Rollup merge of #98548 - Enselic:allow-typedef-diff-for-rustdoc-json, r=GuillaumeGomez

rustdoc-json: Allow Typedef to be different in sanity assert

Closes #98547

This fix is a natural extension of #98053.

r? `@notriddle`

(Since you reviewed the other PR.)

CC `@GuillaumeGomez`

`@rustbot` labels +A-rustdoc-json +T-rustdoc

Author: matthiaskrgr

src/test/rustdoc-json/assoc_type.rs

@@ -0,0 +1,22 @@
+// Regression test for <https://github.com/rust-lang/rust/issues/98547>.
+
+// @has assoc_type.json
+// @has - "$.index[*][?(@.name=='Trait')]"
+// @has - "$.index[*][?(@.name=='AssocType')]"
+// @has - "$.index[*][?(@.name=='S')]"
+// @has - "$.index[*][?(@.name=='S2')]"
+
+pub trait Trait {
+    type AssocType;
+}
+
+impl<T> Trait for T {
+    type AssocType = Self;
+}
+
+pub struct S;
+
+/// Not needed for the #98547 ICE to occur, but added to maximize the chance of
+/// getting an ICE in the future. See
+/// <https://github.com/rust-lang/rust/pull/98548#discussion_r908219164>
+pub struct S2;