Make -Ztrack-diagnostics emit like a note

[Muscraft]

#t-compiler/diagnostics > Rendering -Ztrack-diagnostics like a note

As discussed on the Zulip thread above, I want to make -Ztrack-diagnostics emit like a note. This is because I find its current output jarring, and the fact that it gets rendered completely left-aligned, even in the middle of a snippet, seems like something that should be changed. Turning it into a note seems like the best choice, as it would align it with the rest of the output, and note is already used for somewhat similar things, like seeing why a lint was fired.

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Note: turning -Ztrack-diagnostics into a note will also make annotate-snippets API a bit cleaner

[rustbot]

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[petrochenkov]

It's now emitted as a note into the json output as well, right?

Could you then migrate tests using -Ztrack-diagnostics from //@ error-pattern: created at to //~ NOTE created at?
All of them are either in tests\ui\track-diagnostics or in tests\rustdoc-ui\track-diagnostics.rs.

//@ dont-require-annotations: NOTE can be used to keep the NOTE annotations non-viral, if necessary.

[Muscraft]

It's now emitted as a note into the json output as well, right?

No, I only made it so that it gets rendered like a note in HumanEmitter

Could you then migrate tests using -Ztrack-diagnostics from //@ error-pattern: created at to //~ NOTE created at?
All of them are either in tests\ui\track-diagnostics or in tests\rustdoc-ui\track-diagnostics.rs.

//@ dont-require-annotations: NOTE can be used to keep the NOTE annotations non-viral, if necessary.

Since this isn't changing the json, would you still like me to do this?

[petrochenkov]

Since this isn't changing the json, would you still like me to do this?

Compiletest is working on the json output, so //~ NOTE won't work if the output is not there.
Ideally this would be actually outputted in some structured form, and not just into the rendered text.

[rustbot]

Some changes occurred in src/tools/clippy

cc @rust-lang/clippy

[Muscraft]

Ideally this would be actually outputted in some structured form, and not just into the rendered text.

I don't know how I would add it to the JSON output, but if I need to, I'll see what I can figure out.