Repository: rust-lang/rust-analyzer (rust)

Issue:
`expand glob import` should expand to all possible items without filtering for `pub use` reexports.
**rust-analyzer version**:  `0.4.1255-standalone`
**rustc version**: `rustc 1.66.0-nightly (3f83906b3 2022-09-24)`

```rust
mod qqq {
    use super::*;

    pub trait Tr1{}
    pub trait Tr2{}
    pub struct St1{}
    pub struct St2{}
    pub enum En1{}
}

pub use qqq::┃*;
```

After "expand glob import", I expect.

```rust
mod qqq {
    use super::*;

    pub trait Tr1{}
    pub trait Tr2{}
    pub struct St1{}
    pub struct St2{}
    pub enum En1{}
}

pub use qqq::┃{Tr1, Tr2, St1, St2, En1};
```

but I get:


```rust
mod qqq {
    use super::*;

    pub trait Tr1{}
    pub trait Tr2{}
    pub struct St1{}
    pub struct St2{}
    pub enum En1{}
}

pub use qqq::┃{};
```

Unless RA is willing to analyse the whole workspace for which reexports are actually needed, I think it should just expand to everything. This would allow for easy gradual refactor by moving chunks of code to separate files without also having multiple glob imports one after another.

Alternatively, a second, simpler code assist "Expand glob import (all items)" can be added.

Workaround: Use Ctrl+Space, Enter, Comma, Ctrl+Space, Enter, Comma, ... repeatedly until it offers `self.`

Pull request description:
Implement expand_glob_reexport assist
Fixes #13511 .

The code ends up pretty messy. To handle this more cleanly, I'd want some equivalent of `hir_def::visibility::Visibility::is_visible_from` that takes a `syntax::ast::Visibility` as the origin, or at least some type that can be easily derived from `syntax::ast::Visibility`.

The general problem (from my naive viewpoint as someone unfamiliar with the codebase) is that as far as I can tell the HIR data types you can get from `ctx.sema` already lost all knowledge about `use xxx` items; and those data types are the ones that can do fancy visibility computation. (`hir_def::item_tree::Use` would be useful, but I haven't found a way to get one from a `syntax::ast::Use`)

Anyway, 99% of re-exports are `pub` or `pub(crate)` anyway, so this should already be a large improvement.

Patch:
diff --git a/crates/ide-assists/src/handlers/expand_glob_import.rs b/crates/ide-assists/src/handlers/expand_glob_import.rs
index 094fdc46eb..0b95d6177f 100644
--- a/crates/ide-assists/src/handlers/expand_glob_import.rs
+++ b/crates/ide-assists/src/handlers/expand_glob_import.rs
@@ -3,10 +3,11 @@ use hir::{AssocItem, Enum, HasVisibility, Module, ModuleDef, Name, PathResolutio
 use ide_db::{
     defs::{Definition, NameRefClass},
     search::SearchScope,
+    source_change::SourceChangeBuilder,
 };
 use stdx::never;
 use syntax::{
-    ast::{self, make},
+    ast::{self, make, Use, UseTree, VisibilityKind},
     ted, AstNode, Direction, SyntaxNode, SyntaxToken, T,
 };
 
@@ -43,6 +44,7 @@ use crate::{
 pub(crate) fn expand_glob_import(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<()> {
     let star = ctx.find_token_syntax_at_offset(T![*])?;
     let use_tree = star.parent().and_then(ast::UseTree::cast)?;
+    let use_item = star.parent_ancestors().find_map(ast::Use::cast)?;
     let (parent, mod_path) = find_parent_and_path(&star)?;
     let target_module = match ctx.sema.resolve_path(&mod_path)? {
         PathResolution::Def(ModuleDef::Module(it)) => Expandable::Module(it),
@@ -53,8 +55,9 @@ pub(crate) fn expand_glob_import(acc: &mut Assists, ctx: &AssistContext<'_>) ->
     let current_scope = ctx.sema.scope(&star.parent()?)?;
     let current_module = current_scope.module();
 
