Use mutable syntax trees in `merge_imports`, `split_imports`

[rust.git] / crates / ide_assists / src / handlers / replace_qualified_name_with_use.rs

diff --git a/crates/ide_assists/src/handlers/replace_qualified_name_with_use.rs b/crates/ide_assists/src/handlers/replace_qualified_name_with_use.rs
index 7aad4a44b6af6ab6906d960d8d0e0ae3457b3e1d..6b196681cab0936d2e0491803fa111ad75e30df8 100644 (file)
--- a/crates/ide_assists/src/handlers/replace_qualified_name_with_use.rs
+++ b/crates/ide_assists/src/handlers/replace_qualified_name_with_use.rs
@@ -3,7 +3,10 @@
     insert_use::{insert_use, ImportScope},
     mod_path_to_ast,
 };
-use syntax::{ast, match_ast, ted, AstNode, SyntaxNode};
+use syntax::{
+    ast::{self, make},
+    match_ast, ted, AstNode, SyntaxNode,
+};
 
 use crate::{AssistContext, AssistId, AssistKind, Assists};
 
@@ -38,20 +41,37 @@ pub(crate) fn replace_qualified_name_with_use(
         return None;
     }
 
-    let res = ctx.sema.resolve_path(&path)?;
-    let def: hir::ItemInNs = match res {
-        hir::PathResolution::Def(def) if def.as_assoc_item(ctx.sema.db).is_none() => def.into(),
-        hir::PathResolution::Macro(mac) => mac.into(),
+    // only offer replacement for non assoc items
+    match ctx.sema.resolve_path(&path)? {
+        hir::PathResolution::Def(def) if def.as_assoc_item(ctx.sema.db).is_none() => (),
+        hir::PathResolution::Macro(_) => (),
+        _ => return None,
+    }
+    // then search for an import for the first path segment of what we want to replace
+    // that way it is less likely that we import the item from a different location due re-exports
+    let module = match ctx.sema.resolve_path(&path.first_qualifier_or_self())? {
+        hir::PathResolution::Def(module @ hir::ModuleDef::Module(_)) => module,
         _ => return None,
     };
 
+    let starts_with_name_ref = !matches!(
+        path.first_segment().and_then(|it| it.kind()),
+        Some(
+            ast::PathSegmentKind::CrateKw
+                | ast::PathSegmentKind::SuperKw
+                | ast::PathSegmentKind::SelfKw
+        )
+    );
+    let path_to_qualifier = starts_with_name_ref
+        .then(|| {
+            ctx.sema.scope(path.syntax()).module().and_then(|m| {
+                m.find_use_path_prefixed(ctx.sema.db, module, ctx.config.insert_use.prefix_kind)
+            })
+        })
+        .flatten();
+
+    let scope = ImportScope::find_insert_use_container(path.syntax(), &ctx.sema)?;
     let target = path.syntax().text_range();
-    let scope = ImportScope::find_insert_use_container_with_macros(path.syntax(), &ctx.sema)?;
-    let mod_path = ctx.sema.scope(path.syntax()).module()?.find_use_path_prefixed(
-        ctx.sema.db,
-        def,
-        ctx.config.insert_use.prefix_kind,
-    )?;
     acc.add(
         AssistId("replace_qualified_name_with_use", AssistKind::RefactorRewrite),
         "Replace qualified path with use",
@@ -64,7 +84,11 @@ pub(crate) fn replace_qualified_name_with_use(
                 ImportScope::Module(it) => ImportScope::Module(builder.make_mut(it)),
                 ImportScope::Block(it) => ImportScope::Block(builder.make_mut(it)),
             };
-            let path = mod_path_to_ast(&mod_path);
+            // stick the found import in front of the to be replaced path
+            let path = match path_to_qualifier.and_then(|it| mod_path_to_ast(&it).qualifier()) {
+                Some(qualifier) => make::path_concat(qualifier, path),
+                None => path,
+            };
             shorten_paths(scope.as_syntax_node(), &path.clone_for_update());
             insert_use(&scope, path, &ctx.config.insert_use);
         },
@@ -117,10 +141,7 @@ fn path_eq_no_generics(lhs: ast::Path, rhs: ast::Path) -> bool {
                     && lhs
                         .name_ref()
                         .zip(rhs.name_ref())
-                        .map_or(false, |(lhs, rhs)| lhs.text() == rhs.text()) =>
-            {
-                ()
-            }
+                        .map_or(false, |(lhs, rhs)| lhs.text() == rhs.text()) => {}
             _ => return false,
         }
 
@@ -278,7 +299,7 @@ fn main() {
     ",
             r"
 mod std { pub mod fmt { pub trait Display {} } }
-use std::fmt::{self, Display};
+use std::fmt::{Display, self};
 
 fn main() {
     fmt;
@@ -300,6 +321,41 @@ pub fn foo() {}
 fn main() {
     Foo::foo$0();
 }
+",
+        );
+    }
+
+    #[test]
+    fn replace_reuses_path_qualifier() {
+        check_assist(
+            replace_qualified_name_with_use,
+            r"
+pub mod foo {
+    pub struct Foo;
+}
+
+mod bar {
+    pub use super::foo::Foo as Bar;
+}
+
+fn main() {
+    foo::Foo$0;
+}
+",
+            r"
+use foo::Foo;
+
+pub mod foo {
+    pub struct Foo;
+}
+
+mod bar {
+    pub use super::foo::Foo as Bar;
+}
+
+fn main() {
+    Foo;
+}
 ",
         );
     }