http2: near full http1 compatibility, add tests

Extensive re-work of http1 compatibility layer based on tests in
express, on-finished and finalhandler. Fix handling of HEAD
method to match http1. Adjust write, end, etc. to call writeHead
as in http1 and as expected by user-land modules. Add socket
proxy that instead uses the Http2Stream for the vast majority of
socket interactions. Add and change tests to closer represent
http1 behaviour.

Refs: https://github.com/nodejs/node/pull/15633
Refs: https://github.com/expressjs/express/tree/master/test
Refs: https://github.com/jshttp/on-finished/blob/master/test/test.js
Refs: https://github.com/pillarjs/finalhandler/blob/master/test/test.js
PR-URL: https://github.com/nodejs/node/pull/15702
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/test/parallel/test-http2-compat-serverresponse-flushheaders.js b/test/parallel/test-http2-compat-serverresponse-flushheaders.js
index 48bf4dd2d4..68d4789f69 100644
--- a/test/parallel/test-http2-compat-serverresponse-flushheaders.js
+++ b/test/parallel/test-http2-compat-serverresponse-flushheaders.js
@@ -15,18 +15,23 @@ server.listen(0, common.mustCall(function() {
   const port = server.address().port;
   server.once('request', common.mustCall(function(request, response) {
     assert.strictEqual(response.headersSent, false);
+    assert.strictEqual(response._header, false); // alias for headersSent
     response.flushHeaders();
     assert.strictEqual(response.headersSent, true);
+    assert.strictEqual(response._header, true);
     response.flushHeaders(); // Idempotent
 
     common.expectsError(() => {
       response.writeHead(400, { 'foo-bar': 'abc123' });
     }, {
-      code: 'ERR_HTTP2_INFO_HEADERS_AFTER_RESPOND'
+      code: 'ERR_HTTP2_HEADERS_SENT'
     });
 
     response.on('finish', common.mustCall(function() {
       server.close();
+      process.nextTick(() => {
+        response.flushHeaders(); // Idempotent
+      });
     }));
     serverResponse = response;
   }));