Use yarn instead of npm for JS/TS dependencies

[yotamofek]

Building on @lolbinarycat 's excellent work ( #148672 ).

npm apparently has certain edge-cases where it doesn't actually respect the lockfile it's fed, which has led to at least one CI breakage.

yarn seems to not suffer from those same issues, and also has a --frozen flag for its install command

[rustbot]

This PR modifies src/bootstrap/src/core/config.

If appropriate, please update CONFIG_CHANGE_HISTORY in src/bootstrap/src/utils/change_tracker.rs.

This PR modifies bootstrap.example.toml.

If appropriate, please update CONFIG_CHANGE_HISTORY in src/bootstrap/src/utils/change_tracker.rs.

Some changes occurred in HTML/CSS/JS.

cc @GuillaumeGomez, @jsha, @lolbinarycat

[rustbot]

r? @clubby789

rustbot has assigned @clubby789.
They will have a look at your PR within the next two weeks and either review your PR or reassign to another reviewer.

Use r? to explicitly pick a reviewer

[yotamofek]

r? @Kobzol since you're already kinda familiar with the situation?

(maybe also @notriddle for the small TS fixes, if you can take a look)

[rustbot]

tidy extra checks were modified.

cc @lolbinarycat

[bors]

☔ The latest upstream changes (presumably #148885) made this pull request unmergeable. Please resolve the merge conflicts.

[Kobzol]

Since we install yarn using npm anyway (so you need to have node + npm to use yarn), and I assume that it will be more common for people to have npm available locally than having yarn, can we just keep the original npm config and use npm in tidy to install yarn, and then use yarn to install the packages?

[jhpratt]

Trying to create rollups, this seems likely to conflict. Bumping priority

@bors p=1 rollup=iffy

[jhpratt]

Actually, I see it already has conflicts, so it needs a rebase.

@bors r-

[rustbot]

This PR was rebased onto a different main 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.

[Kobzol]

Thanks!

@bors r+

[bors]

📌 Commit 58f034f has been approved by Kobzol

It is now in the queue for this repository.

[bors]

⌛ Testing commit 58f034f with merge 66bc5a4...

[bors]

☀️ Test successful - checks-actions
Approved by: Kobzol
Pushing 66bc5a4 to main...

[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 cc328c1 (parent) -> 66bc5a4 (this PR)

Test differences

Show 2 test diffs

2 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 66bc5a43e55eae14a2ec70b11004c88072fe7f02 --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. aarch64-gnu-debug: 4124.3s -> 4941.6s (+19.8%)
2. i686-gnu-1: 8423.7s -> 7035.4s (-16.5%)
3. dist-apple-various: 4093.5s -> 3491.9s (-14.7%)
4. x86_64-gnu-llvm-20-1: 3682.5s -> 3142.8s (-14.7%)
5. x86_64-gnu-llvm-21-3: 6656.1s -> 5706.8s (-14.3%)
6. i686-gnu-2: 6215.1s -> 5388.6s (-13.3%)
7. pr-check-1: 1923.0s -> 1689.3s (-12.2%)
8. x86_64-gnu-gcc: 3522.7s -> 3095.3s (-12.1%)
9. x86_64-gnu-llvm-20: 2766.5s -> 2436.0s (-11.9%)
10. dist-aarch64-apple: 6615.3s -> 7273.1s (+9.9%)

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 (66bc5a4): comparison URL.

Overall result: no relevant changes - no action needed

@rustbot label: -perf-regression

Instruction count

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

Max RSS (memory usage)

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

Cycles

Results (primary 2.0%, secondary -0.7%)

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

	mean	range	count
Regressions ❌ (primary)	2.0%	[2.0%, 2.0%]	1
Regressions ❌ (secondary)	2.4%	[2.4%, 2.4%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-3.7%	[-3.7%, -3.7%]	1
All ❌✅ (primary)	2.0%	[2.0%, 2.0%]	1

Binary size

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

Bootstrap: 474.713s -> 473.832s (-0.19%)
Artifact size: 388.74 MiB -> 388.76 MiB (0.01%)