From a4e923f5c13b80bf43ecfca4e9be483535011dbe Mon Sep 17 00:00:00 2001
From: Anatoli Papirovski <apapirovski@mac.com>
Date: Thu, 14 Sep 2017 14:02:54 -0400
Subject: [PATCH] http2: fix subsequent end calls to not throw

Calling Http2ServerResponse.end multiple times should never
cause the code to throw an error, subsequent calls should
instead return false. Fix behaviour to match http1.

Fixes: https://github.com/nodejs/node/issues/15385
PR-URL: https://github.com/nodejs/node/pull/15414
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
---
 lib/internal/http2/compat.js                          | 7 +++----
 test/parallel/test-http2-compat-serverresponse-end.js | 5 ++++-
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/lib/internal/http2/compat.js b/lib/internal/http2/compat.js
index 04f4bb3c5a3..e2bbab26d0f 100644
--- a/lib/internal/http2/compat.js
+++ b/lib/internal/http2/compat.js
@@ -458,14 +458,13 @@ class Http2ServerResponse extends Stream {
       cb = encoding;
       encoding = 'utf8';
     }
+    if (stream === undefined || stream.finished === true) {
+      return false;
+    }
     if (chunk !== null && chunk !== undefined) {
       this.write(chunk, encoding);
     }
 
-    if (stream === undefined) {
-      return;
-    }
-
     if (typeof cb === 'function') {
       stream.once('finish', cb);
     }
diff --git a/test/parallel/test-http2-compat-serverresponse-end.js b/test/parallel/test-http2-compat-serverresponse-end.js
index 6c07f6d83e6..92a0fab4e0a 100644
--- a/test/parallel/test-http2-compat-serverresponse-end.js
+++ b/test/parallel/test-http2-compat-serverresponse-end.js
@@ -4,7 +4,7 @@
 const { mustCall, mustNotCall, hasCrypto, skip } = require('../common');
 if (!hasCrypto)
   skip('missing crypto');
-const { strictEqual } = require('assert');
+const { doesNotThrow, strictEqual } = require('assert');
 const {
   createServer,
   connect,
@@ -19,6 +19,9 @@ const {
   // but may be invoked repeatedly without throwing errors.
   const server = createServer(mustCall((request, response) => {
     strictEqual(response.closed, false);
+    response.on('finish', mustCall(() => process.nextTick(
+      mustCall(() => doesNotThrow(() => response.end('test', mustNotCall())))
+    )));
     response.end(mustCall(() => {
       server.close();
     }));