74 lines
1.3 KiB
Rust
74 lines
1.3 KiB
Rust
//@aux-build: proc_macros.rs:proc-macro
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#![allow(dead_code, unused_variables)]
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extern crate proc_macros;
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use proc_macros::with_span;
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fn main() {}
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mod should_lint {
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fn one_help() {
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let a = &12;
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let b = a;
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let b = &mut bar(&12);
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}
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fn bar(x: &u32) -> &u32 {
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x
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}
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}
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// this mod explains why we should not lint `&mut &* (&T)`
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mod should_not_lint1 {
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fn foo(x: &mut &u32) {
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*x = &1;
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}
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fn main() {
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let mut x = &0;
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foo(&mut &*x); // should not lint
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assert_eq!(*x, 0);
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foo(&mut x);
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assert_eq!(*x, 1);
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}
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}
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// similar to should_not_lint1
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mod should_not_lint2 {
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struct S<'a> {
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a: &'a u32,
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b: u32,
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}
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fn main() {
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let s = S { a: &1, b: 1 };
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let x = &mut &*s.a;
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*x = &2;
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}
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}
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with_span!(
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span
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fn just_returning(x: &u32) -> &u32 {
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x
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}
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fn dont_lint_proc_macro() {
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let a = &mut &*just_returning(&12);
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}
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);
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// this mod explains why we should not lint `& &* (&T)`
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mod false_negative {
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fn foo() {
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let x = &12;
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let addr_x = &x as *const _ as usize;
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let addr_y = &x as *const _ as usize; // assert ok
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// let addr_y = &x as *const _ as usize; // assert fail
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assert_ne!(addr_x, addr_y);
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}
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}
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