8 files changed, 200 insertions, 105 deletions

diff --git a/crates/assists/src/handlers/generate_from_impl_for_enum.rs b/crates/assists/src/handlers/generate_from_impl_for_enum.rs
index d9af6ab11..d9388a737 100644
--- a/crates/assists/src/handlers/generate_from_impl_for_enum.rs
+++ b/crates/assists/src/handlers/generate_from_impl_for_enum.rs
@@ -3,7 +3,7 @@ use ide_db::RootDatabase;
 use syntax::ast::{self, AstNode, NameOwner};
 use test_utils::mark;
 
-use crate::{AssistContext, AssistId, AssistKind, Assists};
+use crate::{utils::generate_trait_impl_text, AssistContext, AssistId, AssistKind, Assists};
 
 // Assist: generate_from_impl_for_enum
 //
@@ -18,25 +18,29 @@ use crate::{AssistContext, AssistId, AssistKind, Assists};
 //
 // impl From<u32> for A {
 //     fn from(v: u32) -> Self {
-//         A::One(v)
+//         Self::One(v)
 //     }
 // }
 // ```
 pub(crate) fn generate_from_impl_for_enum(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
     let variant = ctx.find_node_at_offset::<ast::Variant>()?;
     let variant_name = variant.name()?;
-    let enum_name = variant.parent_enum().name()?;
-    let field_list = match variant.kind() {
-        ast::StructKind::Tuple(field_list) => field_list,
-        _ => return None,
-    };
-    if field_list.fields().count() != 1 {
-        return None;
-    }
-    let field_type = field_list.fields().next()?.ty()?;
-    let path = match field_type {
-        ast::Type::PathType(it) => it,
-        _ => return None,
+    let enum_ = ast::Adt::Enum(variant.parent_enum());
+    let (field_name, field_type) = match variant.kind() {
+        ast::StructKind::Tuple(field_list) => {
+            if field_list.fields().count() != 1 {
+                return None;
+            }
+            (None, field_list.fields().next()?.ty()?)
+        }
+        ast::StructKind::Record(field_list) => {
+            if field_list.fields().count() != 1 {
+                return None;
+            }
+            let field = field_list.fields().next()?;
+            (Some(field.name()?), field.ty()?)
+        }
+        ast::StructKind::Unit => return None,
     };
 
     if existing_from_impl(&ctx.sema, &variant).is_some() {
@@ -51,19 +55,27 @@ pub(crate) fn generate_from_impl_for_enum(acc: &mut Assists, ctx: &AssistContext
         target,
         |edit| {
             let start_offset = variant.parent_enum().syntax().text_range().end();
-            let buf = format!(
-                r#"
-
-impl From<{0}> for {1} {{
-    fn from(v: {0}) -> Self {{
-        {1}::{2}(v)
-    }}
-}}"#,
-                path.syntax(),
-                enum_name,
-                variant_name
-            );
-            edit.insert(start_offset, buf);
+            let from_trait = format!("From<{}>", field_type.syntax());
+            let impl_code = if let Some(name) = field_name {
+                format!(
+                    r#"    fn from({0}: {1}) -> Self {{
+        Self::{2} {{ {0} }}
+    }}"#,
+                    name.text(),
+                    field_type.syntax(),
+                    variant_name,
+                )
+            } else {
+                format!(
+                    r#"    fn from(v: {}) -> Self {{
+        Self::{}(v)
+    }}"#,
+                    field_type.syntax(),
+                    variant_name,
+                )
+            };
+            let from_impl = generate_trait_impl_text(&enum_, &from_trait, &impl_code);
+            edit.insert(start_offset, from_impl);
         },
     )
 }
@@ -106,7 +118,7 @@ mod tests {
 
 impl From<u32> for A {
     fn from(v: u32) -> Self {
-        A::One(v)
+        Self::One(v)
     }
 }"#,
         );
@@ -121,7 +133,7 @@ impl From<u32> for A {
 
 impl From<foo::bar::baz::Boo> for A {
     fn from(v: foo::bar::baz::Boo) -> Self {
-        A::One(v)
+        Self::One(v)
     }
 }"#,
         );
@@ -145,7 +157,17 @@ impl From<foo::bar::baz::Boo> for A {
 
