Add tests for new tyalias intra-doc link disambiguator

Author: GuillaumeGomez

tests/rustdoc-ui/intra-doc/type-alias-primitive-suggestion.rs

@@ -0,0 +1,15 @@
+// Ensure that no warning is emitted if the disambiguator is used for type alias.
+// Regression test for <https://github.com/rust-lang/rust/issues/146855>.
+
+#![deny(rustdoc::broken_intra_doc_links)]
+
+pub struct Foo;
+
+#[allow(non_camel_case_types)]
+pub type f32 = Foo;
+
+/// This function returns [`f32`].
+//~^ ERROR: `f32` is both a type alias and a primitive type
+//~| HELP: to link to the type alias, prefix with `tyalias@`
+//~| HELP: to link to the primitive type, prefix with `prim@`
+pub fn my_fn() -> f32 {}

tests/rustdoc-ui/intra-doc/type-alias-primitive-suggestion.stderr

@@ -0,0 +1,22 @@
+error: `f32` is both a type alias and a primitive type
+  --> $DIR/type-alias-primitive-suggestion.rs:11:29
+   |
+LL | /// This function returns [`f32`].
+   |                             ^^^ ambiguous link
+   |
+note: the lint level is defined here
+  --> $DIR/type-alias-primitive-suggestion.rs:4:9
+   |
+LL | #![deny(rustdoc::broken_intra_doc_links)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+help: to link to the type alias, prefix with `tyalias@`
+   |
+LL | /// This function returns [`tyalias@f32`].
+   |                             ++++++++
+help: to link to the primitive type, prefix with `prim@`
+   |
+LL | /// This function returns [`prim@f32`].
+   |                             +++++
+
+error: aborting due to 1 previous error
+

tests/rustdoc-ui/intra-doc/type-alias-primitive.rs

@@ -0,0 +1,14 @@
+// Ensure that no warning is emitted if the disambiguator is used for type alias.
+// Regression test for <https://github.com/rust-lang/rust/issues/146855>.
+
+//@ check-pass
+
+#![deny(rustdoc::broken_intra_doc_links)]
+
+pub struct Foo;
+
+#[allow(non_camel_case_types)]
+pub type f32 = Foo;
+
+/// This function returns [`tyalias@f32`] and not [`prim@f32`].
+pub fn my_fn() -> f32 {}

tests/rustdoc/intra-doc/type-alias-primitive.rs

@@ -0,0 +1,15 @@
+// Ensure that no warning is emitted if the disambiguator is used for type alias.
+// Regression test for <https://github.com/rust-lang/rust/issues/146855>.
+
+#![crate_name = "foo"]
+
+pub struct Foo;
+
+#[allow(non_camel_case_types)]
+pub type f32 = Foo;
+
+/// This function returns [`tyalias@f32`] and not [bla][`prim@f32`].
+//@ has 'foo/fn.my_fn.html'
+//@ has - '//a[@href="type.f32.html"]' "f32"
+//@ has - '//a[@href="https://doc.rust-lang.org/nightly/std/primitive.f32.html"]' "bla"
+pub fn my_fn() -> f32 {}