Prefix node built-in module imports with node:.

This makes the imports diistinguishable from the corresponding `npm` packages, which can help with:

- Development ergonomics:
  - Marking all `node:*` packages as external in a bundler.
  - Tracking the dependency graph
- Supply chain security (avoiding risks from name squatting).

The `node:` protocol prefix is supported in LTS versions all the way back to `node` 12: https://nodejs.org/api/esm.html#node-imports

Author: lgarron

src/lib/libatomic.js

@@ -153,7 +153,7 @@ addToLibrary({
 
   emscripten_num_logical_cores: () =>
 #if ENVIRONMENT_MAY_BE_NODE
-    ENVIRONMENT_IS_NODE ? require('os').cpus().length :
+    ENVIRONMENT_IS_NODE ? require('node:os').cpus().length :
 #endif
     navigator['hardwareConcurrency'],
 });

src/lib/libcore.js

@@ -352,7 +352,7 @@ addToLibrary({
       var cmdstr = UTF8ToString(command);
       if (!cmdstr.length) return 0; // this is what glibc seems to do (shell works test?)
 
-      var cp = require('child_process');
+      var cp = require('node:child_process');
       var ret = cp.spawnSync(cmdstr, [], {shell:true, stdio:'inherit'});
 
       var _W_EXITCODE = (ret, sig) => ((ret) << 8 | (sig));

src/lib/libsockfs.js

@@ -208,7 +208,7 @@ addToLibrary({
             var WebSocketConstructor;
 #if ENVIRONMENT_MAY_BE_NODE
             if (ENVIRONMENT_IS_NODE) {
-              WebSocketConstructor = /** @type{(typeof WebSocket)} */(require('ws'));
+              WebSocketConstructor = /** @type{(typeof WebSocket)} */(require('node:ws'));
             } else
 #endif // ENVIRONMENT_MAY_BE_NODE
             {
@@ -503,7 +503,7 @@ addToLibrary({
         if (sock.server) {
            throw new FS.ErrnoError({{{ cDefs.EINVAL }}});  // already listening
         }
-        var WebSocketServer = require('ws').Server;
+        var WebSocketServer = require('node:ws').Server;
         var host = sock.saddr;
 #if SOCKET_DEBUG
         dbg(`websocket: listen: ${host}:${sock.sport}`);

src/lib/libwasi.js

@@ -564,7 +564,7 @@ var WasiLibrary = {
 #if ENVIRONMENT_MAY_BE_NODE && MIN_NODE_VERSION < 190000
     // This block is not needed on v19+ since crypto.getRandomValues is builtin
     if (ENVIRONMENT_IS_NODE) {
-      var nodeCrypto = require('crypto');
+      var nodeCrypto = require('node:crypto');
       return (view) => nodeCrypto.randomFillSync(view);
     }
 #endif // ENVIRONMENT_MAY_BE_NODE

src/lib/libwasm_worker.js

@@ -286,7 +286,7 @@ if (ENVIRONMENT_IS_WASM_WORKER
 
   emscripten_navigator_hardware_concurrency: () => {
 #if ENVIRONMENT_MAY_BE_NODE
-    if (ENVIRONMENT_IS_NODE) return require('os').cpus().length;
+    if (ENVIRONMENT_IS_NODE) return require('node:os').cpus().length;
 #endif
     return navigator['hardwareConcurrency'];
   },

src/preamble.js

@@ -654,7 +654,7 @@ function instantiateSync(file, info) {
   var binary = getBinarySync(file);
 #if NODE_CODE_CACHING
   if (ENVIRONMENT_IS_NODE) {
-    var v8 = require('v8');
+    var v8 = require('node:v8');
     // Include the V8 version in the cache name, so that we don't try to
     // load cached code from another version, which fails silently (it seems
     // to load ok, but we do actually recompile the binary every time).

src/proxyClient.js

@@ -18,7 +18,7 @@
 #if ENVIRONMENT_MAY_BE_NODE
 var ENVIRONMENT_IS_NODE = typeof process == 'object' && typeof process.versions == 'object' && typeof process.versions.node == 'string' && process.type != 'renderer';
 if (ENVIRONMENT_IS_NODE) {
-  var NodeWorker = require('worker_threads').Worker;
+  var NodeWorker = require('node:worker_threads').Worker;
   global.Worker = function(url, options) {
     // Special handling for `data:` URL argument, to match the behaviour
     // of the Web API.

src/runtime_shared.js

@@ -91,6 +91,6 @@ if (ENVIRONMENT_IS_NODE) {
   // depends on it for accurate timing.
   // Use `global` rather than `globalThis` here since older versions of node
   // don't have `globalThis`.
-  global.performance ??= require('perf_hooks').performance;
+  global.performance ??= require('node:perf_hooks').performance;
 }
 #endif

src/shell.js

@@ -103,13 +103,13 @@ if (ENVIRONMENT_IS_NODE) {
 #if EXPORT_ES6
   // When building an ES module `require` is not normally available.
   // We need to use `createRequire()` to construct the require()` function.
-  const { createRequire } = await import('module');
+  const { createRequire } = await import('node:module');
   /** @suppress{duplicate} */
   var require = createRequire(import.meta.url);
 #endif
 
 #if PTHREADS || WASM_WORKERS
-  var worker_threads = require('worker_threads');
+  var worker_threads = require('node:worker_threads');
   global.Worker = worker_threads.Worker;
   ENVIRONMENT_IS_WORKER = !worker_threads.isMainThread;
 #if PTHREADS
@@ -196,8 +196,8 @@ if (ENVIRONMENT_IS_NODE) {
 
   // These modules will usually be used on Node.js. Load them eagerly to avoid
   // the complexity of lazy-loading.
-  var fs = require('fs');
-  var nodePath = require('path');
+  var fs = require('node:fs');
+  var nodePath = require('node:path');
 
 #if EXPORT_ES6
   // EXPORT_ES6 + ENVIRONMENT_IS_NODE always requires use of import.meta.url,

src/shell_minimal.js

@@ -94,7 +94,7 @@ if (ENVIRONMENT_IS_NODE && ENVIRONMENT_IS_SHELL) {
 var defaultPrint = console.log.bind(console);
 var defaultPrintErr = console.error.bind(console);
 if (ENVIRONMENT_IS_NODE) {
-  var fs = require('fs');
+  var fs = require('node:fs');
   defaultPrint = (...args) => fs.writeSync(1, args.join(' ') + '\n');
   defaultPrintErr = (...args) => fs.writeSync(2, args.join(' ') + '\n');
 }
@@ -167,7 +167,7 @@ if (!ENVIRONMENT_IS_PTHREAD) {
 // Wasm or Wasm2JS loading:
 
 if (ENVIRONMENT_IS_NODE) {
-  var fs = require('fs');
+  var fs = require('node:fs');
 #if WASM == 2
   if (typeof WebAssembly != 'undefined') Module['wasm'] = fs.readFileSync(__dirname + '/{{{ TARGET_BASENAME }}}.wasm');
   else eval(fs.readFileSync(__dirname + '/{{{ TARGET_BASENAME }}}.wasm.js')+'');