Convert asyncLoad from callbacks to promise. NFC (#23065)

This is an internal function that should not have any external users.

Author: sbc100

src/library.js

@@ -2182,25 +2182,19 @@ addToLibrary({
   },
 
   $asyncLoad__docs: '/** @param {boolean=} noRunDep */',
-  $asyncLoad: (url, onload, onerror, noRunDep) => {
-    var dep = !noRunDep ? getUniqueRunDependency(`al ${url}`) : '';
-    readAsync(url).then(
-      (arrayBuffer) => {
-#if ASSERTIONS
-        assert(arrayBuffer, `Loading data file "${url}" failed (no arrayBuffer).`);
-#endif
-        onload(new Uint8Array(arrayBuffer));
-        if (dep) removeRunDependency(dep);
-      },
-      (err) => {
-        if (onerror) {
-          onerror();
-        } else {
-          throw `Loading data file "${url}" failed.`;
-        }
-      }
-    );
-    if (dep) addRunDependency(dep);
+  $asyncLoad: (url, noRunDep) => {
+    return new Promise((resolve, reject) => {
+      var dep = !noRunDep ? getUniqueRunDependency(`al ${url}`) : '';
+      if (dep) addRunDependency(dep);
+      readAsync(url).then(
+        (arrayBuffer) => {
+  #if ASSERTIONS
+          assert(arrayBuffer, `Loading data file "${url}" failed (no arrayBuffer).`);
+  #endif
+          resolve(new Uint8Array(arrayBuffer));
+          if (dep) removeRunDependency(dep);
+        }, reject);
+    });
   },
 
   $alignMemory: (size, alignment) => {

src/library_async.js

@@ -470,7 +470,8 @@ addToLibrary({
   emscripten_wget_data__async: true,
   emscripten_wget_data: (url, pbuffer, pnum, perror) => {
     return Asyncify.handleSleep((wakeUp) => {
-      asyncLoad(UTF8ToString(url), (byteArray) => {
+      /* no need for run dependency, this is async but will not do any prepare etc. step */
+      asyncLoad(UTF8ToString(url), /*noRunDep=*/true).then((byteArray) => {
         // can only allocate the buffer after the wakeUp, not during an asyncing
         var buffer = _malloc(byteArray.length); // must be freed by caller!
         HEAPU8.set(byteArray, buffer);
@@ -481,7 +482,7 @@ addToLibrary({
       }, () => {
         {{{ makeSetValue('perror',  0, '1', 'i32') }}};
         wakeUp();
-      }, true /* no need for run dependency, this is async but will not do any prepare etc. step */ );
+      });
     });
   },
 

src/library_dylink.js

@@ -1024,7 +1024,7 @@ var LibraryDylink = {
 
       var libFile = locateFile(libName);
       if (flags.loadAsync) {
-        return new Promise((resolve, reject) => asyncLoad(libFile, resolve, reject));
+        return asyncLoad(libFile);
       }
 
       // load the binary synchronously

src/library_fs_shared.js

@@ -76,7 +76,7 @@ addToLibrary({
     }
     addRunDependency(dep);
     if (typeof url == 'string') {
-      asyncLoad(url, processData, onerror);
+      asyncLoad(url).then(processData, onerror);
     } else {
       processData(url);
     }

src/library_wget.js

@@ -64,7 +64,8 @@ var LibraryWget = {
   emscripten_async_wget_data__proxy: 'sync',
   emscripten_async_wget_data: (url, userdata, onload, onerror) => {
     {{{ runtimeKeepalivePush() }}}
-    asyncLoad(UTF8ToString(url), (byteArray) => {
+    /* no need for run dependency, this is async but will not do any prepare etc. step */
+    asyncLoad(UTF8ToString(url), /*noRunDep=*/true).then((byteArray) => {
       {{{ runtimeKeepalivePop() }}}
       callUserCallback(() => {
         var buffer = _malloc(byteArray.length);
@@ -79,7 +80,7 @@ var LibraryWget = {
           {{{ makeDynCall('vp', 'onerror') }}}(userdata);
         });
       }
-    }, true /* no need for run dependency, this is async but will not do any prepare etc. step */ );
+    });
   },
 
   emscripten_async_wget2__deps: ['$PATH_FS', '$wget', '$stackRestore', '$stringToUTF8OnStack'],

test/other/codesize/test_codesize_hello_dylink.gzsize

@@ -1 +1 @@
-6339
+6298

test/other/codesize/test_codesize_hello_dylink.jssize

@@ -1 +1 @@
-13936
+13867