signals: ignore them

signals are passed to the spawned child process; this means
that the main process should not react to them, and instead
wait for the spawned process to exit as a result of receiving
the forwarded signal.

src/bin.ts

@@ -57,13 +57,15 @@ v8flags(function (err, v8flags) {
     { stdio: 'inherit' }
   )
 
-  proc.on('exit', function (code: number, signal: string) {
-    process.on('exit', function () {
-      if (signal) {
-        process.kill(process.pid, signal)
-      } else {
-        process.exit(code)
-      }
-    })
-  })
+  // Ignore the following signals; the child process will be receiving them,
+  // and should exit by itself
+  process.on('SIGINT', () => proc.kill('SIGINT'))
+  process.on('SIGTERM', () => proc.kill('SIGTERM'))
+
+  // On exit, exit this process with the same exit code
+  proc.on('exit', (code: number) => process.exit(code))
+
+  // If this process is exited with any other signals,
+  // kill the subprocess with the same signal
+  process.on('exit', (_code: number, signal: string) => proc.kill(signal))
 })

src/index.spec.ts

@@ -20,6 +20,21 @@ describe('ts-node', function () {
   })
 
   describe('cli', function () {
+    this.slow(1000)
+
+    it('should not react to signals, but forward them to the child process', function (done) {
+      const proc = exec(`${BIN_EXEC} tests/signals`, function (err, stdout) {
+        expect(err).to.equal(null)
+        expect(stdout).to.equal('exited\n')
+
+        return done()
+      })
+
+      // Leave enough time for node to fully start
+      // the process, then send a signal
+      setTimeout(() => proc.kill('SIGINT'), 1000)
+    })
+
     it('should execute cli', function (done) {
       exec(`${BIN_EXEC} tests/hello-world`, function (err, stdout) {
         expect(err).to.equal(null)

tests/signals.ts

@@ -0,0 +1,8 @@
+process.on('SIGINT', () => {
+  setTimeout(() => {
+    console.log('exited')
+    process.exit(0)
+  }, 2000)
+})
+
+setInterval(() => console.log('should not be reached'), 4000)