refactor: Move to anstream + anstyle for styling

[Muscraft]

rustc uses termcolor for styling and writing, while annotate-snippets uses anstyle for styling and currently writes directly to a String. When rendering directly to a terminal, there isn't/shouldn't be any differences. Still, there are differences in the escape sequences, which leads to slightly different output in JSON and SVG tests. As part of my work to have rustc use annotate-snippets, and to reduce the test differences between the two, I switched rustc to use anstlye and anstream for styling and writing.

The first commit migrates to anstyle and anstream and notably does not change the output. This is because it includes extra formatting to ensure that anstyle + anstream match the current output exactly. Most of this code is unnecessary, as it adds redundant resets or uses 256-color (8-bit) when it could be using 4-bit color. The subsequent commits remove this extra formatting while maintaining the correct output when rendered.

Zulip discussion

[rustbot]

The list of allowed third-party dependencies may have been modified! You must ensure that any new dependencies have compatible licenses before merging.

cc @davidtwco, @wesleywiser

These commits modify the Cargo.lock file. Unintentional changes to Cargo.lock can be introduced when switching branches and rebasing PRs.

If this was unintentional then you should revert the changes before this PR is merged.
Otherwise, you can ignore this comment.

[rustbot]

r? @lcnr

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[Urgau]

I'm curious about the perf impact, let's see if there are any.

@bors try @rust-timer queue

[lcnr]

r? compiler

[rust-bors]

☀️ Try build successful (CI)
Build commit: 57098c1 (57098c130d013c0fdc87707aa7098579281756c6, parent: 1e1a39441bd11aba541a48ba714d939490fc7b85)

[rust-timer]

Finished benchmarking commit (57098c1): comparison URL.

Overall result: ❌✅ regressions and improvements - no action needed

Benchmarking this pull request means it may be perf-sensitive – we'll automatically label it not fit for rolling up. You can override this, but we strongly advise not to, due to possible changes in compiler perf.

@bors rollup=never
@rustbot label: -S-waiting-on-perf -perf-regression

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	0.1%	[0.1%, 0.1%]	1
Improvements ✅ (primary)	-1.0%	[-1.0%, -1.0%]	1
Improvements ✅ (secondary)	-0.3%	[-0.3%, -0.3%]	1
All ❌✅ (primary)	-1.0%	[-1.0%, -1.0%]	1

Max RSS (memory usage)

Results (primary -1.0%, secondary 1.8%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	1.8%	[1.8%, 1.8%]	1
Improvements ✅ (primary)	-1.0%	[-1.0%, -1.0%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-1.0%	[-1.0%, -1.0%]	1

Cycles

This benchmark run did not return any relevant results for this metric.

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 471.179s -> 472.5s (0.28%)
Artifact size: 387.76 MiB -> 387.69 MiB (-0.02%)

[rustbot]

This PR was rebased onto a different master commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

[davidtwco]

@bors r+

[bors]

📌 Commit 5aedef1 has been approved by davidtwco

It is now in the queue for this repository.

[bors]

⌛ Testing commit 5aedef1 with merge dc1feab...

[bors]

☀️ Test successful - checks-actions
Approved by: davidtwco
Pushing dc1feab to master...

[github-actions]

What is this?

This is an experimental post-merge analysis report that shows differences in test outcomes between the merged PR and its parent PR.

Comparing 4d94478 (parent) -> dc1feab (this PR)

Test differences

Show 10 test diffs

10 doctest diffs were found. These are ignored, as they are noisy.

Test dashboard

Run

cargo run --manifest-path src/ci/citool/Cargo.toml -- \
    test-dashboard dc1feabef242259d61bd930713de3250577c1c71 --output-dir test-dashboard

And then open test-dashboard/index.html in your browser to see an overview of all executed tests.

Job duration changes

1. dist-aarch64-linux: 6547.4s -> 9042.4s (38.1%)
2. dist-apple-various: 3723.7s -> 4612.3s (23.9%)
3. aarch64-apple: 8377.2s -> 10028.1s (19.7%)
4. x86_64-rust-for-linux: 2725.9s -> 3003.4s (10.2%)
5. aarch64-gnu-llvm-20-1: 3575.8s -> 3939.1s (10.2%)
6. pr-check-1: 1968.4s -> 1772.4s (-10.0%)
7. i686-gnu-1: 7563.6s -> 8156.7s (7.8%)
8. x86_64-gnu-llvm-20: 2501.8s -> 2692.3s (7.6%)
9. aarch64-gnu-llvm-20-2: 2239.2s -> 2407.1s (7.5%)
10. dist-aarch64-apple: 7138.8s -> 6655.2s (-6.8%)

How to interpret the job duration changes?

Job durations can vary a lot, based on the actual runner instance
that executed the job, system noise, invalidated caches, etc. The table above is provided
mostly for t-infra members, for simpler debugging of potential CI slow-downs.

[rust-timer]

Finished benchmarking commit (dc1feab): comparison URL.

Overall result: ✅ improvements - no action needed

@rustbot label: -perf-regression

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-0.1%	[-0.2%, -0.1%]	11
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-0.1%	[-0.2%, -0.1%]	11

Max RSS (memory usage)

Results (secondary -0.8%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.8%	[-0.8%, -0.8%]	1
All ❌✅ (primary)	-	-	0

Cycles

This benchmark run did not return any relevant results for this metric.

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 473.902s -> 472.366s (-0.32%)
Artifact size: 390.68 MiB -> 390.71 MiB (0.01%)