From 04c715fdf5f5aeaee913f24c276755dbc3f45501 Mon Sep 17 00:00:00 2001
From: Matteo Collina <hello@matteocollina.com>
Date: Mon, 13 May 2019 19:41:48 +0200
Subject: [PATCH] http2: do no throw in writeHead if state.closed

The http1 implementation does not throw if the connection is down.
The http2 compat implementation should do the same.

See: https://github.com/fastify/fastify-http-proxy/issues/51.
See: https://github.com/fastify/fastify/issues/1494.
---
 lib/internal/http2/compat.js                               | 7 ++-----
 .../parallel/test-http2-compat-serverresponse-writehead.js | 6 +++---
 2 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/lib/internal/http2/compat.js b/lib/internal/http2/compat.js
index 37f8242b0068f3..516954587108a8 100644
--- a/lib/internal/http2/compat.js
+++ b/lib/internal/http2/compat.js
@@ -589,14 +589,11 @@ class Http2ServerResponse extends Stream {
   writeHead(statusCode, statusMessage, headers) {
     const state = this[kState];
 
-    if (state.closed)
-      throw new ERR_HTTP2_INVALID_STREAM();
+    if (state.closed || this.stream.destroyed)
+      return this;
     if (this[kStream].headersSent)
       throw new ERR_HTTP2_HEADERS_SENT();
 
-    if (this.stream.destroyed)
-      return this;
-
     if (typeof statusMessage === 'string')
       statusMessageWarn();
 
diff --git a/test/parallel/test-http2-compat-serverresponse-writehead.js b/test/parallel/test-http2-compat-serverresponse-writehead.js
index aabcf18ad9e0cf..e66f5f79cd9041 100644
--- a/test/parallel/test-http2-compat-serverresponse-writehead.js
+++ b/test/parallel/test-http2-compat-serverresponse-writehead.js
@@ -26,9 +26,9 @@ server.listen(0, common.mustCall(function() {
     response.on('finish', common.mustCall(function() {
       server.close();
       process.nextTick(common.mustCall(() => {
-        common.expectsError(() => { response.writeHead(300); }, {
-          code: 'ERR_HTTP2_INVALID_STREAM'
-        });
+        // The stream is invalid at this point,
+        // and this line verifies this does not throw.
+        response.writeHead(300);
       }));
     }));
     response.end();