     #[test]
     fn test_add_from_impl_struct_variant() {
-        check_not_applicable("enum A { $0One { x: u32 } }");
+        check_assist(
+            generate_from_impl_for_enum,
+            "enum A { $0One { x: u32 } }",
+            r#"enum A { One { x: u32 } }
+
+impl From<u32> for A {
+    fn from(x: u32) -> Self {
+        Self::One { x }
+    }
+}"#,
+        );
     }
 
     #[test]
@@ -157,7 +179,7 @@ enum A { $0One(u32), }
 
 impl From<u32> for A {
     fn from(v: u32) -> Self {
-        A::One(v)
+        Self::One(v)
     }
 }
 "#,
@@ -183,7 +205,7 @@ pub trait From<T> {
 
 impl From<u32> for A {
     fn from(v: u32) -> Self {
-        A::One(v)
+        Self::One(v)
     }
 }
 
@@ -198,4 +220,49 @@ pub trait From<T> {
 }"#,
         );
     }
+
+    #[test]
+    fn test_add_from_impl_static_str() {
+        check_assist(
+            generate_from_impl_for_enum,
+            "enum A { $0One(&'static str) }",
+            r#"enum A { One(&'static str) }
+
+impl From<&'static str> for A {
+    fn from(v: &'static str) -> Self {
+        Self::One(v)
+    }
+}"#,
+        );
+    }
+
+    #[test]
+    fn test_add_from_impl_generic_enum() {
+        check_assist(
+            generate_from_impl_for_enum,
+            "enum Generic<T, U: Clone> { $0One(T), Two(U) }",
+            r#"enum Generic<T, U: Clone> { One(T), Two(U) }
+
+impl<T, U: Clone> From<T> for Generic<T, U> {
+    fn from(v: T) -> Self {
+        Self::One(v)
+    }
+}"#,
+        );
+    }
+
+    #[test]
+    fn test_add_from_impl_with_lifetime() {
+        check_assist(
+            generate_from_impl_for_enum,
+            "enum Generic<'a> { $0One(&'a i32) }",
+            r#"enum Generic<'a> { One(&'a i32) }
+
+impl<'a> From<&'a i32> for Generic<'a> {
+    fn from(v: &'a i32) -> Self {
+        Self::One(v)
+    }
+}"#,
+        );
+    }
 }
diff --git a/crates/assists/src/handlers/generate_getter.rs b/crates/assists/src/handlers/generate_getter.rs
index fbcf8b069..df7d1bb95 100644
--- a/crates/assists/src/handlers/generate_getter.rs
+++ b/crates/assists/src/handlers/generate_getter.rs
@@ -1,10 +1,9 @@
 use stdx::{format_to, to_lower_snake_case};
-use syntax::ast::VisibilityOwner;
-use syntax::ast::{self, AstNode, NameOwner};
+use syntax::ast::{self, AstNode, NameOwner, VisibilityOwner};
 
 use crate::{
     utils::{find_impl_block_end, find_struct_impl, generate_impl_text},
-    AssistContext, AssistId, AssistKind, Assists,
+    AssistContext, AssistId, AssistKind, Assists, GroupLabel,
 };
 
 // Assist: generate_getter
@@ -42,7 +41,8 @@ pub(crate) fn generate_getter(acc: &mut Assists, ctx: &AssistContext) -> Option<
     let impl_def = find_struct_impl(&ctx, &ast::Adt::Struct(strukt.clone()), fn_name.as_str())?;
 
