native implementation mistaken for header

[jvasileff]

This type checks:

class NC2() {
    native("jvm") shared void foo() => print("impl 1");
    native("jvm") shared void foo() => print("impl 2");
}

but, should have:

1. "Native member does not implement any header member: foo in NC2"
2. "Duplicate native implementation: foo"

[quintesse]

Can't reproduce this, I get:

./source/test/test.ceylon:8: error: foo() is already defined in NC2
    native("jvm") shared void foo() => print("impl 2");

[jvasileff]

Oh, right, this is actually much more nuanced.

1. In Eclipse, with just "compile to project to JS", no error is produced for the original example.
2. Same as above, but with one of the declarations removed, an error is produced.
3. At the CLI, ceylon compile-js produces no error regardless of how many native("jvm") declarations exist.
4. If instead, we use native("js"), ceylon compile produces an error for one declaration, not with two or more.

[quintesse]

1. and 3. are basically the same thing and is something specific for the JS backend: it just ignores all errors in code marked for the JVM. The other two are also a single issue really, which is that no dups are detected if there's no header.

[quintesse]

The duplicates should now generate proper errors.

[quintesse]

Will close this issue because what's described has been fixed.