Let String pass #[track_caller] to its Vec calls

[kornelski]

I've added #[track_caller] to String methods that delegate to Vec methods that already have #[track_caller].

I've also added #[track_caller] to methods that have assert! or panic! due to invalid inputs.

[rustbot]

r? @tgross35

rustbot has assigned @tgross35.
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

[tgross35]

Since this sometimes increases compile times

@bors2 try
@rust-timer queue

[rust-bors]

⌛ Trying commit c109b28 with merge 075cf9a…

To cancel the try build, run the command @bors2 try cancel.

[rust-bors]

☀️ Try build successful (CI)
Build commit: 075cf9a (075cf9a3e6ff4d06acf01becd0b8e06b926329e1, parent: 2fcf1776b9ccef89993dfe40e9f5c4908e2d2d48)

[tgross35]

Mind posting a difference in output with and without this change for reference?

[rust-timer]

Finished benchmarking commit (075cf9a): comparison URL.

Overall result: ✅ 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
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.4%	[-0.4%, -0.4%]	1
All ❌✅ (primary)	-	-	0

Max RSS (memory usage)

Results (primary 0.4%)

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

	mean	range	count
Regressions ❌ (primary)	2.8%	[2.8%, 2.8%]	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-2.0%	[-2.0%, -2.0%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.4%	[-2.0%, 2.8%]	2

Cycles

Results (secondary 4.6%)

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)	4.6%	[4.6%, 4.6%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Binary size

Results (primary 0.1%, secondary 0.3%)

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

	mean	range	count
Regressions ❌ (primary)	0.1%	[0.0%, 0.3%]	12
Regressions ❌ (secondary)	0.3%	[0.0%, 0.4%]	5
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.1%	[0.0%, 0.3%]	12

Bootstrap: 692.244s -> 692.328s (0.01%)
Artifact size: 371.99 MiB -> 372.07 MiB (0.02%)

[kornelski]

old:

thread 'main' panicked at ~/.rustup/toolchains/nightly-aarch64-apple-darwin/lib/rustlib/src/rust/library/alloc/src/string.rs:1461:13:
assertion failed: self.is_char_boundary(new_len)

new:

thread 'main' panicked at src/main.rs:8:7:
assertion failed: self.is_char_boundary(new_len)

[tgross35]

Perf looks okay and the message is indeed much better, thank you!

@bors r+

[bors]

📌 Commit c109b28 has been approved by tgross35

It is now in the queue for this repository.

[bors]

⌛ Testing commit c109b28 with merge 8387d61...

[bors]

☀️ Test successful - checks-actions
Approved by: tgross35
Pushing 8387d61 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 be19eda (parent) -> 8387d61 (this PR)

Test differences

Show 104 test diffs

104 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 8387d61a6ec05faee58f7cfb9c10799285067934 --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. x86_64-apple-1: 11062.1s -> 6726.2s (-39.2%)
2. dist-x86_64-apple: 8900.1s -> 8198.2s (-7.9%)
3. mingw-check-2: 1900.2s -> 2039.3s (7.3%)
4. mingw-check-tidy: 77.9s -> 72.3s (-7.3%)
5. dist-ohos-armv7: 4194.0s -> 3892.8s (-7.2%)
6. x86_64-apple-2: 3566.7s -> 3312.0s (-7.1%)
7. x86_64-gnu-llvm-19-2: 6050.4s -> 5663.6s (-6.4%)
8. arm-android: 5463.5s -> 5164.8s (-5.5%)
9. test-various: 4493.4s -> 4250.3s (-5.4%)
10. x86_64-msvc-2: 6968.8s -> 6615.7s (-5.1%)

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 (8387d61): 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)	-2.9%	[-2.9%, -2.9%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-2.9%	[-2.9%, -2.9%]	1

Max RSS (memory usage)

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

Cycles

Results (primary -2.4%)

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)	-2.4%	[-2.4%, -2.4%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-2.4%	[-2.4%, -2.4%]	1

Binary size

Results (primary -0.0%, secondary 0.2%)

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

	mean	range	count
Regressions ❌ (primary)	0.1%	[0.0%, 0.3%]	11
Regressions ❌ (secondary)	0.2%	[0.0%, 0.3%]	2
Improvements ✅ (primary)	-1.1%	[-1.1%, -1.1%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-0.0%	[-1.1%, 0.3%]	12

Bootstrap: 689.346s -> 689.715s (0.05%)
Artifact size: 371.89 MiB -> 371.92 MiB (0.01%)