commit 8521d4f5d908aeacb426b698003773f8a99b3fdc
author Jens Johansen <jensj@google.com> Mon Jan 27 01:27:50 2025 -0800
committer Commit Queue <dart-scoped@luci-project-accounts.iam.gserviceaccount.com> Mon Jan 27 01:27:50 2025 -0800
tree de3cd852a8a4b4af0bd8e8084db446a8462c4e7e
parent 2d83ca1d387fc0c3730a068549dbc63bdeea53c7

[CFE] Fix coverage destroyed by (wrong) offsets on extension method tearoffs

Say you have a class method like this:

```
class Bar {
  /*offset a*/ void /*offset b*/ qux() {
    /*offset c*/ print("hello");
  }
}
```

Lets also say that this method is run.
This will mark offset a and offset c as hits.
Offset b does not exist in coverage terms.

Now say you have an extension mehod like this:

```
extension Foo on Bar {
  /*offset a*/ void /*offset b*/ baz() {
    /*offset c*/ print("hello");
  }
}
```

Lets also say that this method is also executed.
This will mark offset a and offset c as hits.
Offset b does not exist in coverage terms for this method.

Because extension methods are special though we create a special tearoff for
it. Lets say we didn't execute that one.
The tearoff method - before this CL - had offset b on positions that caused
the position to exist in coverage terms, and as the method wasn't executed
this would make it a miss.

This CL fixes the issue by setting the offsets on the tearoff that before
introduced offset b to offset a instead.

Change-Id: I3a5339135f3d76327624b35f04cc14afccaf487a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/404563
Commit-Queue: Jens Johansen <jensj@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
Reviewed-by: Johnni Winther <johnniwinther@google.com>