Switch binaryen.js/wasm to ESM

CHANGELOG.md

@@ -15,6 +15,13 @@ full changeset diff at the end of each section.
 Current Trunk
 -------------
 
+- JS and Wasm builds now emit ECMAScript modules. New usage is:
+  ```js
+  import Binaryen from "path/to/binaryen.js";
+  const binaryen = await Binaryen();
+  ...
+  ```
+
 v102
 ----
 

CMakeLists.txt

@@ -362,10 +362,10 @@ if(EMSCRIPTEN)
   target_link_libraries(binaryen_wasm wasm asmjs emscripten-optimizer passes ir cfg support wasm)
   target_link_libraries(binaryen_wasm "-s NO_FILESYSTEM=0")
   target_link_libraries(binaryen_wasm "-s NODERAWFS=0")
-  target_link_libraries(binaryen_wasm "-s EXPORT_NAME=binaryen")
+  target_link_libraries(binaryen_wasm "-s EXPORT_NAME=Binaryen")
+  target_link_libraries(binaryen_wasm "-s EXPORT_ES6=1")
   target_link_libraries(binaryen_wasm "--post-js ${CMAKE_CURRENT_SOURCE_DIR}/src/js/binaryen.js-post.js")
   target_link_libraries(binaryen_wasm "--extern-pre-js ${CMAKE_CURRENT_SOURCE_DIR}/src/js/binaryen.js-extern-pre.js")
-  target_link_libraries(binaryen_wasm "--extern-post-js ${CMAKE_CURRENT_SOURCE_DIR}/src/js/binaryen.js-extern-post.js")
   target_link_libraries(binaryen_wasm optimized "--closure 1")
   target_link_libraries(binaryen_wasm optimized "--closure-args \"--language_in=ECMASCRIPT6 --language_out=ECMASCRIPT6\"")
   target_link_libraries(binaryen_wasm optimized "-flto")
@@ -386,10 +386,10 @@ if(EMSCRIPTEN)
   endif()
   target_link_libraries(binaryen_js "-s NO_FILESYSTEM=0")
   target_link_libraries(binaryen_js "-s NODERAWFS=0")
-  target_link_libraries(binaryen_js "-s EXPORT_NAME=binaryen")
+  target_link_libraries(binaryen_js "-s EXPORT_NAME=Binaryen")
+  target_link_libraries(binaryen_js "-s EXPORT_ES6=1")
   target_link_libraries(binaryen_js "--post-js ${CMAKE_CURRENT_SOURCE_DIR}/src/js/binaryen.js-post.js")
   target_link_libraries(binaryen_js "--extern-pre-js ${CMAKE_CURRENT_SOURCE_DIR}/src/js/binaryen.js-extern-pre.js")
-  target_link_libraries(binaryen_js "--extern-post-js ${CMAKE_CURRENT_SOURCE_DIR}/src/js/binaryen.js-extern-post.js")
   target_link_libraries(binaryen_js optimized "--closure 1")
   target_link_libraries(binaryen_js optimized "--closure-args \"--language_in=ECMASCRIPT6 --language_out=ECMASCRIPT6\"")
   target_link_libraries(binaryen_js optimized "-flto")

scripts/test/binaryenjs.py

@@ -33,7 +33,7 @@ def do_test_binaryen_js_with(which):
         if not s.endswith('.js'):
             continue
         print(s)
-        f = open('a.js', 'w')
+        f = open('a.mjs', 'w')
         # avoid stdout/stderr ordering issues in some js shells - use just stdout
         f.write('''
             console.warn = console.error = console.log;
@@ -45,8 +45,7 @@ def do_test_binaryen_js_with(which):
         f.write(support.js_test_wrap().replace('%TEST%', test_src))
         f.close()
 
-        def test(engine):
-            cmd = [engine, 'a.js']
+        def test(cmd):
             if 'fatal' not in s:
                 out = support.run_command(cmd, stderr=subprocess.STDOUT)
             else:
@@ -58,10 +57,10 @@ def test(engine):
 
         # run in all possible shells
         if shared.MOZJS:
-            test(shared.MOZJS)
+            test([shared.MOZJS, '-m', 'a.mjs'])
         if shared.NODEJS:
             if node_has_wasm or 'WebAssembly.' not in test_src:
-                test(shared.NODEJS)
+                test([shared.NODEJS, 'a.mjs'])
             else:
                 print('Skipping ' + test_path + ' because WebAssembly might not be supported')
 
