Feedback on emscripten-core#21775

- Add changelog entry
- Fix typo in error message
- Improve error message

ChangeLog.md

@@ -20,6 +20,10 @@ See docs/process.md for more on how version tagging works.
 
 3.1.58 (in development)
 -----------------------
+- In `-sMODULARIZE` mode, the argument passed into the module constructor is
+  no longer mutated in place.  The expectation is that the module instance will
+  be available via the constructor return value.  Attempting to access methods
+  on the object passed *into* the constructor will now abort. (#21775)
 - Enable use of `::` to escape port option separator (#21710)
 - In multi-threaded builds `--extern-pre-js` and `--extern-post-js` code is
   now only run on the main thread, and not on each of the workers. (#21750)

src/postamble_modularize.js

@@ -29,11 +29,7 @@ for (const prop of Object.keys(Module)) {
     Object.defineProperty(moduleArg, prop, {
       configurable: true,
       get() {
-#if WASM_ASYNC_COMPILATION
-        abort(`Access to module property ('${prop}') is no longer possible via the incoming module contructor argument; Instead, use the result of the module promise.`)
-#else
-        abort(`Access to module property ('${prop}') is no longer possible via the module input argument; Instead, use the module constructor return value.`)
-#endif
+        abort(`Access to module property ('${prop}') is no longer possible via the module constructor argument; Instead, use the result of the module constructor.`)
       }
     });
   }

test/test_other.py

@@ -6446,7 +6446,7 @@ def test_modularize_argument_misuse(self):
       var promise = Module(arg);
       arg._foo();''')
 
-    expected = "Aborted(Access to module property ('_foo') is no longer possible via the incoming module contructor argument; Instead, use the result of the module promise"
+    expected = "Aborted(Access to module property ('_foo') is no longer possible via the module constructor argument; Instead, use the result of the module constructor"
     self.do_runf('test.c', expected, assert_returncode=NON_ZERO, emcc_args=['--no-entry', '-sMODULARIZE', '--extern-post-js=post.js'])
 
   def test_export_all_3142(self):
@@ -6983,7 +6983,7 @@ def test_dlopen_bad_flags(self):
     out = self.run_js('a.out.js')
     self.assertContained('invalid mode for dlopen(): Either RTLD_LAZY or RTLD_NOW is required', out)
 
-  def test_dlopen_contructors(self):
+  def test_dlopen_constructors(self):
     create_file('side.c', r'''
       #include <stdio.h>
       #include <assert.h>
@@ -6998,7 +6998,7 @@ def test_dlopen_contructors(self):
       __attribute__((constructor)) void ctor(void) {
         printf("foo address: %p\n", ptr);
         // Check that relocations have already been applied by the time
-        // contructor functions run.
+        // constructor functions run.
         check_relocations();
         printf("done ctor\n");
       }