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diff --git a/vendor/camino/README.md b/vendor/camino/README.md new file mode 100644 index 000000000..9fad93a02 --- /dev/null +++ b/vendor/camino/README.md @@ -0,0 +1,132 @@ +# camino - UTF-8 encoded paths + +[](https://crates.io/crates/camino) +[](https://crates.io/crates/camino) +[](https://docs.rs/camino) +[](https://camino-rs.github.io/camino/rustdoc/camino/) +[](LICENSE-APACHE) +[](LICENSE-MIT) + +This repository contains the source code for `camino`, an extension of the `std::path` module that adds new +[`Utf8PathBuf`] and [`Utf8Path`] types. + +## What is camino? + +`camino`'s [`Utf8PathBuf`] and [`Utf8Path`] types are like the standard library's [`PathBuf`] and [`Path`] types, except +they are guaranteed to only contain UTF-8 encoded data. Therefore, they expose the ability to get their +contents as strings, they implement `Display`, etc. + +The `std::path` types are not guaranteed to be valid UTF-8. This is the right decision for the standard library, +since it must be as general as possible. However, on all platforms, non-Unicode paths are vanishingly uncommon for a +number of reasons: +* Unicode won. There are still some legacy codebases that store paths in encodings like [Shift JIS], but most + have been converted to Unicode at this point. +* Unicode is the common subset of supported paths across Windows and Unix platforms. (On Windows, Rust stores paths + as [an extension to UTF-8](https://simonsapin.github.io/wtf-8/), and converts them to UTF-16 at Win32 + API boundaries.) +* There are already many systems, such as Cargo, that only support UTF-8 paths. If your own tool interacts with any such + system, you can assume that paths are valid UTF-8 without creating any additional burdens on consumers. +* The ["makefile problem"](https://www.mercurial-scm.org/wiki/EncodingStrategy#The_.22makefile_problem.22) asks: given a + Makefile or other metadata file (such as `Cargo.toml`) that lists the names of other files, how should the names in + the Makefile be matched with the ones on disk? This has *no general, cross-platform solution* in systems that support + non-UTF-8 paths. However, restricting paths to UTF-8 eliminates this problem. + +[Shift JIS]: https://en.wikipedia.org/wiki/Shift_JIS + +Therefore, many programs that want to manipulate paths *do* assume they contain UTF-8 data, and convert them to `str`s +as necessary. However, because this invariant is not encoded in the `Path` type, conversions such as +`path.to_str().unwrap()` need to be repeated again and again, creating a frustrating experience. + +Instead, `camino` allows you to check that your paths are UTF-8 *once*, and then manipulate them +as valid UTF-8 from there on, avoiding repeated lossy and confusing conversions. + +## Examples + +The documentation for [`Utf8PathBuf`] and [`Utf8Path`] contains several examples. + +For examples of how to use `camino` with other libraries like `serde` and `clap`, see the [`camino-examples`] directory. + +## API design + +`camino` is a very thin wrapper around `std::path`. [`Utf8Path`] and [`Utf8PathBuf`] are drop-in replacements +for [`Path`] and [`PathBuf`]. + +Most APIs are the same, but those at the boundary with `str` are different. Some examples: +* `Path::to_str() -> Option<&str>` has been renamed to `Utf8Path::as_str() -> &str`. +* [`Utf8Path`] implements `Display`, and `Path::display()` has been removed. +* Iterating over a [`Utf8Path`] returns `&str`, not `&OsStr`. + +Every [`Utf8Path`] is a valid [`Path`], so [`Utf8Path`] implements `AsRef<Path>`. Any APIs that accept `impl AsRef<Path>` +will continue to work with [`Utf8Path`] instances. + +## Should you use camino? + +`camino` trades off some utility for a great deal of simplicity. Whether `camino` is appropriate for a project or not +is ultimately a case-by-case decision. Here are some general guidelines that may help. + +*You should consider using camino if...* + +* **You're building portable, cross-platform software.