From aa2cba8e0379dcd27d5017507ba4c0d3165cbe8d Mon Sep 17 00:00:00 2001
From: Anton Frattaroli <frattaro@gmail.com>
Date: Fri, 12 Jul 2024 17:07:48 -0400
Subject: [PATCH] feat: add watchdog pid as cleanup metadata arg

PR-URL: https://github.com/tapjs/foreground-child/pull/59
Credit: @frattaro
Close: #59
Reviewed-by: @isaacs
---
 CHANGELOG.md              |  5 +++++
 src/index.ts              | 10 ++++++++--
 test/normalize-fg-args.ts |  2 +-
 3 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3d284a9..649f270 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # Changes
 
+## v3.3
+
+- Include `watchdogPid` as a metadata argument to cleanup
+  function
+
 ## v3.2
 
 - Export `watchdog` and `proxySignals` functionality
diff --git a/src/index.ts b/src/index.ts
index 9e84fed..d807126 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -4,6 +4,7 @@ import {
   Serializable,
   spawn as nodeSpawn,
   SpawnOptions,
+  ChildProcess,
 } from 'child_process'
 import crossSpawn from 'cross-spawn'
 import { onExit } from 'signal-exit'
@@ -37,6 +38,9 @@ const spawn = process?.platform === 'win32' ? crossSpawn : nodeSpawn
 export type Cleanup = (
   code: number | null,
   signal: null | NodeJS.Signals,
+  processInfo: {
+    watchdogPid?: ChildProcess['pid']
+  },
 ) =>
   | void
   | undefined
@@ -159,7 +163,7 @@ export function foregroundChild(
   const removeOnExit = onExit(childHangup)
 
   proxySignals(child)
-  watchdog(child)
+  const dog = watchdog(child)
 
   let done = false
   child.on('close', async (code, signal) => {
@@ -167,7 +171,9 @@ export function foregroundChild(
     if (done) return
     /* c8 ignore stop */
     done = true
-    const result = cleanup(code, signal)
+    const result = cleanup(code, signal, {
+      watchdogPid: dog.pid,
+    })
     const res = isPromise(result) ? await result : result
     removeOnExit()
 
diff --git a/test/normalize-fg-args.ts b/test/normalize-fg-args.ts
index aee0280..698ad81 100644
--- a/test/normalize-fg-args.ts
+++ b/test/normalize-fg-args.ts
@@ -32,7 +32,7 @@ t.plan(cases.length)
 for (const c of cases) {
   t.test(JSON.stringify(c), t => {
     const norm = normalizeFgArgs(c)
-    norm[3](0, null)
+    norm[3](0, null, {})
     t.equal(norm[0], 'cmd')
     if (Array.isArray(c[1])) {
       t.equal(norm[1], c[1])