Auto merge of rust-lang#17352 - roife:fix-issue-17338, r=Veykril

fix: do not resolve prelude within block modules

fix rust-lang#17338 (continuing from rust-lang#17251).

In rust-lang#17251, we injected preludes into non-top-level modules, which leading to r-a to directly resolve names in preludes in block modules. This PR fix it by checking whether the module is a pseudo-module introduced by blocks. (similar to what we do for extern preludes)

src/tools/rust-analyzer/crates/hir-def/src/nameres/path_resolution.rs

@@ -493,7 +493,12 @@ impl DefMap {
                 )
             })
         };
-        let prelude = || self.resolve_in_prelude(db, name);
+        let prelude = || {
+            if self.block.is_some() && module == DefMap::ROOT {
+                return PerNs::none();
+            }
+            self.resolve_in_prelude(db, name)
+        };
 
         from_legacy_macro
             .or(from_scope_or_builtin)

src/tools/rust-analyzer/crates/ide/src/goto_definition.rs

@@ -2289,4 +2289,28 @@ macro_rules! baz {
             "#,
         );
     }
+
+    #[test]
+    fn goto_shadowed_preludes_in_block_module() {
+        check(
+            r#"
+//- /main.rs crate:main edition:2021 deps:core
+pub struct S;
+         //^
+
+fn main() {
+    fn f() -> S$0 {
+        fn inner() {} // forces a block def map
+        return S;
+    }
+}
+//- /core.rs crate:core
+pub mod prelude {
+    pub mod rust_2021 {
+        pub enum S;
+    }
+}
+        "#,
+        );
+    }
 }