     let target = field.syntax().text_range();
-    acc.add(
+    acc.add_group(
+        &GroupLabel("Generate getter/setter".to_owned()),
         AssistId("generate_getter", AssistKind::Generate),
         "Generate a getter method",
         target,
diff --git a/crates/assists/src/handlers/generate_getter_mut.rs b/crates/assists/src/handlers/generate_getter_mut.rs
index bf0d99881..821c2eed5 100644
--- a/crates/assists/src/handlers/generate_getter_mut.rs
+++ b/crates/assists/src/handlers/generate_getter_mut.rs
@@ -1,10 +1,9 @@
 use stdx::{format_to, to_lower_snake_case};
-use syntax::ast::VisibilityOwner;
-use syntax::ast::{self, AstNode, NameOwner};
+use syntax::ast::{self, AstNode, NameOwner, VisibilityOwner};
 
 use crate::{
     utils::{find_impl_block_end, find_struct_impl, generate_impl_text},
-    AssistContext, AssistId, AssistKind, Assists,
+    AssistContext, AssistId, AssistKind, Assists, GroupLabel,
 };
 
 // Assist: generate_getter_mut
@@ -46,7 +45,8 @@ pub(crate) fn generate_getter_mut(acc: &mut Assists, ctx: &AssistContext) -> Opt
     )?;
 
     let target = field.syntax().text_range();
-    acc.add(
+    acc.add_group(
+        &GroupLabel("Generate getter/setter".to_owned()),
         AssistId("generate_getter_mut", AssistKind::Generate),
         "Generate a mut getter method",
         target,
diff --git a/crates/assists/src/handlers/generate_impl.rs b/crates/assists/src/handlers/generate_impl.rs
index 61d1bd25c..16a600e6f 100644
--- a/crates/assists/src/handlers/generate_impl.rs
+++ b/crates/assists/src/handlers/generate_impl.rs
@@ -1,11 +1,6 @@
-use itertools::Itertools;
-use stdx::format_to;
-use syntax::{
-    ast::{self, AstNode, AttrsOwner, GenericParamsOwner, NameOwner},
-    SmolStr,
-};
+use syntax::ast::{self, AstNode, NameOwner};
 
-use crate::{AssistContext, AssistId, AssistKind, Assists};
+use crate::{utils::generate_impl_text, AssistContext, AssistId, AssistKind, Assists};
 
 // Assist: generate_impl
 //
@@ -36,44 +31,15 @@ pub(crate) fn generate_impl(acc: &mut Assists, ctx: &AssistContext) -> Option<()
         format!("Generate impl for `{}`", name),
         target,
         |edit| {
-            let type_params = nominal.generic_param_list();
             let start_offset = nominal.syntax().text_range().end();
-            let mut buf = String::new();
-            buf.push_str("\n\n");
-            nominal
-                .attrs()
-                .filter(|attr| {
-                    attr.as_simple_call().map(|(name, _arg)| name == "cfg").unwrap_or(false)
-                })
-                .for_each(|attr| buf.push_str(format!("{}\n", attr.to_string()).as_str()));
-
-            buf.push_str("impl");
-            if let Some(type_params) = &type_params {
-                format_to!(buf, "{}", type_params.syntax());
-            }
-            buf.push_str(" ");
-            buf.push_str(name.text());
-            if let Some(type_params) = type_params {
-                let lifetime_params = type_params
-                    .lifetime_params()
-                    .filter_map(|it| it.lifetime())
-                    .map(|it| SmolStr::from(it.text()));
-                let type_params = type_params
-                    .type_params()
-                    .filter_map(|it| it.name())
-                    .map(|it| SmolStr::from(it.text()));
-
-                let generic_params = lifetime_params.chain(type_params).format(", ");
-                format_to!(buf, "<{}>", generic_params)
-            }
             match ctx.config.snippet_cap {
                 Some(cap) => {
-                    buf.push_str(" {\n    $0\n}");
-                    edit.insert_snippet(cap, start_offset, buf);
+                    let snippet = generate_impl_text(&nominal, "    $0");
+                    edit.insert_snippet(cap, start_offset, snippet);
                 }
                 None => {
-                    buf.push_str(" {\n}");
-                    edit.insert(start_offset, buf);
+                    let snippet = generate_impl_text(&nominal, "");
+                    edit.insert(start_offset, snippet);
                 }
             }
         },
@@ -132,6 +98,30 @@ mod tests {
                 $0
             }"#,
         );
+
+        check_assist(
+            generate_impl,
+            r#"
+            struct Defaulted<T = i32> {}$0"#,
+            r#"
+            struct Defaulted<T = i32> {}
+
+            impl<T> Defaulted<T> {
+                $0
+            }"#,
+        );
+
+        check_assist(
+            generate_impl,
+            r#"
+            struct Defaulted<'a, 'b: 'a, T: Debug + Clone + 'a + 'b = String> {}$0"#,
+            r#"
+            struct Defaulted<'a, 'b: 'a, T: Debug + Clone + 'a + 'b = String> {}
+
+            impl<'a, 'b: 'a, T: Debug + Clone + 'a + 'b> Defaulted<'a, 'b, T> {
+                $0
+            }"#,
+        );
     }
 
