Ensure EXPORT_ES6 is tested on Node.js

Author: kleisauke

src/preamble.js

@@ -649,7 +649,8 @@ if (Module['locateFile']) {
 #if EXPORT_ES6 && USE_ES6_IMPORT_META && !SINGLE_FILE // in single-file mode, repeating WASM_BINARY_FILE would emit the contents again
 } else {
   // Use bundler-friendly `new URL(..., import.meta.url)` pattern; works in browsers too.
-  wasmBinaryFile = new URL('{{{ WASM_BINARY_FILE }}}', import.meta.url).toString();
+  // FIXME: On Node.js this needs to be wrapped in fileURLToPath.
+  wasmBinaryFile = new URL('{{{ WASM_BINARY_FILE }}}', import.meta.url).href;
 }
 #endif
 

test/test_other.py

@@ -234,12 +234,24 @@ def test_emcc_generate_config(self):
         os.remove(config_path)
 
   def test_emcc_output_mjs(self):
-    self.run_process([EMCC, '-o', 'hello_world.mjs', test_file('hello_world.c')])
+    # FIXME: https://github.com/emscripten-core/emscripten/issues/11792
+    create_file('extern-pre.js', '''
+      import { dirname } from "path";
+      import { fileURLToPath } from "url";
+      import { createRequire } from "module";
+      const require = createRequire(import.meta.url);
+      const __dirname = dirname(fileURLToPath(import.meta.url));
+    ''')
+    # FIXME: locateFile hook should not be necessary
+    create_file('extern-post.js', '''
+      await Module({ locateFile: (fileName, scriptDirectory) => scriptDirectory + fileName });
+    ''')
+    self.run_process([EMCC, '-o', 'hello_world.mjs', test_file('hello_world.c'),
+                      '--extern-pre-js', 'extern-pre.js',
+                      '--extern-post-js', 'extern-post.js'])
     output = read_file('hello_world.mjs')
     self.assertContained('export default Module;', output)
-    # TODO(sbc): Test that this is actually runnable.  We currently don't have
-    # any tests for EXPORT_ES6 but once we do this should be enabled.
-    # self.assertContained('hello, world!', self.run_js('hello_world.mjs'))
+    self.assertContained('hello, world!', self.run_js('hello_world.mjs'))
 
   @parameterized({
     '': (True, [],),