child_process: add public API for IPC channel

This commit adds a public channel property to ChildProcess. The
existing _channel property is aliased to the new property, with
the intention of deprecating and removing it in the future.

Fixes: https://github.com/nodejs/node/issues/9313
PR-URL: https://github.com/nodejs/node/pull/9322
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Sam Roberts <vieuxtech@gmail.com>

4 files changed, 8 insertions, 6 deletions

diff --git a/test/parallel/test-child-process-fork-regr-gh-2847.js b/test/parallel/test-child-process-fork-regr-gh-2847.js
index 7b4c262fbd..d985b8b4ac 100644
--- a/test/parallel/test-child-process-fork-regr-gh-2847.js
+++ b/test/parallel/test-child-process-fork-regr-gh-2847.js
@@ -44,8 +44,8 @@ var server = net.createServer(function(s) {
   }
 
   worker.process.once('close', common.mustCall(function() {
-    // Otherwise the crash on `_channel.fd` access may happen
-    assert.strictEqual(worker.process._channel, null);
+    // Otherwise the crash on `channel.fd` access may happen
+    assert.strictEqual(worker.process.channel, null);
     server.close();
   }));
 
diff --git a/test/parallel/test-child-process-fork.js b/test/parallel/test-child-process-fork.js
index 5ae231ef03..a7d4a995a3 100644
--- a/test/parallel/test-child-process-fork.js
+++ b/test/parallel/test-child-process-fork.js
@@ -5,6 +5,8 @@ var fork = require('child_process').fork;
 var args = ['foo', 'bar'];
 
 var n = fork(common.fixturesDir + '/child-process-spawn-node.js', args);
+
+assert.strictEqual(n.channel, n._channel);
 assert.deepStrictEqual(args, ['foo', 'bar']);
 
 n.on('message', function(m) {
diff --git a/test/parallel/test-child-process-recv-handle.js b/test/parallel/test-child-process-recv-handle.js
index 5257c46b54..e69cd68d33 100644
--- a/test/parallel/test-child-process-recv-handle.js
+++ b/test/parallel/test-child-process-recv-handle.js
@@ -36,12 +36,12 @@ function master() {
 }
 
 function worker() {
-  process._channel.readStop();  // Make messages batch up.
+  process.channel.readStop();  // Make messages batch up.
   process.stdout.ref();
   process.stdout.write('ok\r\n');
   process.stdin.once('data', common.mustCall((data) => {
     assert.strictEqual(data.toString(), 'ok\r\n');
-    process._channel.readStart();
+    process.channel.readStart();
   }));
   let n = 0;
   process.on('message', common.mustCall((msg, handle) => {
diff --git a/test/parallel/test-child-process-silent.js b/test/parallel/test-child-process-silent.js
index ce5e28cc32..50d4ae881a 100644
--- a/test/parallel/test-child-process-silent.js
+++ b/test/parallel/test-child-process-silent.js
@@ -21,8 +21,8 @@ if (process.argv[2] === 'pipe') {
   const child = childProcess.fork(process.argv[1], ['pipe'], {silent: true});
 
   // Allow child process to self terminate
-  child._channel.close();
-  child._channel = null;
+  child.channel.close();
+  child.channel = null;
 
   child.on('exit', function() {
     process.exit(0);