Support use self::super as name;

xubo.rs · mu001999 · commit 7bc8c0b32995 · 2026-02-05T21:29:07.000+08:00
diff --git a/compiler/rustc_resolve/src/build_reduced_graph.rs b/compiler/rustc_resolve/src/build_reduced_graph.rs
@@ -643,7 +643,21 @@ impl<'a, 'ra, 'tcx> BuildReducedGraphVisitor<'a, 'ra, 'tcx> {
                         }
                     }
                     kw::Super => {
-                        if module_path.iter().any(|seg| seg.ident.name != kw::Super) {
+                        // Allow the following forms:
+                        // `use super as name;`
+                        // `use super::super as name;`
+                        // `use self::super as name;`
+                        // `use self::super::super as name;`
+                        let valid_prefix = module_path.is_empty()
+                            || matches!(
+                                module_path.first().unwrap().ident.name,
+                                kw::SelfLower | kw::Super
+                            ) && module_path
+                                .iter()
+                                .skip(1)
+                                .all(|seg| seg.ident.name == kw::Super);
+
+                        if !valid_prefix {
                             self.r.dcx().span_err(
                                 source.ident.span,
                                 "`super` in paths can only be used in start position or after another `super`",
diff --git a/tests/ui/use/use-path-segment-kw.e2015.stderr b/tests/ui/use/use-path-segment-kw.e2015.stderr
@@ -234,29 +234,27 @@ help: try renaming it with a name
 LL |         use super::{super as name};
    |                           +++++++
 
-error: `super` in paths can only be used in start position or after another `super`
+error: imports need to be explicitly named
   --> $DIR/use-path-segment-kw.rs:163:19
    |
 LL |         use self::super;
    |                   ^^^^^
-
-error: `super` in paths can only be used in start position or after another `super`
-  --> $DIR/use-path-segment-kw.rs:164:19
    |
-LL |         use self::super as _super6;
-   |                   ^^^^^
+help: try renaming it with a name
+   |
+LL |         use self::super as name;
+   |                         +++++++
 
-error: `super` in paths can only be used in start position or after another `super`
+error: imports need to be explicitly named
   --> $DIR/use-path-segment-kw.rs:165:20
    |
 LL |         use self::{super};
    |                    ^^^^^
-
-error: `super` in paths can only be used in start position or after another `super`
-  --> $DIR/use-path-segment-kw.rs:166:20
    |
-LL |         use self::{super as _nested_super6};
-   |                    ^^^^^
+help: try renaming it with a name
+   |
+LL |         use self::{super as name};
+   |                          +++++++
 
 error: imports need to be explicitly named
   --> $DIR/use-path-segment-kw.rs:173:13
@@ -1185,7 +1183,7 @@ error[E0433]: failed to resolve: `self` in paths can only be used in start posit
 LL |         type D6 = self::self;
    |                         ^^^^ `self` in paths can only be used in start position
 
-error: aborting due to 131 previous errors
+error: aborting due to 129 previous errors
 
 Some errors have detailed explanations: E0429, E0432, E0433, E0573.
 For more information about an error, try `rustc --explain E0429`.
diff --git a/tests/ui/use/use-path-segment-kw.e2018.stderr b/tests/ui/use/use-path-segment-kw.e2018.stderr
@@ -234,29 +234,27 @@ help: try renaming it with a name
 LL |         use super::{super as name};
    |                           +++++++
 
-error: `super` in paths can only be used in start position or after another `super`
+error: imports need to be explicitly named
   --> $DIR/use-path-segment-kw.rs:163:19
    |
 LL |         use self::super;
    |                   ^^^^^
-
-error: `super` in paths can only be used in start position or after another `super`
-  --> $DIR/use-path-segment-kw.rs:164:19
    |
-LL |         use self::super as _super6;
-   |                   ^^^^^
+help: try renaming it with a name
+   |
+LL |         use self::super as name;
+   |                         +++++++
 
-error: `super` in paths can only be used in start position or after another `super`
+error: imports need to be explicitly named
   --> $DIR/use-path-segment-kw.rs:165:20
    |
 LL |         use self::{super};
    |                    ^^^^^
-
-error: `super` in paths can only be used in start position or after another `super`
-  --> $DIR/use-path-segment-kw.rs:166:20
    |
-LL |         use self::{super as _nested_super6};
-   |                    ^^^^^
+help: try renaming it with a name
+   |
+LL |         use self::{super as name};
+   |                          +++++++
 
 error: imports need to be explicitly named
   --> $DIR/use-path-segment-kw.rs:173:13
@@ -939,7 +937,7 @@ LL |         type D7 = crate::foo::bar::self;
    |                                    ^^^^ `self` in paths can only be used in start position
 
 error[E0433]: failed to resolve: could not find `_nested_self2` in `bar`
-  --> $DIR/use-path-segment-kw.rs:239:15
+  --> $DIR/use-path-segment-kw.rs:241:15
    |
 LL |     foo::bar::_nested_self2::outer();
    |               ^^^^^^^^^^^^^ could not find `_nested_self2` in `bar`
@@ -1162,7 +1160,7 @@ error[E0433]: failed to resolve: `self` in paths can only be used in start posit
 LL |         type D6 = self::self;
    |                         ^^^^ `self` in paths can only be used in start position
 
-error: aborting due to 128 previous errors
+error: aborting due to 126 previous errors
 
 Some errors have detailed explanations: E0429, E0433, E0573.
 For more information about an error, try `rustc --explain E0429`.
diff --git a/tests/ui/use/use-path-segment-kw.rs b/tests/ui/use/use-path-segment-kw.rs
@@ -160,10 +160,10 @@ mod foo {
         pub use super::{super as _nested_super5};
 
         type C6 = self::super; //~ ERROR expected type, found module `self::super`
-        use self::super; //~ ERROR `super` in paths can only be used in start position or after another `super`
-        use self::super as _super6; //~ ERROR `super` in paths can only be used in start position or after another `super`
-        use self::{super}; //~ ERROR `super` in paths can only be used in start position or after another `super`
-        use self::{super as _nested_super6}; //~ ERROR `super` in paths can only be used in start position or after another `super`
+        use self::super; //~ ERROR imports need to be explicitly named
+        pub use self::super as _super6;
+        use self::{super}; //~ ERROR imports need to be explicitly named
+        pub use self::{super as _nested_super6};
 
         // --- self ---
         // use self::*; // Suppress other errors
@@ -232,6 +232,8 @@ fn main() {
     foo::bar::_super::bar::foobar::inner();
     foo::bar::_super5::outer();
     foo::bar::_nested_super5::outer();
+    foo::bar::_super6::bar::foobar::inner();
+    foo::bar::_nested_super6::bar::foobar::inner();
 
     foo::bar::_self::foobar::inner();
     foo::bar::qux::inner(); // Works after recovery
