Avoid unnecessary use of array.forEach in JS. NFC (emscripten-core#24895)

In both these cases the code is smaller and simpler.

Author: sbc100

src/lib/libfs_shared.js

@@ -19,15 +19,13 @@ addToLibrary({
     if (typeof Browser != 'undefined') Browser.init();
 #endif
 
-    var handled = false;
-    preloadPlugins.forEach((plugin) => {
-      if (handled) return;
+    for (var plugin of preloadPlugins) {
       if (plugin['canHandle'](fullname)) {
         plugin['handle'](byteArray, fullname, finish, onerror);
-        handled = true;
+        return true;
       }
-    });
-    return handled;
+    }
+    return false;
   },
 
   // Preloads a file asynchronously. You can call this before run, for example in

src/lib/liblz4.js

@@ -30,7 +30,7 @@ addToLibrary({
                                                                       compressedData['cachedOffset'] + (i+1)*LZ4.CHUNK_SIZE);
         assert(compressedData['cachedChunks'][i].length === LZ4.CHUNK_SIZE);
       }
-      pack['metadata'].files.forEach((file) => {
+      for (var file of pack['metadata'].files) {
         var dir = PATH.dirname(file.filename);
         var name = PATH.basename(file.filename);
         FS.createPath('', dir, true, true);
@@ -40,29 +40,27 @@ addToLibrary({
           start: file.start,
           end: file.end,
         });
-      });
+      }
       // Preload files if necessary. This code is largely similar to
       // createPreloadedFile in library_fs.js. However, a main difference here
       // is that we only decompress the file if it can be preloaded.
       // Abstracting out the common parts seems to be more effort than it is
       // worth.
       if (preloadPlugin) {
         Browser.init();
-        pack['metadata'].files.forEach((file) => {
-          var handled = false;
+        for (var file of pack['metadata'].files) {
           var fullname = file.filename;
-          preloadPlugins.forEach((plugin) => {
-            if (handled) return;
+          for (var plugin of preloadPlugins) {
             if (plugin['canHandle'](fullname)) {
               var dep = getUniqueRunDependency('fp ' + fullname);
               addRunDependency(dep);
               var finish = () => removeRunDependency(dep);
               var byteArray = FS.readFile(fullname);
               plugin['handle'](byteArray, fullname, finish, finish);
-              handled = true;
+              break;
             }
-          });
-        });
+          }
+        }
       }
     },
     createNode(parent, name, mode, dev, contents, mtime) {

test/code_size/test_codesize_hello_dylink_all.json

@@ -1,7 +1,7 @@
 {
-  "a.out.js": 246847,
+  "a.out.js": 246838,
   "a.out.nodebug.wasm": 597826,
-  "total": 844673,
+  "total": 844664,
   "sent": [
     "IMG_Init",
     "IMG_Load",

test/test_other.py

@@ -15594,10 +15594,11 @@ def test_add_js_function_bigint(self, memory64, wasm_function):
 
   @parameterized({
     '': ([],),
+    'lz4': (['-sLZ4'],),
     'pthread': (['-g', '-pthread', '-Wno-experimental', '-sPROXY_TO_PTHREAD', '-sEXIT_RUNTIME'],),
   })
   def test_preload_module(self, args):
-    if args:
+    if '-pthread' in args:
       self.setup_node_pthreads()
     # TODO(sbc): This test is copyied from test_browser.py.  Perhaps find a better way to
     # share code between them.
@@ -15647,7 +15648,7 @@ def test_preload_module(self, args):
       }
     ''')
     expected = 'done\n'
-    if args:
+    if '-pthread' in args:
       expected = "sharedModules: { '/library.so': Module [WebAssembly.Module] {} }\ndone\n"
     self.do_runf('main.c', expected, cflags=['-sMAIN_MODULE=2', '--preload-file', '[email protected]', '--use-preload-plugins'] + args)