-    let refs_in_target = find_refs_in_mod(ctx, target_module, current_module)?;
-    let imported_defs = find_imported_defs(ctx, star)?;
+    if !is_visible_from(ctx, &target_module, current_module) {
+        return None;
+    }
 
     let target = parent.either(|n| n.syntax().clone(), |n| n.syntax().clone());
     acc.add(
@@ -62,37 +65,149 @@ pub(crate) fn expand_glob_import(acc: &mut Assists, ctx: &AssistContext<'_>) ->
         "Expand glob import",
         target.text_range(),
         |builder| {
-            let use_tree = builder.make_mut(use_tree);
-
-            let names_to_import = find_names_to_import(ctx, refs_in_target, imported_defs);
-            let expanded = make::use_tree_list(names_to_import.iter().map(|n| {
-                let path = make::ext::ident_path(
-                    &n.display(ctx.db(), current_module.krate().edition(ctx.db())).to_string(),
-                );
-                make::use_tree(path, None, None, false)
-            }))
-            .clone_for_update();
-
-            match use_tree.star_token() {
-                Some(star) => {
-                    let needs_braces = use_tree.path().is_some() && names_to_import.len() != 1;
-                    if needs_braces {
-                        ted::replace(star, expanded.syntax())
-                    } else {
-                        let without_braces = expanded
-                            .syntax()
-                            .children_with_tokens()
-                            .filter(|child| !matches!(child.kind(), T!['{'] | T!['}']))
-                            .collect();
-                        ted::replace_with_many(star, without_braces)
-                    }
-                }
-                None => never!(),
-            }
+            build_expanded_import(
+                ctx,
+                builder,
+                use_tree,
+                use_item,
+                target_module,
+                current_module,
+                false,
+            )
+        },
+    )
+}
+
+// Assist: expand_glob_reexport
+//
+// Expands non-private glob imports.
+//
+// ```
+// mod foo {
+//     pub struct Bar;
+//     pub struct Baz;
+// }
+//
+// pub use foo::*$0;
+// ```
+// ->
+// ```
+// mod foo {
+//     pub struct Bar;
+//     pub struct Baz;
+// }
+//
+// pub use foo::{Bar, Baz};
+// ```
+pub(crate) fn expand_glob_reexport(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<()> {
+    let star = ctx.find_token_syntax_at_offset(T![*])?;
+    let use_tree = star.parent().and_then(ast::UseTree::cast)?;
+    let use_item = star.parent_ancestors().find_map(ast::Use::cast)?;
+    let (parent, mod_path) = find_parent_and_path(&star)?;
+    let target_module = match ctx.sema.resolve_path(&mod_path)? {
+        PathResolution::Def(ModuleDef::Module(it)) => Expandable::Module(it),
+        PathResolution::Def(ModuleDef::Adt(hir::Adt::Enum(e))) => Expandable::Enum(e),
+        _ => return None,
+    };
+
+    let current_scope = ctx.sema.scope(&star.parent()?)?;
+    let current_module = current_scope.module();
+
+    if let VisibilityKind::PubSelf = get_export_visibility_kind(&use_item) {
+        return None;
+    }
+    if !is_visible_from(ctx, &target_module, current_module) {
+        return None;
+    }
+
+    let target = parent.either(|n| n.syntax().clone(), |n| n.syntax().clone());
+    acc.add(
+        AssistId("expand_glob_reexport", AssistKind::RefactorRewrite),
+        "Expand glob reexport",
+        target.text_range(),
+        |builder| {
+            build_expanded_import(
+                ctx,
+                builder,
+                use_tree,
+                use_item,
+                target_module,
+                current_module,
+                true,
+            )
         },
     )
 }
 
