1 files changed, 13 insertions, 25 deletions

diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_type_alias.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_type_alias.rs
index 03aa8601d..3116935fc 100644
--- a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_type_alias.rs
+++ b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_type_alias.rs
@@ -1,8 +1,7 @@
 use either::Either;
 use ide_db::syntax_helpers::node_ext::walk_ty;
-use itertools::Itertools;
 use syntax::{
-    ast::{self, edit::IndentLevel, AstNode, HasGenericParams, HasName},
+    ast::{self, edit::IndentLevel, make, AstNode, HasGenericParams, HasName},
     match_ast,
 };
 
@@ -64,41 +63,29 @@ pub(crate) fn extract_type_alias(acc: &mut Assists, ctx: &AssistContext<'_>) ->
                 known_generics.extend(it.generic_params());
             }
             let generics = collect_used_generics(&ty, &known_generics);
+            let generic_params =
+                generics.map(|it| make::generic_param_list(it.into_iter().cloned()));
 
-            let replacement = if !generics.is_empty() {
-                format!(
-                    "Type<{}>",
-                    generics.iter().format_with(", ", |generic, f| {
-                        match generic {
-                            ast::GenericParam::ConstParam(cp) => f(&cp.name().unwrap()),
-                            ast::GenericParam::LifetimeParam(lp) => f(&lp.lifetime().unwrap()),
-                            ast::GenericParam::TypeParam(tp) => f(&tp.name().unwrap()),
-                        }
-                    })
-                )
-            } else {
-                String::from("Type")
-            };
+            let ty_args = generic_params
+                .as_ref()
+                .map_or(String::new(), |it| it.to_generic_args().to_string());
+            let replacement = format!("Type{ty_args}");
             builder.replace(target, replacement);
 
             let indent = IndentLevel::from_node(node);
-            let generics = if !generics.is_empty() {
-                format!("<{}>", generics.iter().format(", "))
-            } else {
-                String::new()
-            };
+            let generic_params = generic_params.map_or(String::new(), |it| it.to_string());
             match ctx.config.snippet_cap {
                 Some(cap) => {
                     builder.insert_snippet(
                         cap,
                         insert_pos,
-                        format!("type $0Type{} = {};\n\n{}", generics, ty, indent),
+                        format!("type $0Type{generic_params} = {ty};\n\n{indent}"),
                     );
                 }
                 None => {
                     builder.insert(
                         insert_pos,
-                        format!("type Type{} = {};\n\n{}", generics, ty, indent),
+                        format!("type Type{generic_params} = {ty};\n\n{indent}"),
                     );
                 }
             }
@@ -109,7 +96,7 @@ pub(crate) fn extract_type_alias(acc: &mut Assists, ctx: &AssistContext<'_>) ->
 fn collect_used_generics<'gp>(
     ty: &ast::Type,
     known_generics: &'gp [ast::GenericParam],
-) -> Vec<&'gp ast::GenericParam> {
+) -> Option<Vec<&'gp ast::GenericParam>> {
     // can't use a closure -> closure here cause lifetime inference fails for that
     fn find_lifetime(text: &str) -> impl Fn(&&ast::GenericParam) -> bool + '_ {
         move |gp: &&ast::GenericParam| match gp {
@@ -198,7 +185,8 @@ fn collect_used_generics<'gp>(
         ast::GenericParam::LifetimeParam(_) => 0,
         ast::GenericParam::TypeParam(_) => 1,
     });
-    generics
+
+    Some(generics).filter(|it| it.len() > 0)
 }
 
 #[cfg(test)]