Repository: nock/nock (js)

Issue:
Nock delay not working when timeout value defined in agent instead of in request itself
### Please avoid duplicates

- [X] I checked [all open bugs](https://github.com/nock/nock.js/issues?q=is%3Aissue+is%3Aopen+label%3Abug) and none of them matched my problem.

### Reproducible test case

https://runkit.com/codinbox/nock-delay

### Nock Version

13.2.2

### Node Version

16.13.0

### TypeScript Version

_No response_

### What happened?

When using nock to test timeout with .delay() function, if request timeout not set but agent timeout, the delay does not work.

If timeout is define in request options, delay() function works and a timeout is triggered.

Nock does not check agent timeout when request timeout does not exist.

### Would you be interested in contributing a fix?

- [X] yes

Pull request:
fix: delay when timeout is on the Agent
resolves #2296

Patch:
diff --git a/lib/intercepted_request_router.js b/lib/intercepted_request_router.js
index 635a34e..54398f5 100644
--- a/lib/intercepted_request_router.js
+++ b/lib/intercepted_request_router.js
@@ -51,8 +51,12 @@ class InterceptedRequestRouter {
 
     // support setting `timeout` using request `options`
     // https://nodejs.org/docs/latest-v12.x/api/http.html#http_http_request_url_options_callback
-    if (options.timeout) {
-      this.socket.setTimeout(options.timeout)
+    // any timeout in the request options override any timeout in the agent options.
+    // per https://github.com/nodejs/node/pull/21204
+    const timeout =
+      options.timeout || (options.agent && options.agent.options.timeout)
+    if (timeout) {
+      this.socket.setTimeout(timeout)
     }
 
     this.response = new IncomingMessage(this.socket)
diff --git a/lib/playback_interceptor.js b/lib/playback_interceptor.js
index 08ebf45..b42d7cf 100644
--- a/lib/playback_interceptor.js
+++ b/lib/playback_interceptor.js
@@ -79,7 +79,7 @@ class ReadableBuffers extends stream.Readable {
     this.buffers = buffers
   }
 
-  _read(size) {
+  _read(_size) {
     while (this.buffers.length) {
       if (!this.push(this.buffers.shift())) {
         return
@@ -315,7 +315,7 @@ function playbackInterceptor({
 
   // Calling `start` immediately could take the request all the way to the connection delay
   // during a single microtask execution. This setImmediate stalls the playback to ensure the
-  // correct events are emitted first ('socket', 'finish') and any aborts in the in the queue or
+  // correct events are emitted first ('socket', 'finish') and any aborts in the queue or
   // called during a 'finish' listener can be called.
   common.setImmediate(() => {
     if (!common.isRequestDestroyed(req)) {


Test patch:
diff --git a/tests/test_delay.js b/tests/test_delay.js
index e0bbd3b..e276fc3 100644
--- a/tests/test_delay.js
+++ b/tests/test_delay.js
@@ -348,6 +348,46 @@ describe('`delayConnection()`', () => {
     req.end()
   })
 
+  it('emits a timeout - with Agent.timeout', done => {
+    nock('http://example.test').get('/').delayConnection(10000).reply(200, 'OK')
+
+    const onEnd = sinon.spy()
+    const agent = new http.Agent({ timeout: 5000 })
+
+    const req = http.request('http://example.test', { agent }, res => {
+      res.once('end', onEnd)
+    })
+
+    req.on('timeout', function () {
+      expect(onEnd).not.to.have.been.called()
+      done()
+    })
+
+    req.end()
+  })
+
+  it('emits a timeout - options.timeout takes precedence over Agent.timeout', done => {
+    nock('http://example.test').get('/').delayConnection(10000).reply(200, 'OK')
+
+    const onEnd = sinon.spy()
+    const agent = new http.Agent({ timeout: 30000 })
+
+    const req = http.request(
+      'http://example.test',
+      { agent, timeout: 5000 },
+      res => {
+        res.once('end', onEnd)
+      }
+    )
+
+    req.on('timeout', function () {
+      expect(onEnd).not.to.have.been.called()
+      done()
+    })
+
+    req.end()
+  })
+
   it('does not emit a timeout when timeout > delayConnection', done => {
     const responseText = 'okeydoke!'
     const scope = nock('http://example.test')