http2: cleanup of h2 compat layer, add tests

Remove unnecessary variable assignments, remove unreachable code
pathways, remove path getter and setter, and other very minor
cleanup. Only remove reference to stream on nextTick so that
users and libraries can access it in the finish event.

Fixes: #15313
Refs: expressjs/express#3390

Author: apapirovski

lib/internal/http2/compat.js

@@ -21,9 +21,9 @@ server.listen(0, common.mustCall(function() {
       'foo-bar': 'abc123'
     };
 
+    assert.strictEqual(request.path, undefined);
     assert.strictEqual(request.method, expected[':method']);
     assert.strictEqual(request.scheme, expected[':scheme']);
-    assert.strictEqual(request.path, expected[':path']);
     assert.strictEqual(request.url, expected[':path']);
     assert.strictEqual(request.authority, expected[':authority']);
 
@@ -41,11 +41,6 @@ server.listen(0, common.mustCall(function() {
 
     request.url = '/one';
     assert.strictEqual(request.url, '/one');
-    assert.strictEqual(request.path, '/one');
-
-    request.path = '/two';
-    assert.strictEqual(request.url, '/two');
-    assert.strictEqual(request.path, '/two');
 
     response.on('finish', common.mustCall(function() {
       server.close();

test/parallel/test-http2-compat-serverrequest-headers.js

@@ -15,7 +15,6 @@ server.listen(0, common.mustCall(function() {
   const port = server.address().port;
   server.once('request', common.mustCall(function(request, response) {
     const expected = {
-      statusCode: null,
       version: '2.0',
       httpVersionMajor: 2,
       httpVersionMinor: 0
@@ -24,7 +23,6 @@ server.listen(0, common.mustCall(function() {
     assert.strictEqual(request.closed, false);
     assert.strictEqual(request.code, h2.constants.NGHTTP2_NO_ERROR);
 
-    assert.strictEqual(request.statusCode, expected.statusCode);
     assert.strictEqual(request.httpVersion, expected.version);
     assert.strictEqual(request.httpVersionMajor, expected.httpVersionMajor);
     assert.strictEqual(request.httpVersionMinor, expected.httpVersionMinor);

test/parallel/test-http2-compat-serverrequest.js

@@ -26,7 +26,7 @@ const server = http2.createServer(common.mustCall((req, res) => {
     assert.strictEqual(res.closed, true);
   }));
 
-  if (req.path !== '/') {
+  if (req.url !== '/') {
     nextError = errors.shift();
   }
   res.destroy(nextError);

test/parallel/test-http2-compat-serverresponse-destroy.js

@@ -8,13 +8,18 @@ const assert = require('assert');
 const h2 = require('http2');
 
 // Http2ServerResponse.finished
-
 const server = h2.createServer();
 server.listen(0, common.mustCall(function() {
   const port = server.address().port;
   server.once('request', common.mustCall(function(request, response) {
     response.on('finish', common.mustCall(function() {
+      assert.ok(request.stream !== undefined);
+      assert.ok(response.stream !== undefined);
       server.close();
+      process.nextTick(common.mustCall(() => {
+        assert.strictEqual(request.stream, undefined);
+        assert.strictEqual(response.stream, undefined);
+      }));
     }));
     assert.strictEqual(response.finished, false);
     response.end();

test/parallel/test-http2-compat-serverresponse-finished.js

@@ -42,6 +42,31 @@ server.listen(0, common.mustCall(function() {
     response.removeHeader(denormalised);
     assert.strictEqual(response.hasHeader(denormalised), false);
 
+    common.expectsError(
+      () => response.hasHeader(),
+      {
+        code: 'ERR_INVALID_ARG_TYPE',
+        type: TypeError,
+        message: 'The "name" argument must be of type string'
+      }
+    );
+    common.expectsError(
+      () => response.getHeader(),
+      {
+        code: 'ERR_INVALID_ARG_TYPE',
+        type: TypeError,
+        message: 'The "name" argument must be of type string'
+      }
+    );
+    common.expectsError(
+      () => response.removeHeader(),
+      {
+        code: 'ERR_INVALID_ARG_TYPE',
+        type: TypeError,
+        message: 'The "name" argument must be of type string'
+      }
+    );
+
     [
       ':status',
       ':method',
@@ -70,6 +95,14 @@ server.listen(0, common.mustCall(function() {
       type: TypeError,
       message: 'Value must not be undefined or null'
     }));
+    common.expectsError(
+      () => response.setHeader(), // header name undefined
+      {
+        code: 'ERR_INVALID_ARG_TYPE',
+        type: TypeError,
+        message: 'The "name" argument must be of type string'
+      }
+    );
 
     response.setHeader(real, expectedValue);
     const expectedHeaderNames = [real];

test/parallel/test-http2-compat-serverresponse-headers.js

@@ -22,6 +22,11 @@ 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_STREAM_CLOSED'
+        });
+      }));
     }));
     response.end();
   }));

test/parallel/test-http2-compat-serverresponse-writehead.js

@@ -30,7 +30,7 @@ const testsToRun = Object.keys(encodings).length;
 let testsFinished = 0;
 
 const server = http2.createServer(common.mustCall((req, res) => {
-  const testEncoding = encodings[req.path.slice(1)];
+  const testEncoding = encodings[req.url.slice(1)];
 
   req.on('data', common.mustCall((chunk) => assert.ok(
     Buffer.from(testString, testEncoding).equals(chunk)