squash nasty backend error for broken code

[gavinking]

Given this broken code:

interface Baz {}
interface Bar {}

interface Producer<out T> {
    shared formal void consume(T t);
}

interface ProducerBaz satisfies Producer<Baz> {}

interface ProducerBar satisfies Producer<Bar> {}

class Prod() satisfies Producer<Baz&Bar> & ProducerBaz & ProducerBar {
    shared actual void consume(Baz&Bar t) {}
}

I don't even notice the typechecker error, because my whole editor fills up with this backend error:

Ceylon backend error: method does not override or implement a method from a supertype

The error does have some location information (line 13) but for some reason it doesn't have what the IDE needs to localize the error.

[gavinking]

The error does have some location information (line 13) but for some reason it doesn't have what the IDE needs to localize the error.

@davidfestal is that a (new) bug in the IDE?

[jvasileff]

I don't even notice the typechecker error

I'm going to lobby again for backend errors to be suppressed in the IDE and CLI when typechecker errors exist, as a fix for cases like this and https://github.com/ceylon/ceylon/issues/6164.

I've never filed a bug report for a backend error caused by an attempt to compile invalid code, but I see this every day (ok, I shouldn't admit to writing that much bad code). Squashing most of these seems like a huge task, and all of them, impossible.

[jvasileff]

but I see this every day

For example:

[gavinking]

@jvasileff Yeah, OK, so I've changed it to hide backend errors in any source file which doesn't pass the typechecker. I think that's a pretty big improvement.