test(debugger): enforce teardown process isolation (#7660)

watson · web-flow · commit 2c69381f90a8 · 2026-03-04T10:37:31.000-08:00
* test(debugger): enforce teardown process isolation

Wait for the debugger target app to exit in `afterEach` before
stopping the fake agent and starting the next test.

Use a bounded SIGTERM wait with a SIGKILL fallback, and fail
explicitly if the child still does not exit, to prevent cross-test
span leakage.

* test(integration): share process stop helper

Move robust child-process teardown into `integration-tests/helpers`
as `stopProc` and use it in debugger test utils.

This centralizes SIGTERM/SIGKILL shutdown handling and helps
prevent cross-test leakage from lingering processes.
diff --git a/integration-tests/debugger/utils.js b/integration-tests/debugger/utils.js
@@ -9,7 +9,7 @@ const { randomUUID } = require('crypto')
 const Axios = require('axios')
 
 const { assertObjectContains, assertUUID } = require('../helpers')
-const { sandboxCwd, useSandbox, FakeAgent, spawnProc } = require('../helpers')
+const { sandboxCwd, useSandbox, FakeAgent, spawnProc, stopProc } = require('../helpers')
 const { generateProbeConfig } = require('../../packages/dd-trace/test/debugger/devtools_client/utils')
 const { version } = require('../../package.json')
 
@@ -222,7 +222,7 @@ function setup ({ env, testApp, testAppSource, dependencies, silent, stdioHandle
   })
 
   afterEach(async function () {
-    t.proc?.kill()
+    await stopProc(t.proc)
     await t.agent?.stop()
   })
 
diff --git a/integration-tests/helpers/index.js b/integration-tests/helpers/index.js
@@ -28,6 +28,7 @@ let shouldKill
 const ANY_STRING = Symbol('test.ANY_STRING')
 const ANY_NUMBER = Symbol('test.ANY_NUMBER')
 const ANY_VALUE = Symbol('test.ANY_VALUE')
+const defaultStopProcTimeoutMs = 2_000
 
 /**
  * @param {string} filename
@@ -65,7 +66,7 @@ async function runAndCheckOutput (filename, cwd, expectedOut, expectedSource) {
 
   if (expectedSource) {
     assert.match(out, new RegExp(`instrumentation source: ${expectedSource}`),
-    `Expected the process to output "${expectedSource}", but logs only contain: "${out}"`)
+      `Expected the process to output "${expectedSource}", but logs only contain: "${out}"`)
   }
   return pid
 }
@@ -261,6 +262,60 @@ function spawnProcAndExpectExit (filename, options = {}, stdioHandler, stderrHan
   })
 }
 
+/**
+ * Stop a process and wait for it to fully exit.
+ *
+ * Sends `SIGTERM` first, waits up to `timeoutMs`, and escalates to `SIGKILL` if needed.
+ *
+ * @param {childProcess.ChildProcess|undefined} proc - Process to stop.
+ * @param {object} [options] - Stop options.
+ * @param {number} [options.timeoutMs=defaultStopProcTimeoutMs] - Max wait per signal in milliseconds.
+ * @returns {Promise<void>}
+ */
+async function stopProc (proc, { timeoutMs = defaultStopProcTimeoutMs } = {}) {
+  if (!proc) return
+  if (proc.exitCode !== null || proc.signalCode !== null) return
+
+  proc.kill()
+
+  const exitedAfterSigterm = await waitForProcExit(proc, timeoutMs)
+  if (exitedAfterSigterm) return
+
+  proc.kill('SIGKILL')
+  const exitedAfterSigkill = await waitForProcExit(proc, timeoutMs)
+
+  if (!exitedAfterSigkill) {
+    throw new Error(`Process ${proc.pid} did not exit after SIGKILL`)
+  }
+}
+
+/**
+ * Wait for a process to exit for up to `timeoutMs`.
+ *
+ * @param {childProcess.ChildProcess} proc - Process to wait for.
+ * @param {number} timeoutMs - Max time to wait in milliseconds.
+ * @returns {Promise<boolean>} `true` if the process exited before timeout.
+ */
+function waitForProcExit (proc, timeoutMs) {
+  if (proc.exitCode !== null || proc.signalCode !== null) {
+    return Promise.resolve(true)
+  }
+
+  return new Promise((resolve) => {
+    const timeout = setTimeout(() => {
+      proc.removeListener('exit', onExit)
+      resolve(false)
+    }, timeoutMs)
+
+    proc.once('exit', onExit)
+
+    function onExit () {
+      clearTimeout(timeout)
+      resolve(true)
+    }
+  })
+}
+
 /**
  * Internal implementation for spawnProc and spawnProcAndAllowExit.
  *
@@ -954,6 +1009,7 @@ module.exports = {
   hookFile,
   assertObjectContains,
   assertUUID,
+  stopProc,
   spawnProc,
   spawnProcAndExpectExit,
   telemetryForwarder,
