Skip to content

internal: error on duplicate #[pin] attribute #120

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
mentonin wants to merge 2 commits into
base: main
Choose a base branch
from
Open

internal: error on duplicate #[pin] attribute #120

Show file tree
Hide file tree
Changes from 1 commit
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
cc88d52
internal: error on duplicate `#[pin]` attribute
mentonin Mar 11, 2026
8d023c3
internal: update duplicate `#[pin]` error message
mentonin Mar 12, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
8 changes: 6 additions & 2 deletions internal/src/pin_data.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -79,9 +79,13 @@ pub(crate) fn pin_data(
.map(|field| {
let len = field.attrs.len();
field.attrs.retain(|a| !a.path().is_ident("pin"));
(len != field.attrs.len(), &*field)
let diff = len - field.attrs.len();
if diff > 1 {
return Err(dcx.error(field, "#[pin] attribute set twice"));
Comment thread
mentonin marked this conversation as resolved.
Outdated
}
Ok((diff > 0, &*field))
})
.collect();
.collect::<Result<_, _>>()?;

for (pinned, field) in &fields {
if !pinned && is_phantom_pinned(&field.ty) {
Expand Down
10 changes: 10 additions & 0 deletions tests/ui/compile-fail/pin_data/twice_pin.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,10 @@
use pin_init::*;

#[pin_data]
struct Foo {
#[pin]
#[pin]
a: usize,
}

fn main() {}
Copy link
Copy Markdown
Member

@nbdd0121 nbdd0121 Apr 14, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

If you add a user of Foo here, you should observe the "cascading error" effect

5 changes: 5 additions & 0 deletions tests/ui/compile-fail/pin_data/twice_pin.stderr
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,5 @@
error: #[pin] attribute set twice
--> tests/ui/compile-fail/pin_data/twice_pin.rs:7:5
|
7 | a: usize,
| ^^^^^^^^
Loading