Warn on unused doc(hidden) on trait impl items

3 files changed, 151 insertions, 0 deletions

diff --git a/src/test/ui/lint/unused/unused-attr-doc-hidden.fixed b/src/test/ui/lint/unused/unused-attr-doc-hidden.fixed
new file mode 100644
index 00000000000..36a14097ac3
--- /dev/null
+++ b/src/test/ui/lint/unused/unused-attr-doc-hidden.fixed
@@ -0,0 +1,42 @@
+#![deny(unused_attributes)]
+#![crate_type = "lib"]
+// run-rustfix
+
+pub trait Trait {
+    type It;
+    const IT: ();
+    fn it0();
+    fn it1();
+    fn it2();
+}
+
+pub struct Implementor;
+
+impl Trait for Implementor {
+    
+    type It = ();
+    //~^^ ERROR `#[doc(hidden)]` is ignored
+    //~|  WARNING this was previously accepted
+
+    
+    const IT: () = ();
+    //~^^ ERROR `#[doc(hidden)]` is ignored
+    //~|  WARNING this was previously accepted
+
+    #[doc(alias = "aka")]
+    fn it0() {}
+    //~^^ ERROR `#[doc(hidden)]` is ignored
+    //~|  WARNING this was previously accepted
+
+    #[doc(alias = "this", )]
+    fn it1() {}
+    //~^^ ERROR `#[doc(hidden)]` is ignored
+    //~|  WARNING this was previously accepted
+
+    #[doc()]
+    fn it2() {}
+    //~^^ ERROR `#[doc(hidden)]` is ignored
+    //~|  WARNING this was previously accepted
+    //~|  ERROR `#[doc(hidden)]` is ignored
+    //~|  WARNING this was previously accepted
+}
diff --git a/src/test/ui/lint/unused/unused-attr-doc-hidden.rs b/src/test/ui/lint/unused/unused-attr-doc-hidden.rs
new file mode 100644
index 00000000000..e58c4f22f31
--- /dev/null
+++ b/src/test/ui/lint/unused/unused-attr-doc-hidden.rs
@@ -0,0 +1,42 @@
+#![deny(unused_attributes)]
+#![crate_type = "lib"]
+// run-rustfix
+
+pub trait Trait {
+    type It;
+    const IT: ();
+    fn it0();
+    fn it1();
+    fn it2();
+}
+
+pub struct Implementor;
+
+impl Trait for Implementor {
+    #[doc(hidden)]
+    type It = ();
+    //~^^ ERROR `#[doc(hidden)]` is ignored
+    //~|  WARNING this was previously accepted
+
+    #[doc(hidden)]
+    const IT: () = ();
+    //~^^ ERROR `#[doc(hidden)]` is ignored
+    //~|  WARNING this was previously accepted
+
+    #[doc(hidden, alias = "aka")]
+    fn it0() {}
+    //~^^ ERROR `#[doc(hidden)]` is ignored
+    //~|  WARNING this was previously accepted
+
+    #[doc(alias = "this", hidden,)]
+    fn it1() {}
+    //~^^ ERROR `#[doc(hidden)]` is ignored
+    //~|  WARNING this was previously accepted
+
+    #[doc(hidden, hidden)]
+    fn it2() {}
+    //~^^ ERROR `#[doc(hidden)]` is ignored
+    //~|  WARNING this was previously accepted
+    //~|  ERROR `#[doc(hidden)]` is ignored
+    //~|  WARNING this was previously accepted
+}
diff --git a/src/test/ui/lint/unused/unused-attr-doc-hidden.stderr b/src/test/ui/lint/unused/unused-attr-doc-hidden.stderr
new file mode 100644
index 00000000000..fd1202a29de
--- /dev/null
+++ b/src/test/ui/lint/unused/unused-attr-doc-hidden.stderr
@@ -0,0 +1,67 @@
+error: `#[doc(hidden)]` is ignored on trait impl items
+  --> $DIR/unused-attr-doc-hidden.rs:16:5
+   |
+LL |     #[doc(hidden)]
+   |     ^^^^^^^^^^^^^^ help: remove this attribute
+   |
+note: the lint level is defined here
+  --> $DIR/unused-attr-doc-hidden.rs:1:9
+   |
+LL | #![deny(unused_attributes)]
+   |         ^^^^^^^^^^^^^^^^^
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: whether the impl item is `doc(hidden)` or not entirely depends on the corresponding trait item
+
+error: `#[doc(hidden)]` is ignored on trait impl items
+  --> $DIR/unused-attr-doc-hidden.rs:21:5
+   |
+LL |     #[doc(hidden)]
+   |     ^^^^^^^^^^^^^^ help: remove this attribute
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: whether the impl item is `doc(hidden)` or not entirely depends on the corresponding trait item
+
+error: `#[doc(hidden)]` is ignored on trait impl items
+  --> $DIR/unused-attr-doc-hidden.rs:26:11
+   |
+LL |     #[doc(hidden, alias = "aka")]
+   |           ^^^^^^--
+   |           |
+   |           help: remove this attribute
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: whether the impl item is `doc(hidden)` or not entirely depends on the corresponding trait item
+
+error: `#[doc(hidden)]` is ignored on trait impl items
+  --> $DIR/unused-attr-doc-hidden.rs:31:27
+   |
+LL |     #[doc(alias = "this", hidden,)]
+   |                           ^^^^^^-
+   |                           |
+   |                           help: remove this attribute
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: whether the impl item is `doc(hidden)` or not entirely depends on the corresponding trait item
+
+error: `#[doc(hidden)]` is ignored on trait impl items
+  --> $DIR/unused-attr-doc-hidden.rs:36:11
+   |
+LL |     #[doc(hidden, hidden)]
+   |           ^^^^^^--
+   |           |
+   |           help: remove this attribute
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: whether the impl item is `doc(hidden)` or not entirely depends on the corresponding trait item
+
+error: `#[doc(hidden)]` is ignored on trait impl items
+  --> $DIR/unused-attr-doc-hidden.rs:36:19
+   |
+LL |     #[doc(hidden, hidden)]
+   |                   ^^^^^^ help: remove this attribute
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: whether the impl item is `doc(hidden)` or not entirely depends on the corresponding trait item
+
+error: aborting due to 6 previous errors
+