mirror of https://github.com/rust-lang/rust
44 lines
1.2 KiB
Rust
44 lines
1.2 KiB
Rust
#![feature(lazy_cell)]
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#![deny(suspicious_double_ref_op, noop_method_call)]
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use std::borrow::Borrow;
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use std::ops::Deref;
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struct PlainType<T>(T);
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#[derive(Clone)]
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struct CloneType<T>(T);
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pub fn clone_on_double_ref() {
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let x = vec![1];
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let y = &&x;
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let z: &Vec<_> = y.clone();
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//~^ ERROR using `.clone()` on a double reference, which returns `&Vec<i32>`
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println!("{:p} {:p}", *y, z);
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}
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use std::sync::LazyLock;
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pub static STRS: LazyLock<&str> = LazyLock::new(|| "First");
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// https://github.com/rust-lang/rust-clippy/issues/9272
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fn rust_clippy_issue_9272() {
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let str = STRS.clone();
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println!("{str}")
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}
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fn main() {
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let clone_type_ref = &&CloneType(1u32);
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let clone_type_ref_clone: &CloneType<u32> = clone_type_ref.clone();
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//~^ ERROR using `.clone()` on a double reference, which returns `&CloneType<u32>`
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let non_deref_type = &&PlainType(1u32);
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let non_deref_type_deref: &PlainType<u32> = non_deref_type.deref();
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//~^ ERROR using `.deref()` on a double reference, which returns `&PlainType<u32>`
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let xs = ["a", "b", "c"];
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let _v: Vec<&str> = xs.iter().map(|x| x.clone()).collect(); // could use `*x` instead
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//~^ ERROR using `.clone()` on a double reference, which returns `&str`
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}
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