@@ -80,20 +79,30 @@ def update_binaryen_js_tests():
     for s in shared.get_tests(shared.get_test_dir('binaryen.js'), ['.js']):
         basename = os.path.basename(s)
         print(basename)
-        f = open('a.js', 'w')
+        f = open('a.mjs', 'w')
+        # avoid stdout/stderr ordering issues in some js shells - use just stdout
+        f.write('''
+            console.warn = console.error = console.log;
+        ''')
         f.write(open(shared.BINARYEN_JS).read())
         test_src = open(s).read()
         f.write(support.js_test_wrap().replace('%TEST%', test_src))
         f.close()
-        if shared.MOZJS or node_has_wasm or 'WebAssembly.' not in test_src:
-            cmd = [shared.MOZJS or shared.NODEJS, 'a.js']
+
+        def update(cmd):
             if 'fatal' not in basename:
                 out = support.run_command(cmd, stderr=subprocess.STDOUT)
             else:
                 # expect an error - the specific error code will depend on the vm
                 out = support.run_command(cmd, stderr=subprocess.STDOUT, expected_status=None)
             with open(s + '.txt', 'w') as o:
                 o.write(out)
+
+        # run in available shell
+        if shared.MOZJS:
+            update([shared.MOZJS, '-m', 'a.mjs'])
+        elif node_has_wasm or 'WebAssembly.' not in test_src:
+            update([shared.NODEJS, 'a.mjs'])
         else:
             print('Skipping ' + basename + ' because WebAssembly might not be supported')
 

scripts/test/support.py

@@ -199,8 +199,9 @@ def js_test_wrap():
     # common wrapper code for JS tests, waiting for binaryen.js to become ready
     # and providing common utility used by all tests:
     return '''
-        binaryen.ready.then(function() {
+        (async function __in_test_code__() {
+            var binaryen = await Binaryen()
             function assert(x) { if (!x) throw Error('Test assertion failed'); }
             %TEST%
-        });
+        })();
     '''

src/js/binaryen.js-extern-pre.js

@@ -1,2 +1,4 @@
-var binaryen = {};
-(function() {
+// FIXME: The Emscripten shell requires this variable to be present, even though
+// we are building to ES6 (where it doesn't exist) and the .wasm blob is inlined
+// see: https://github.com/emscripten-core/emscripten/issues/11792
+var __dirname = "";

src/js/binaryen.js-post.js

@@ -4807,46 +4807,12 @@ Module['exit'] = function(status) {
   if (status != 0) throw new Error('exiting due to error: ' + status);
 };
 
-// Indicates if Binaryen has been loaded and is ready
-Module['isReady'] = runtimeInitialized;
-
-// Provide a mechanism to tell when the module is ready
-//
-// if (!binaryen.isReady) await binaryen.ready;
-// ...
-//
-let pendingPromises = [];
-let initializeError = null;
-
-Object.defineProperty(Module, 'ready', {
-  get() {
-    return new Promise((resolve, reject) => {
-      if (initializeError) {
-        reject(initializeError);
-      } else if (runtimeInitialized) {
-        resolve(Module);
-      } else {
-        pendingPromises.push({ resolve, reject });
-      }
-    });
-  }
-});
-
 // Intercept the onRuntimeInitialized hook if necessary
 if (runtimeInitialized) {
   initializeConstants();
 } else {
   Module['onRuntimeInitialized'] = (super_ => () => {
-    try {
-      initializeConstants();
-      if (super_) super_();
-      Module['isReady'] = true;
-      pendingPromises.forEach(p => { p.resolve(Module) });
-    } catch (e) {
-      initializeError = e;
-      pendingPromises.forEach(p => { p.reject(e) });
-    } finally {
-      pendingPromises = [];
-    }
+    initializeConstants();
+    if (super_) super_();
   })(Module['onRuntimeInitialized']);
 }

test/binaryen.js/kitchen-sink.js

@@ -839,7 +839,7 @@ function test_relooper() {
     var block0 = relooper.addBlock(makeCallCheck(0));
     var block1 = relooper.addBlock(makeCallCheck(1));
     var block2 = relooper.addBlock(makeCallCheck(2));
-    temp = makeDroppedInt32(10);
+    var temp = makeDroppedInt32(10);
     relooper.addBranch(block0, block1, makeInt32(55), temp);
     relooper.addBranch(block0, block2, null, makeDroppedInt32(20));
     var body = relooper.renderAndDispose(block0, 0, module);
@@ -1006,7 +1006,7 @@ function test_interpret() {
   module = new binaryen.Module();
 
   module.addFunctionImport("print-i32", "spectest", "print", binaryen.i32, binaryen.none);
-  call = module.call("print-i32", [ makeInt32(1234) ], binaryen.None);
+  var call = module.call("print-i32", [ makeInt32(1234) ], binaryen.None);
   var starter = module.addFunction("starter", binaryen.none, binaryen.none, [], call);
   module.setStart(starter);