diff options
| -rw-r--r-- | compiler/rustc_lint/messages.ftl | 2 | ||||
| -rw-r--r-- | compiler/rustc_lint/src/drop_forget_useless.rs | 2 | ||||
| -rw-r--r-- | compiler/rustc_lint/src/lints.rs | 3 | ||||
| -rw-r--r-- | tests/ui/lint/forgetting_copy_types-can-fixed.fixed | 22 | ||||
| -rw-r--r-- | tests/ui/lint/forgetting_copy_types-can-fixed.rs | 22 | ||||
| -rw-r--r-- | tests/ui/lint/forgetting_copy_types-can-fixed.stderr | 49 | ||||
| -rw-r--r-- | tests/ui/lint/forgetting_copy_types.stderr | 18 |
7 files changed, 113 insertions, 5 deletions
diff --git a/compiler/rustc_lint/messages.ftl b/compiler/rustc_lint/messages.ftl index 805001718ea..ecd8bafe0ad 100644 --- a/compiler/rustc_lint/messages.ftl +++ b/compiler/rustc_lint/messages.ftl @@ -274,6 +274,8 @@ lint_for_loops_over_fallibles = lint_forgetting_copy_types = calls to `std::mem::forget` with a value that implements `Copy` does nothing .label = argument has type `{$arg_ty}` .note = use `let _ = ...` to ignore the expression or result + .suggestion = use `let _ = ...` to ignore the expression or result + lint_forgetting_references = calls to `std::mem::forget` with a reference instead of an owned value does nothing .label = argument has type `{$arg_ty}` .note = use `let _ = ...` to ignore the expression or result diff --git a/compiler/rustc_lint/src/drop_forget_useless.rs b/compiler/rustc_lint/src/drop_forget_useless.rs index 3166556448b..8b8a8f732e7 100644 --- a/compiler/rustc_lint/src/drop_forget_useless.rs +++ b/compiler/rustc_lint/src/drop_forget_useless.rs @@ -199,7 +199,7 @@ impl<'tcx> LateLintPass<'tcx> for DropForgetUseless { cx.emit_span_lint( FORGETTING_COPY_TYPES, expr.span, - ForgetCopyDiag { arg_ty, label: arg.span }, + ForgetCopyDiag { arg_ty, label: arg.span, sugg }, ); } sym::mem_drop diff --git a/compiler/rustc_lint/src/lints.rs b/compiler/rustc_lint/src/lints.rs index 1c061ce25a6..a91180dfb24 100644 --- a/compiler/rustc_lint/src/lints.rs +++ b/compiler/rustc_lint/src/lints.rs @@ -714,11 +714,12 @@ pub struct ForgetRefDiag<'a> { #[derive(LintDiagnostic)] #[diag(lint_forgetting_copy_types)] -#[note] pub struct ForgetCopyDiag<'a> { pub arg_ty: Ty<'a>, #[label] pub label: Span, + #[subdiagnostic] + pub sugg: IgnoreDropSuggestion, } #[derive(LintDiagnostic)] diff --git a/tests/ui/lint/forgetting_copy_types-can-fixed.fixed b/tests/ui/lint/forgetting_copy_types-can-fixed.fixed new file mode 100644 index 00000000000..c5d65ecc1d4 --- /dev/null +++ b/tests/ui/lint/forgetting_copy_types-can-fixed.fixed @@ -0,0 +1,22 @@ +//@ check-fail +//@ run-rustfix + +#![deny(forgetting_copy_types)] +#![allow(unused_mut)] +#![allow(unused_imports)] + +use std::vec::Vec; +use std::mem::forget; + +#[derive(Copy, Clone)] +struct SomeStruct; + +fn main() { + let s1 = SomeStruct {}; + let s2 = s1; + let mut s3 = s1; + + let _ = s1; //~ ERROR calls to `std::mem::forget` + let _ = s2; //~ ERROR calls to `std::mem::forget` + let _ = s3; //~ ERROR calls to `std::mem::forget` +} diff --git a/tests/ui/lint/forgetting_copy_types-can-fixed.rs b/tests/ui/lint/forgetting_copy_types-can-fixed.rs new file mode 100644 index 00000000000..c5572294280 --- /dev/null +++ b/tests/ui/lint/forgetting_copy_types-can-fixed.rs @@ -0,0 +1,22 @@ +//@ check-fail +//@ run-rustfix + +#![deny(forgetting_copy_types)] +#![allow(unused_mut)] +#![allow(unused_imports)] + +use std::vec::Vec; +use std::mem::forget; + +#[derive(Copy, Clone)] +struct SomeStruct; + +fn main() { + let s1 = SomeStruct {}; + let s2 = s1; + let mut s3 = s1; + + forget(s1); //~ ERROR calls to `std::mem::forget` + forget(s2); //~ ERROR calls to `std::mem::forget` + forget(s3); //~ ERROR calls to `std::mem::forget` +} diff --git a/tests/ui/lint/forgetting_copy_types-can-fixed.stderr b/tests/ui/lint/forgetting_copy_types-can-fixed.stderr new file mode 100644 index 00000000000..cb7bbf02222 --- /dev/null +++ b/tests/ui/lint/forgetting_copy_types-can-fixed.stderr @@ -0,0 +1,49 @@ +error: calls to `std::mem::forget` with a value that implements `Copy` does nothing + --> $DIR/forgetting_copy_types-can-fixed.rs:19:5 + | +LL | forget(s1); + | ^^^^^^^--^ + | | + | argument has type `SomeStruct` + | +note: the lint level is defined here + --> $DIR/forgetting_copy_types-can-fixed.rs:4:9 + | +LL | #![deny(forgetting_copy_types)] + | ^^^^^^^^^^^^^^^^^^^^^ +help: use `let _ = ...` to ignore the expression or result + | +LL - forget(s1); +LL + let _ = s1; + | + +error: calls to `std::mem::forget` with a value that implements `Copy` does nothing + --> $DIR/forgetting_copy_types-can-fixed.rs:20:5 + | +LL | forget(s2); + | ^^^^^^^--^ + | | + | argument has type `SomeStruct` + | +help: use `let _ = ...` to ignore the expression or result + | +LL - forget(s2); +LL + let _ = s2; + | + +error: calls to `std::mem::forget` with a value that implements `Copy` does nothing + --> $DIR/forgetting_copy_types-can-fixed.rs:21:5 + | +LL | forget(s3); + | ^^^^^^^--^ + | | + | argument has type `SomeStruct` + | +help: use `let _ = ...` to ignore the expression or result + | +LL - forget(s3); +LL + let _ = s3; + | + +error: aborting due to 3 previous errors + diff --git a/tests/ui/lint/forgetting_copy_types.stderr b/tests/ui/lint/forgetting_copy_types.stderr index 36d1ef5c53e..a2b07351d79 100644 --- a/tests/ui/lint/forgetting_copy_types.stderr +++ b/tests/ui/lint/forgetting_copy_types.stderr @@ -6,12 +6,16 @@ LL | forget(s1); | | | argument has type `SomeStruct` | - = note: use `let _ = ...` to ignore the expression or result note: the lint level is defined here --> $DIR/forgetting_copy_types.rs:3:9 | LL | #![warn(forgetting_copy_types)] | ^^^^^^^^^^^^^^^^^^^^^ +help: use `let _ = ...` to ignore the expression or result + | +LL - forget(s1); +LL + let _ = s1; + | warning: calls to `std::mem::forget` with a value that implements `Copy` does nothing --> $DIR/forgetting_copy_types.rs:35:5 @@ -21,7 +25,11 @@ LL | forget(s2); | | | argument has type `SomeStruct` | - = note: use `let _ = ...` to ignore the expression or result +help: use `let _ = ...` to ignore the expression or result + | +LL - forget(s2); +LL + let _ = s2; + | warning: calls to `std::mem::forget` with a reference instead of an owned value does nothing --> $DIR/forgetting_copy_types.rs:36:5 @@ -42,7 +50,11 @@ LL | forget(s4); | | | argument has type `SomeStruct` | - = note: use `let _ = ...` to ignore the expression or result +help: use `let _ = ...` to ignore the expression or result + | +LL - forget(s4); +LL + let _ = s4; + | warning: calls to `std::mem::forget` with a reference instead of an owned value does nothing --> $DIR/forgetting_copy_types.rs:38:5 |