Configure snippets renderer to match rustc/Cargo style

[kornelski]

Renderer::styled() defaults to green labels for note and help, but Cargo and rustc use cyan.

[rustbot]

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[epage]

this should be a pr to annotate snippets if there is a discrepancy

[kornelski]

I don't understand.

shell.render_message(Level::Note.title("foo")) uses a wrong color. The snippets don't specify a color themselves by design, the color is imposed on the snippets by the stylesheet initialized by styled().

[kornelski]

Oh, I see. I thought the CI test failure was a false positive:

     Summary semver requires new major version: 1 major and 0 minor checks failed
--- failure constructible_struct_adds_field: externally-constructible struct adds field ---

Description:
A pub struct constructible with a struct literal has a new pub field. Existing struct literals must be updated to include the new field.
        ref: https://doc.rust-lang.org/reference/expressions/struct-expr.html
       impl: https://github.com/obi1kenobi/cargo-semver-checks/tree/v0.41.0/src/lints/constructible_struct_adds_field.ron

but there's also a UI test failing.

[epage]

The expectation is that annotate-snippets defaults are rustc's defaults. If annotate-snippets is not matching rustc, then that is a bug with annotate-snippers that should be resolved. We should not work around that bug in Cargo.

[epage]

Also, i would recommend being pretty sure about a resolution when marking things resolved, otherwise leave it to the original person. While this is a smaller PR and so its less likely to be lost, in larger PRs that can easily make it so misunderstood feedback gets lost.