+fn build_expanded_import(
+    ctx: &AssistContext<'_>,
+    builder: &mut SourceChangeBuilder,
+    use_tree: UseTree,
+    use_item: Use,
+    target_module: Expandable,
+    current_module: Module,
+    reexport_public_items: bool,
+) {
+    let (must_be_pub, visible_from) = if !reexport_public_items {
+        (false, current_module)
+    } else {
+        match get_export_visibility_kind(&use_item) {
+            VisibilityKind::Pub => (true, current_module.krate().root_module()),
+            VisibilityKind::PubCrate => (false, current_module.krate().root_module()),
+            _ => (false, current_module),
+        }
+    };
+
+    let refs_in_target = find_refs_in_mod(ctx, target_module, visible_from, must_be_pub);
+    let imported_defs = find_imported_defs(ctx, use_item);
+
+    let filtered_defs =
+        if reexport_public_items { refs_in_target } else { refs_in_target.used_refs(ctx) };
+
+    let use_tree = builder.make_mut(use_tree);
+
+    let names_to_import = find_names_to_import(filtered_defs, imported_defs);
+    let expanded = make::use_tree_list(names_to_import.iter().map(|n| {
+        let path = make::ext::ident_path(
+            &n.display(ctx.db(), current_module.krate().edition(ctx.db())).to_string(),
+        );
+        make::use_tree(path, None, None, false)
+    }))
+    .clone_for_update();
+
+    match use_tree.star_token() {
+        Some(star) => {
+            let needs_braces = use_tree.path().is_some() && names_to_import.len() != 1;
+            if needs_braces {
+                ted::replace(star, expanded.syntax())
+            } else {
+                let without_braces = expanded
+                    .syntax()
+                    .children_with_tokens()
+                    .filter(|child| !matches!(child.kind(), T!['{'] | T!['}']))
+                    .collect();
+                ted::replace_with_many(star, without_braces)
+            }
+        }
+        None => never!(),
+    }
+}
+
+fn get_export_visibility_kind(use_item: &Use) -> VisibilityKind {
+    use syntax::ast::HasVisibility as _;
+    match use_item.visibility() {
+        Some(vis) => match vis.kind() {
+            VisibilityKind::PubCrate => VisibilityKind::PubCrate,
+            VisibilityKind::Pub => VisibilityKind::Pub,
+            VisibilityKind::PubSelf => VisibilityKind::PubSelf,
+            // We don't handle pub(in ...) and pub(super) yet
+            VisibilityKind::In(_) => VisibilityKind::PubSelf,
+            VisibilityKind::PubSuper => VisibilityKind::PubSelf,
+        },
+        None => VisibilityKind::PubSelf,
+    }
+}
+
 enum Expandable {
     Module(Module),
     Enum(Enum),
@@ -130,14 +245,17 @@ struct Ref {
     // could be alias
     visible_name: Name,
     def: Definition,
+    is_pub: bool,
 }
 
 impl Ref {
-    fn from_scope_def(name: Name, scope_def: ScopeDef) -> Option<Self> {
+    fn from_scope_def(ctx: &AssistContext<'_>, name: Name, scope_def: ScopeDef) -> Option<Self> {
         match scope_def {
-            ScopeDef::ModuleDef(def) => {
-                Some(Ref { visible_name: name, def: Definition::from(def) })
-            }
+            ScopeDef::ModuleDef(def) => Some(Ref {
+                visible_name: name,
+                def: Definition::from(def),
+                is_pub: matches!(def.visibility(ctx.db()), hir::Visibility::Public),
+            }),
             _ => None,
         }
     }
@@ -180,32 +298,32 @@ fn find_refs_in_mod(
     ctx: &AssistContext<'_>,
     expandable: Expandable,
     visible_from: Module,
-) -> Option<Refs> {
-    if !is_expandable_visible_from(ctx, &expandable, visible_from) {
-        return None;
-    }
-
+    must_be_pub: bool,
+) -> Refs {
     match expandable {
         Expandable::Module(module) => {
             let module_scope = module.scope(ctx.db(), Some(visible_from));
-            let refs =
-                module_scope.into_iter().filter_map(|(n, d)| Ref::from_scope_def(n, d)).collect();
-            Some(Refs(refs))
+            let refs = module_scope
+                .into_iter()
+                .filter_map(|(n, d)| Ref::from_scope_def(ctx, n, d))
+                .filter(|r| !must_be_pub || r.is_pub)
+                .collect();
+            Refs(refs)
         }
-        Expandable::Enum(enm) => Some(Refs(
+        Expandable::Enum(enm) => Refs(
             enm.variants(ctx.db())
                 .into_iter()
-                .map(|v| Ref { visible_name: v.name(ctx.db()), def: Definition::Variant(v) })
+                .map(|v| Ref {
+                    visible_name: v.name(ctx.db()),
+                    def: Definition::Variant(v),
+                    is_pub: true,
+                })
                 .collect(),
-        )),
+        ),
     }
 }
 
