Tie IPC stream lifecycle to process lifecycle

Fixes #1

Author: kasperisager

index.js

@@ -15,9 +15,11 @@ module.exports = class Sidecar extends Duplex {
       stdio: ['pipe', 'pipe', 'pipe', 'overlapped']
     })
 
+    this._process.on('close', this._onclose.bind(this)).on('exit', this._onexit.bind(this))
+
     const ipc = this._process.stdio[3]
 
-    this._ipc = ipc.on('end', () => ipc.end())
+    this._ipc = ipc.on('end', this._onend.bind(this))
   }
 
   get stdin() {
@@ -42,4 +44,22 @@ module.exports = class Sidecar extends Duplex {
   _write(chunk, encoding, cb) {
     this._ipc.write(chunk, encoding, cb)
   }
+
+  _predestroy() {
+    this._process.kill()
+  }
+
+  _onend() {
+    this._ipc.end()
+
+    this.push(null)
+  }
+
+  _onclose() {
+    this.end()
+  }
+
+  _onexit(code, status) {
+    this.emit('exit', code, status)
+  }
 }

lib/runtime.js

@@ -6,6 +6,30 @@ const path = require('bare-path')
 
 const ipc = new Pipe(3)
 
+ipc.on('newListener', onnewlistener).on('removeListener', onremovelistener).on('close', onclose)
+
+function onnewlistener(name, fn) {
+  if (fn === onremovelistener || fn === onclose) return
+
+  switch (name) {
+    case 'close':
+      ipc.off(name, onclose)
+  }
+}
+
+function onremovelistener(name, fn) {
+  if (fn === onremovelistener || fn === onclose) return
+
+  switch (name) {
+    case 'close':
+      if (ipc.listenerCount(name) === 0) ipc.on(name, onclose)
+  }
+}
+
+function onclose() {
+  Bare.exit()
+}
+
 Bare.IPC = ipc.unref()
 
 const parentURL = url.pathToFileURL(os.cwd())

test.js

@@ -8,3 +8,64 @@ test('basic', (t) => {
 
   sidecar.on('data', (data) => t.is(data.toString(), 'Hello world')).write('Hello world')
 })
+
+test('kill on destroy', (t) => {
+  t.plan(3)
+
+  const sidecar = new Sidecar(require.resolve('./test/fixtures/sleep'))
+
+  sidecar
+    .on('exit', (code, status) => {
+      t.is(code, 0)
+      t.not(status, 0)
+    })
+    .on('close', () => {
+      t.pass('closed')
+    })
+    .destroy()
+})
+
+test('exit on ipc close', (t) => {
+  t.plan(3)
+
+  const sidecar = new Sidecar(require.resolve('./test/fixtures/ipc-close'))
+
+  sidecar
+    .on('exit', (code, status) => {
+      t.is(code, 0)
+      t.is(status, 0)
+    })
+    .on('close', () => {
+      t.pass('closed')
+    })
+})
+
+test('exit on ipc destroy', (t) => {
+  t.plan(3)
+
+  const sidecar = new Sidecar(require.resolve('./test/fixtures/ipc-destroy'))
+
+  sidecar
+    .on('exit', (code, status) => {
+      t.is(code, 0)
+      t.is(status, 0)
+    })
+    .on('close', () => {
+      t.pass('closed')
+    })
+})
+
+test('uncaught throw', (t) => {
+  t.plan(3)
+
+  const sidecar = new Sidecar(require.resolve('./test/fixtures/throw'))
+
+  sidecar
+    .on('exit', (code, status) => {
+      t.is(code, 0)
+      t.not(status, 0)
+    })
+    .on('close', () => {
+      t.pass('closed')
+    })
+})

test/fixtures/ipc-close.js

@@ -0,0 +1,5 @@
+Bare.IPC.end()
+
+setTimeout(() => {
+  throw new Error('Abort')
+}, 60000)

test/fixtures/ipc-destroy.js

@@ -0,0 +1,5 @@
+Bare.IPC.destroy()
+
+setTimeout(() => {
+  throw new Error('Abort')
+}, 60000)

test/fixtures/sleep.js

@@ -0,0 +1 @@
+setTimeout(() => {}, 60000)

test/fixtures/throw.js

@@ -0,0 +1 @@
+throw new Error('Abort')