Extend macro name suggestion span

[etaoins]

When we suggest the replacement for a macro we include the "!" in the suggested replacement but the span only contains the name of the macro itself. Using that replacement would cause a duplicate "!" in the resulting code.

Fix by extending the suggestion's span by one byte to include the "!". The error span itself still only includes the macro's name.

Fixes #47418

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[zackmdavis]

It's legal (despite being extremely irregular style) for there to be space between the macro name and the exclamation point, so we can't simply add a byte to the span.

fn main() {
    println 
                 !("rah"); // successfully prints "rah"
}

[etaoins]

@zackmdavis Ouch, good catch! I'll need to rethink this.

[estebank]

Thank you for taking the time to fix this!

What about just changing the suggestion to not include !? That way you don't have to worry about @zackmdavis' valid point.

[etaoins]

@estebank

I have a branch for that on my home machine. I think the current message with the ! is a bit nicer but we don't have access to the original span including the ! at this point. If we're okay losing the ! in then I'll open a PR with my branch once I'm back home and add you as a reviewer.

Thanks for the feedback!

[estebank]

If we're okay losing the ! in then I'll open a PR with my branch once I'm back home and add you as a reviewer.

It should be fine, @etaoins. Tools don't care and will do the right thing, and for people it should be apparent enough that the span doesn't include the !. If the updated stderr files look too confusing with the change, what we could do is expand the suggestion's message so that it is shown on it's own:

error: cannot find macro `printlx!` in this scope
  --> $DIR/macro-name-typo.rs:12:5
   |
12 |     printlx!("oh noes!"); //~ ERROR cannot find
   |     ^^^^^^^ help: you could try the macro: `println!`
   = help: although `printlx` wasn't found, there's a macro named `println`:
   |
12 |     println!("oh noes!"); //~ ERROR cannot find
   |     ^^^^^^^