rust/crates/ide-diagnostics/src/handlers/moved_out_of_ref.rs
2023-05-18 19:17:06 +03:30

155 lines
2.6 KiB
Rust

use crate::{Diagnostic, DiagnosticsContext};
use hir::HirDisplay;
// Diagnostic: moved-out-of-ref
//
// This diagnostic is triggered on moving non copy things out of references.
pub(crate) fn moved_out_of_ref(ctx: &DiagnosticsContext<'_>, d: &hir::MovedOutOfRef) -> Diagnostic {
Diagnostic::new(
"moved-out-of-ref",
format!("cannot move `{}` out of reference", d.ty.display(ctx.sema.db)),
ctx.sema.diagnostics_display_range(d.span.clone()).range,
)
.experimental() // spans are broken, and I'm not sure how precise we can detect copy types
}
#[cfg(test)]
mod tests {
use crate::tests::check_diagnostics;
// FIXME: spans are broken
#[test]
fn move_by_explicit_deref() {
check_diagnostics(
r#"
struct X;
fn main() {
let a = &X;
let b = *a;
//^ error: cannot move `X` out of reference
}
"#,
);
}
#[test]
fn move_out_of_field() {
check_diagnostics(
r#"
//- minicore: copy
struct X;
struct Y(X, i32);
fn main() {
let a = &Y(X, 5);
let b = a.0;
//^ error: cannot move `X` out of reference
let y = a.1;
}
"#,
);
}
#[test]
fn move_out_of_static() {
check_diagnostics(
r#"
//- minicore: copy
struct X;
fn main() {
static S: X = X;
let s = S;
//^ error: cannot move `X` out of reference
}
"#,
);
}
#[test]
fn generic_types() {
check_diagnostics(
r#"
//- minicore: derive, copy
#[derive(Copy)]
struct X<T>(T);
struct Y;
fn consume<T>(_: X<T>) {
}
fn main() {
let a = &X(Y);
consume(*a);
//^^^^^^^^^^^ error: cannot move `X<Y>` out of reference
let a = &X(5);
consume(*a);
}
"#,
);
}
#[test]
fn no_false_positive_simple() {
check_diagnostics(
r#"
//- minicore: copy
fn f(_: i32) {}
fn main() {
let x = &2;
f(*x);
}
"#,
);
}
#[test]
fn no_false_positive_unknown_type() {
check_diagnostics(
r#"
//- minicore: derive, copy
fn f(x: &Unknown) -> Unknown {
*x
}
#[derive(Copy)]
struct X<T>(T);
struct Y<T>(T);
fn g(x: &X<Unknown>) -> X<Unknown> {
*x
}
fn h(x: &Y<Unknown>) -> Y<Unknown> {
// FIXME: we should show error for this, as `Y` is not copy
// regardless of its generic parameter.
*x
}
"#,
);
}
#[test]
fn no_false_positive_dyn_fn() {
check_diagnostics(
r#"
//- minicore: copy, fn
fn f(x: &mut &mut dyn Fn()) {
x();
}
struct X<'a> {
field: &'a mut dyn Fn(),
}
fn f(x: &mut X<'_>) {
(x.field)();
}
"#,
);
}
}