http2: add edge case note to GOAWAY request

doc/api/http2.md

@@ -922,6 +922,12 @@ For HTTP/2 Client `Http2Session` instances only, the `http2session.request()`
 creates and returns an `Http2Stream` instance that can be used to send an
 HTTP/2 request to the connected server.
 
+When a `ClientHttp2Session` is first created, the socket may not yet be
+connected. if `clienthttp2session.request()` is called during this time, the
+actual request will be deferred until the socket is ready to go.
+If the `session` is closed before the actual request be executed, an
+`ERR_HTTP2_GOAWAY_SESSION` is thrown.
+
 This method is only available if `http2session.type` is equal to
 `http2.constants.NGHTTP2_SESSION_CLIENT`.
 

test/parallel/test-http2-goaway-delayed-request.js

@@ -0,0 +1,22 @@
+'use strict';
+
+const common = require('../common');
+if (!common.hasCrypto)
+  common.skip('missing crypto');
+
+const http2 = require('http2');
+
+const server = http2.createServer();
+
+server.listen(0, () => {
+  const client = http2.connect(`http://localhost:${server.address().port}`);
+  client.on('close', common.mustCall(() => {
+    server.close();
+  }));
+
+  // The client.close() is executed before the socket is able to make request
+  const stream = client.request();
+  stream.on('error', common.expectsError({ code: 'ERR_HTTP2_GOAWAY_SESSION' }));
+
+  setImmediate(() => client.close());
+});