** While both Unix and Windows platforms support different kinds + of non-Unicode paths, Unicode is the common subset that's supported across them. +* **Your system has files that contain the names of other files.** If you don't use UTF-8 paths, you will run into the + makefile problem described above, which has no general, cross-platform solution. +* **You're interacting with existing systems that already assume UTF-8 paths.** In that case you won't be adding any new + burdens on downstream consumers. +* **You're building something brand new and are willing to ask your users to rename their paths if necessary.** Projects + that don't have to worry about legacy compatibility have more flexibility in choosing what paths they support. + +In general, using camino is the right choice for most projects. + +*You should **NOT** use camino, if...* + +* **You're writing a core system utility.** If you're writing, say, an `mv` or `cat` replacement, you should + **not** use camino. Instead, use [`std::path::Path`] and add extensive tests for non-UTF-8 paths. +* **You have legacy compatibility constraints.** For example, Git supports non-UTF-8 paths. If your tool needs to handle + arbitrary Git repositories, it should use its own path type that's a wrapper around `Vec<u8>`. + * [`std::path::Path`] supports arbitrary bytestrings [on Unix] but not on Windows. +* **There's some other reason you need to support non-UTF-8 paths.** Some tools like disk recovery utilities need to + handle potentially corrupt filenames: only being able to handle UTF-8 paths would greatly diminish their utility. + +[on Unix]: https://doc.rust-lang.org/std/os/unix/ffi/index.html + +## Optional features + +By default, `camino` has **no dependencies** other than `std`. There are some optional features that enable +dependencies: +* `serde1` adds serde [`Serialize`] and [`Deserialize`] impls for [`Utf8PathBuf`] and [`Utf8Path`] + (zero-copy). +* `proptest1` adds [proptest](https://altsysrq.github.io/proptest-book/) [`Arbitrary`] + implementations for [`Utf8PathBuf`] and `Box<Utf8Path>`. + +## Rust version support + +The minimum supported Rust version (MSRV) for `camino` with default features is **1.34**. This project is tested in CI +against the latest stable version of Rust and the MSRV. +* *Stable APIs* added in later Rust versions are supported either through conditional compilation in `build.rs`, or through backfills that also work on older versions. +* *Deprecations* are kept in sync with the version of Rust they're added in. +* *Unstable APIs* are currently not supported. Please + [file an issue on GitHub](https://github.com/camino-rs/camino/issues/new) if you need an unstable API. + +`camino` is designed to be a core library and has a conservative MSRV policy. MSRV increases will only happen for +a compelling enough reason, and will involve at least a minor version bump. + +Optional features may pull in dependencies that require a newer version of Rust. + +## License + +This project is available under the terms of either the [Apache 2.0 license](LICENSE-APACHE) or the [MIT +license](LICENSE-MIT). + +This project's documentation is adapted from [The Rust Programming Language](https://github.com/rust-lang/rust/), which is +available under the terms of either the [Apache 2.0 license](https://github.com/rust-lang/rust/blob/master/LICENSE-APACHE) +or the [MIT license](https://github.com/rust-lang/rust/blob/master/LICENSE-MIT). + +[`Utf8PathBuf`]: https://docs.rs/camino/*/camino/struct.Utf8PathBuf.html +[`Utf8Path`]: https://docs.rs/camino/*/camino/struct.Utf8Path.html +[`PathBuf`]: https://doc.rust-lang.org/std/path/struct.PathBuf.html +[`Path`]: https://doc.rust-lang.org/std/path/struct.Path.html +[`std::path::Path`]: https://doc.rust-lang.org/std/path/struct.Path.html +[`Serialize`]: https://docs.rs/serde/1/serde/trait.Serialize.html +[`Deserialize`]: https://docs.rs/serde/1/serde/trait.Deserialize.html +[`camino-examples`]: https://github.com/camino-rs/camino/tree/main/camino-examples +[`Arbitrary`]: https://docs.rs/proptest/1/proptest/arbitrary/trait.Arbitrary.html |