Rename bstr module/feature to byte_str

[clarfonthey]

This also renames the various features to use byte_str instead of bstr.

[rustbot]

r? @Mark-Simulacrum

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[theemathas]

Can we also have a doc alias or something, so when someone searches for bstr (like the crate name), they also find this?

[clarfonthey]

Thank you for reminding me; I'll add those to the types and the module.

EDIT: The types already have it, so, just the module, then.

[clarfonthey]

Yeah, okay, since the types have this, adding it to the modules is just extra noise:

[clarfonthey]

Note: the rustdoc links are annoying, but I'll finagle a fix for them.

[Mark-Simulacrum]

I assume there's a "why" somewhere for this, can you expand the PR description to include it? The actual code changes seem fine (I guess modulo CI failure :)

[clarfonthey]

Gonna just nominate this so we can discuss this change. I think it's uncontroversial, but worth talking about.

@rustbot label:I-libs-nominated

[clarfonthey]

Discussion in the meeting was that it should be consistent, but before stabilisation we might rename it to bstr::BStr if people want that API instead.

For now, byte_str::ByteStr makes the most sense.

(To be clear, bstr::ByteStr and byte_str::BStr are both undesired.)

[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.

[rust-log-analyzer]

The job aarch64-gnu-llvm-21-2 failed! Check out the build log: (web) (plain enhanced) (plain)

Click to see the possible cause of the failure (guessed by this bot)

##[endgroup]
[TIMING:end] tool::ToolBuild { build_compiler: Compiler { stage: 0, host: aarch64-unknown-linux-gnu, forced_compiler: false }, target: aarch64-unknown-linux-gnu, tool: "linkchecker", path: "src/tools/linkchecker", mode: ToolBootstrap, source_type: InTree, extra_features: [], allow_features: "", cargo_args: [], artifact_kind: Binary } -- 0.103
[TIMING:end] tool::Linkchecker { compiler: Compiler { stage: 0, host: aarch64-unknown-linux-gnu, forced_compiler: false }, target: aarch64-unknown-linux-gnu } -- 0.000
##[group]Testing stage1 Linkcheck (aarch64-unknown-linux-gnu)
core/byte_str/struct.ByteStr.html:53: broken link fragment `#method.to_ascii_uppercase` pointing to `core/byte_str/struct.ByteStr.html`
core/byte_str/struct.ByteStr.html:58: broken link fragment `#method.to_ascii_lowercase` pointing to `core/byte_str/struct.ByteStr.html`
core/byte_str/struct.ByteStr.html:1388: broken link - `core/byte_str/slice::sort_by_key`
alloc/byte_str/struct.ByteStr.html:162: broken link fragment `#method.sort_by_key` pointing to `core/primitive.slice.html`
alloc/byte_str/struct.ByteStr.html:1592: broken link fragment `#method.sort_by_key` pointing to `core/primitive.slice.html`
alloc/byte_str/struct.ByteString.html:1000: broken link fragment `#method.sort_by_key` pointing to `core/primitive.slice.html`
alloc/byte_str/struct.ByteString.html:2369: broken link fragment `#method.sort_by_key` pointing to `core/primitive.slice.html`
NOTE: if you are adding or renaming a markdown file in a mdBook, don't forget to register the page in SUMMARY.md
checked links in: 24.0s
number of HTML files scanned: 62538
number of HTML redirects found: 22220
number of links checked: 2990195
number of links ignored due to external: 186158
---
Command `/checkout/obj/build/aarch64-unknown-linux-gnu/stage1-tools-bin/linkchecker /checkout/obj/build/aarch64-unknown-linux-gnu/doc` failed with exit code 1
Created at: src/bootstrap/src/core/build_steps/tool.rs:1627:23
Executed at: src/bootstrap/src/core/build_steps/test.rs:225:77

Command has failed. Rerun with -v to see more details.
Bootstrap failed while executing `--stage 2 test --skip tidy --skip intrinsic-test --skip src/tools/rust-analyzer --skip tests --skip library --skip tidyselftest`
Currently active steps:
test::Linkcheck { host: aarch64-unknown-linux-gnu } at src/bootstrap/src/core/build_steps/test.rs:162
Build completed unsuccessfully in 0:37:17
  local time: Thu Aug 27 02:54:49 UTC 2026

[clarfonthey]

Right, pretty sure this is blocked by #161699 too

@rustbot blocked