process.stderr.write(
`[missing-test-detection] SUSPENDU (≥3 échecs). rm '${disableFile}' pour réactiver.\n`,
);
return { exitCode: 0 };
}
const base = exec("git merge-base origin/main HEAD");
const head = exec("git rev-parse HEAD");
const raw =
base && base !== head
? exec(`git diff --name-only ${base} HEAD`)
: exec("git diff --name-only HEAD");
const missing = [];
for (const f of raw.split("\n").filter(Boolean)) {
if (!/(^|\/)src\/(lib|store|hooks)\/[^/]+\.ts$/.test(f)) continue;
if (/\.(test|spec)\.ts$/.test(f)) continue; // un fichier de test n'exige pas son propre test
if (!exists(f)) continue; // fichier supprimé → pas de test requis
const name = basename(f, ".ts");
const found = exec(
`find src tests -name "${name}.test.ts" -o -name "${name}.spec.ts" 2>/dev/null`,
);
if (!found) missing.push(f);
}
if (!missing.length) {
try {
unlink(counterFile);
} catch {}
process.stderr.write(
"[missing-test-detection] ✓ Aucun fichier source sans test détecté.\n",
);
return { exitCode: 0 };
}
let count = 0;
try {
count = parseInt(readFile(counterFile, "utf8").trim(), 10) || 0;
} catch {}
count++;
writeFile(counterFile, String(count));
let msg = `[FAIL] Tests manquants pour les fichiers modifiés :\n${missing.map((f) => ` - ${f}`).join("\n")}\n→ Créer les fichiers de test correspondants.\n`;
if (count >= 3) {
writeFile(disableFile, "");
msg += `[AUTO-DISABLE] hook suspendu après ${count} échecs. rm '${disableFile}' pour réactiver.\n`;
}
return { exitCode: 2, message: msg };
}
if (process.argv[1] === fileURLToPath(import.meta.url)) {
const result = run();
if (result.message) process.stderr.write(result.message);
process.exit(result.exitCode);
}