-fn is_expandable_visible_from(
-    ctx: &AssistContext<'_>,
-    expandable: &Expandable,
-    from: Module,
-) -> bool {
+fn is_visible_from(ctx: &AssistContext<'_>, expandable: &Expandable, from: Module) -> bool {
     fn is_mod_visible_from(ctx: &AssistContext<'_>, module: Module, from: Module) -> bool {
         match module.parent(ctx.db()) {
             Some(parent) => {
@@ -246,50 +364,34 @@ fn is_expandable_visible_from(
 // use foo::*$0;
 // use baz::Baz;
 // ↑ ---------------
-fn find_imported_defs(ctx: &AssistContext<'_>, star: SyntaxToken) -> Option<Vec<Definition>> {
-    let parent_use_item_syntax = star.parent_ancestors().find_map(|n| {
-        if ast::Use::can_cast(n.kind()) {
-            Some(n)
-        } else {
-            None
-        }
-    })?;
-
-    Some(
-        [Direction::Prev, Direction::Next]
-            .into_iter()
-            .flat_map(|dir| {
-                parent_use_item_syntax
-                    .siblings(dir.to_owned())
-                    .filter(|n| ast::Use::can_cast(n.kind()))
-            })
-            .flat_map(|n| n.descendants().filter_map(ast::NameRef::cast))
-            .filter_map(|r| match NameRefClass::classify(&ctx.sema, &r)? {
-                NameRefClass::Definition(
-                    def @ (Definition::Macro(_)
-                    | Definition::Module(_)
-                    | Definition::Function(_)
-                    | Definition::Adt(_)
-                    | Definition::Variant(_)
-                    | Definition::Const(_)
-                    | Definition::Static(_)
-                    | Definition::Trait(_)
-                    | Definition::TypeAlias(_)),
-                    _,
-                ) => Some(def),
-                _ => None,
-            })
-            .collect(),
-    )
+fn find_imported_defs(ctx: &AssistContext<'_>, use_item: Use) -> Vec<Definition> {
+    [Direction::Prev, Direction::Next]
+        .into_iter()
+        .flat_map(|dir| {
+            use_item.syntax().siblings(dir.to_owned()).filter(|n| ast::Use::can_cast(n.kind()))
+        })
+        .flat_map(|n| n.descendants().filter_map(ast::NameRef::cast))
+        .filter_map(|r| match NameRefClass::classify(&ctx.sema, &r)? {
+            NameRefClass::Definition(
+                def @ (Definition::Macro(_)
+                | Definition::Module(_)
+                | Definition::Function(_)
+                | Definition::Adt(_)
+                | Definition::Variant(_)
+                | Definition::Const(_)
+                | Definition::Static(_)
+                | Definition::Trait(_)
+                | Definition::TypeAlias(_)),
+                _,
+            ) => Some(def),
+            _ => None,
+        })
+        .collect()
 }
 
