fix: implement child_process IPC (#21490)

This PR implements the Node child_process IPC functionality in Deno on
Unix systems.

For `fd > 2` a duplex unix pipe is set up between the parent and child
processes. Currently implements data passing via the channel in the JSON
serialization format.

cli/args/mod.rs

@@ -939,6 +939,17 @@ impl CliOptions {
     .map(Some)
   }
 
+  pub fn node_ipc_fd(&self) -> Option<i32> {
+    let maybe_node_channel_fd = std::env::var("DENO_CHANNEL_FD").ok();
+    if let Some(node_channel_fd) = maybe_node_channel_fd {
+      // Remove so that child processes don't inherit this environment variable.
+      std::env::remove_var("DENO_CHANNEL_FD");
+      node_channel_fd.parse::<i32>().ok()
+    } else {
+      None
+    }
+  }
+
   pub fn resolve_main_module(&self) -> Result<ModuleSpecifier, AnyError> {
     match &self.flags.subcommand {
       DenoSubcommand::Bundle(bundle_flags) => {

cli/factory.rs

@@ -672,6 +672,7 @@ impl CliFactory {
       self.maybe_lockfile().clone(),
       self.feature_checker().clone(),
       self.create_cli_main_worker_options()?,
+      self.options.node_ipc_fd(),
     ))
   }
 

cli/standalone/mod.rs

@@ -530,6 +530,7 @@ pub async fn run(
       unstable: metadata.unstable,
       maybe_root_package_json_deps: package_json_deps_provider.deps().cloned(),
     },
+    None,
   );
 
   v8_set_flags(construct_v8_flags(&[], &metadata.v8_flags, vec![]));

cli/tests/node_compat/config.jsonc

@@ -38,6 +38,10 @@
       "test-child-process-execfile.js",
       "test-child-process-execsync-maxbuf.js",
       "test-child-process-exit-code.js",
+      // TODO(littledivy): windows ipc streams not yet implemented
+      "test-child-process-fork-ref.js",
+      "test-child-process-fork-ref2.js",
+      "test-child-process-ipc-next-tick.js",
       "test-child-process-ipc.js",
       "test-child-process-spawnsync-env.js",
       "test-child-process-stdio-inherit.js",
@@ -109,9 +113,7 @@
       "test-zlib-zero-windowBits.js"
     ],
     "pummel": [],
-    "sequential": [
-      "test-child-process-exit.js"
-    ]
+    "sequential": ["test-child-process-exit.js"]
   },
   "tests": {
     "common": [
@@ -138,11 +140,7 @@
       "print-chars.js",
       "x.txt"
     ],
-    "fixtures/keys": [
-      "agent1-cert.pem",
-      "agent1-key.pem",
-      "ca1-cert.pem"
-    ],
+    "fixtures/keys": ["agent1-cert.pem", "agent1-key.pem", "ca1-cert.pem"],
     "internet": [
       "test-dns-any.js",
       "test-dns-idna2008.js",
@@ -695,9 +693,7 @@
       "test-tty-stdout-end.js"
     ],
     "pummel": [],
-    "sequential": [
-      "test-child-process-exit.js"
-    ]
+    "sequential": ["test-child-process-exit.js"]
   },
   "windowsIgnore": {
     "parallel": [

cli/tests/node_compat/test/parallel/test-child-process-fork-ref.js

@@ -0,0 +1,72 @@
+// deno-fmt-ignore-file
+// deno-lint-ignore-file
+
+// Copyright Joyent and Node contributors. All rights reserved. MIT license.
+// Taken from Node 18.12.1
+// This file is automatically generated by `tools/node_compat/setup.ts`. Do not modify this file manually.
+
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+'use strict';
+
+// Ignore on Windows.
+if (process.platform === 'win32') {
+  process.exit(0);
+}
+
+require('../common');
+const assert = require('assert');
+const fork = require('child_process').fork;
+
+if (process.argv[2] === 'child') {
+  process.send('1');
+
+  // Check that child don't instantly die
+  setTimeout(function() {
+    process.send('2');
+  }, 200);
+
+  process.on('disconnect', function() {
+    process.stdout.write('3');
+  });
+
+} else {
+  const child = fork(__filename, ['child'], { silent: true });
+
+  const ipc = [];
+  let stdout = '';
+
+  child.on('message', function(msg) {
+    ipc.push(msg);
+
+    if (msg === '2') child.disconnect();
+  });
+
+  child.stdout.on('data', function(chunk) {
+    stdout += chunk;
+  });
+
+  child.once('exit', function() {
+    assert.deepStrictEqual(ipc, ['1', '2']);
+    assert.strictEqual(stdout, '3');
+  });
+}