Vendor things

third-party/vendor/scopeguard/README.md

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+# scopeguard
+
+Rust crate for a convenient RAII scope guard that will run a given closure when
+it goes out of scope, even if the code between panics (assuming unwinding panic).
+
+The `defer!` macro and `guard` are `no_std` compatible (require only `core`),
+but the on unwinding / not on unwinding strategies require linking to `std`.
+By default, the `use_std` crate feature is enabled. Disable the default features
+for `no_std` support.
+
+Please read the [API documentation here](https://docs.rs/scopeguard/).
+
+Minimum supported Rust version: 1.20
+
+[![build_status](https://github.com/bluss/scopeguard/actions/workflows/ci.yaml/badge.svg)](https://github.com/bluss/scopeguard/actions/workflows/ci.yaml)
+[![crates](https://img.shields.io/crates/v/scopeguard.svg)](https://crates.io/crates/scopeguard)
+
+## How to use
+
+```rs
+#[macro_use(defer)]
+extern crate scopeguard;
+
+use scopeguard::guard;
+
+fn f() {
+    defer! {
+        println!("Called at return or panic");
+    }
+    panic!();
+}
+
+use std::fs::File;
+use std::io::Write;
+
+fn g() {
+    let f = File::create("newfile.txt").unwrap();
+    let mut file = guard(f, |f| {
+        // write file at return or panic
+        let _ = f.sync_all();
+    });
+    // access the file through the scope guard itself
+    file.write_all(b"test me\n").unwrap();
+}
+```
+
+## Recent Changes
+
+- 1.2.0
+
+  - Use ManuallyDrop instead of mem::forget in into_inner. (by @willtunnels)
+  - Warn if the guard is not assigned to a variable and is dropped immediately
+    instead of at the scope's end. (by @sergey-v-galtsev)
+
+- 1.1.0
+
+  - Change macros (`defer!`, `defer_on_success!` and `defer_on_unwind!`)
+    to accept statements. (by @konsumlamm)
+
+- 1.0.0
+
+  - Change the closure type from `FnMut(&mut T)` to `FnOnce(T)`:
+    Passing the inner value by value instead of a mutable reference is a
+    breaking change, but allows the guard closure to consume it. (by @tormol)
+
+  - Add `defer_on_success!`, `guard_on_success()` and `OnSuccess`
+    strategy, which triggers when scope is exited *without* panic. It's the
+    opposite to `defer_on_unwind!` / `guard_on_unwind()` / `OnUnwind`.
+
+  - Add `ScopeGuard::into_inner()`, which "defuses" the guard and returns the
+    guarded value. (by @tormol)
+
+  - Implement `Sync` for guards with non-`Sync` closures.
+
+  - Require Rust 1.20
+
+- 0.3.3
+
+  - Use `#[inline]` on a few more functions by @stjepang (#14)
+  - Add examples to crate documentation
+
+- 0.3.2
+
+  - Add crate categories
+
+- 0.3.1
+
+  - Add `defer_on_unwind!`, `Strategy` trait
+  - Rename `Guard` → `ScopeGuard`
+  - Add `ScopeGuard::with_strategy`.
+  - `ScopeGuard` now implements `Debug`.
+  - Require Rust 1.11
+
+- 0.2.0
+
+  - Require Rust 1.6
+  - Use `no_std` unconditionally
+  - No other changes
+
+- 0.1.2
+
+  - Add macro `defer!`