-fn find_names_to_import(
-    ctx: &AssistContext<'_>,
-    refs_in_target: Refs,
-    imported_defs: Vec<Definition>,
-) -> Vec<Name> {
-    let used_refs = refs_in_target.used_refs(ctx).filter_out_by_defs(imported_defs);
-    used_refs.0.iter().map(|r| r.visible_name.clone()).collect()
+fn find_names_to_import(refs_in_target: Refs, imported_defs: Vec<Definition>) -> Vec<Name> {
+    let final_refs = refs_in_target.filter_out_by_defs(imported_defs);
+    final_refs.0.iter().map(|r| r.visible_name.clone()).collect()
 }
 
 #[cfg(test)]
@@ -1036,4 +1138,83 @@ mod abc {
 }"#,
         )
     }
+
+    #[test]
+    fn expanding_glob_reexport() {
+        check_assist(
+            expand_glob_reexport,
+            r"
+mod foo {
+    pub struct Bar;
+    pub struct Baz;
+    struct Qux;
+
+    pub fn f() {}
+
+    pub(crate) fn g() {}
+    pub(self) fn h() {}
+}
+
+pub use foo::*$0;
+",
+            r"
+mod foo {
+    pub struct Bar;
+    pub struct Baz;
+    struct Qux;
+
+    pub fn f() {}
+
+    pub(crate) fn g() {}
+    pub(self) fn h() {}
+}
+
+pub use foo::{Bar, Baz, f};
+",
+        )
+    }
+
+    #[test]
+    fn expanding_recursive_glob_reexport() {
+        check_assist(
+            expand_glob_reexport,
+            r"
+mod foo {
+    pub use bar::*;
+    mod bar {
+        pub struct Bar;
+        pub struct Baz;
+    }
+}
+
+pub use foo::*$0;
+",
+            r"
+mod foo {
+    pub use bar::*;
+    mod bar {
+        pub struct Bar;
+        pub struct Baz;
+    }
+}
+
+pub use foo::{Bar, Baz};
+",
+        )
+    }
+
+    #[test]
+    fn expanding_reexport_is_not_applicable_for_private_import() {
+        check_assist_not_applicable(
+            expand_glob_reexport,
+            r"
+mod foo {
+    pub struct Bar;
+    pub struct Baz;
+}
+
+use foo::*$0;
+",
+        );
+    }
 }
diff --git a/crates/ide-assists/src/lib.rs b/crates/ide-assists/src/lib.rs
index 5c95b25f28..179742f91b 100644
--- a/crates/ide-assists/src/lib.rs
+++ b/crates/ide-assists/src/lib.rs
@@ -270,6 +270,7 @@ mod handlers {
             destructure_tuple_binding::destructure_tuple_binding,
             destructure_struct_binding::destructure_struct_binding,
             expand_glob_import::expand_glob_import,
+            expand_glob_import::expand_glob_reexport,
             explicit_enum_discriminant::explicit_enum_discriminant,
             extract_expressions_from_format_string::extract_expressions_from_format_string,
             extract_struct_from_enum_variant::extract_struct_from_enum_variant,


Test patch:
diff --git a/crates/ide-assists/src/tests/generated.rs b/crates/ide-assists/src/tests/generated.rs
index 4b0fa704a2..0662527a38 100644
--- a/crates/ide-assists/src/tests/generated.rs
+++ b/crates/ide-assists/src/tests/generated.rs
@@ -909,6 +909,29 @@ fn qux(bar: Bar, baz: Baz) {}
     )
 }
 
+#[test]
+fn doctest_expand_glob_reexport() {
+    check_doc_test(
+        "expand_glob_reexport",
+        r#####"
+mod foo {
+    pub struct Bar;
+    pub struct Baz;
+}
+
+pub use foo::*$0;
+"#####,
+        r#####"
+mod foo {
+    pub struct Bar;
+    pub struct Baz;
+}
+
+pub use foo::{Bar, Baz};
+"#####,
+    )
+}
+
 #[test]
 fn doctest_explicit_enum_discriminant() {
     check_doc_test(