Merge #110

110: Add ui test for marker_trait_attr feature r=taiki-e a=taiki-e

cc #105 

Co-authored-by: Taiki Endo <te316e89@gmail.com>

Cargo.toml

@@ -23,4 +23,4 @@ members = ["pin-project-internal"]
 pin-project-internal = { version = "=0.4.0", path = "pin-project-internal", default-features = false }
 
 [dev-dependencies]
-compiletest = { version = "0.3.21", package = "compiletest_rs", features = ["stable", "tmp"] }
+compiletest = { version = "=0.3.22", package = "compiletest_rs", features = ["stable", "tmp"] }

tests/ui/unstable-features/marker_trait_attr-feature-gate.rs

@@ -0,0 +1,23 @@
+// compile-fail
+
+// NB: If you change this test, change 'marker_trait_attr.rs' at the same time.
+
+use pin_project::pin_project;
+use std::marker::PhantomPinned;
+
+#[pin_project] //~ ERROR E0119
+struct Foo<T> {
+    #[pin]
+    x: T,
+}
+
+// unsound Unpin impl
+impl<T> Unpin for Foo<T> {}
+
+fn is_unpin<T: Unpin>() {}
+
+fn foo_is_unpin() {
+    is_unpin::<Foo<PhantomPinned>>()
+}
+
+fn main() {}

tests/ui/unstable-features/marker_trait_attr-feature-gate.stderr

@@ -0,0 +1,12 @@
+error[E0119]: conflicting implementations of trait `std::marker::Unpin` for type `Foo<_>`:
+  --> $DIR/marker_trait_attr-feature-gate.rs:8:1
+   |
+8  | #[pin_project] //~ ERROR E0119
+   | ^^^^^^^^^^^^^^ conflicting implementation for `Foo<_>`
+...
+15 | impl<T> Unpin for Foo<T> {}
+   | ------------------------ first implementation here
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0119`.

tests/ui/unstable-features/marker_trait_attr.rs

@@ -0,0 +1,29 @@
+// compile-fail
+
+// NB: If you change this test, change 'marker_trait_attr-feature-gate.rs' at the same time.
+
+// marker_trait_attr
+// Tracking issue: https://github.com/rust-lang/rust/issues/29864
+#![feature(marker_trait_attr)]
+
+// See https://github.com/taiki-e/pin-project/issues/105#issuecomment-535355974
+
+use pin_project::pin_project;
+use std::marker::PhantomPinned;
+
+#[pin_project] //~ ERROR E0119
+struct Foo<T> {
+    #[pin]
+    x: T,
+}
+
+// unsound Unpin impl
+impl<T> Unpin for Foo<T> {}
+
+fn is_unpin<T: Unpin>() {}
+
+fn foo_is_unpin() {
+    is_unpin::<Foo<PhantomPinned>>()
+}
+
+fn main() {}

tests/ui/unstable-features/marker_trait_attr.stderr

@@ -0,0 +1,12 @@
+error[E0119]: conflicting implementations of trait `std::marker::Unpin` for type `Foo<_>`:
+  --> $DIR/marker_trait_attr.rs:14:1
+   |
+14 | #[pin_project] //~ ERROR E0119
+   | ^^^^^^^^^^^^^^ conflicting implementation for `Foo<_>`
+...
+21 | impl<T> Unpin for Foo<T> {}
+   | ------------------------ first implementation here
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0119`.