     #[test]
diff --git a/crates/assists/src/handlers/generate_setter.rs b/crates/assists/src/handlers/generate_setter.rs
index b655f9b9c..288cf745d 100644
--- a/crates/assists/src/handlers/generate_setter.rs
+++ b/crates/assists/src/handlers/generate_setter.rs
@@ -1,10 +1,9 @@
 use stdx::{format_to, to_lower_snake_case};
-use syntax::ast::VisibilityOwner;
-use syntax::ast::{self, AstNode, NameOwner};
+use syntax::ast::{self, AstNode, NameOwner, VisibilityOwner};
 
 use crate::{
     utils::{find_impl_block_end, find_struct_impl, generate_impl_text},
-    AssistContext, AssistId, AssistKind, Assists,
+    AssistContext, AssistId, AssistKind, Assists, GroupLabel,
 };
 
 // Assist: generate_setter
@@ -46,7 +45,8 @@ pub(crate) fn generate_setter(acc: &mut Assists, ctx: &AssistContext) -> Option<
     )?;
 
     let target = field.syntax().text_range();
-    acc.add(
+    acc.add_group(
+        &GroupLabel("Generate getter/setter".to_owned()),
         AssistId("generate_setter", AssistKind::Generate),
         "Generate a setter method",
         target,
diff --git a/crates/assists/src/handlers/replace_derive_with_manual_impl.rs b/crates/assists/src/handlers/replace_derive_with_manual_impl.rs
index 6aa9d2f2c..c69bc5cac 100644
--- a/crates/assists/src/handlers/replace_derive_with_manual_impl.rs
+++ b/crates/assists/src/handlers/replace_derive_with_manual_impl.rs
@@ -2,8 +2,7 @@ use ide_db::helpers::mod_path_to_ast;
 use ide_db::imports_locator;
 use itertools::Itertools;
 use syntax::{
-    ast::{self, make, AstNode},
-    Direction,
+    ast::{self, make, AstNode, NameOwner},
     SyntaxKind::{IDENT, WHITESPACE},
     TextSize,
 };
@@ -11,7 +10,8 @@ use syntax::{
 use crate::{
     assist_context::{AssistBuilder, AssistContext, Assists},
     utils::{
-        add_trait_assoc_items_to_impl, filter_assoc_items, render_snippet, Cursor, DefaultMethods,
+        add_trait_assoc_items_to_impl, filter_assoc_items, generate_trait_impl_text,
+        render_snippet, Cursor, DefaultMethods,
     },
     AssistId, AssistKind,
 };
@@ -57,8 +57,9 @@ pub(crate) fn replace_derive_with_manual_impl(
     let trait_token = ctx.token_at_offset().find(|t| t.kind() == IDENT && t.text() != "derive")?;
     let trait_path = make::path_unqualified(make::path_segment(make::name_ref(trait_token.text())));
 
-    let annotated_name = attr.syntax().siblings(Direction::Next).find_map(ast::Name::cast)?;
-    let insert_pos = annotated_name.syntax().parent()?.text_range().end();
+    let adt = attr.syntax().parent().and_then(ast::Adt::cast)?;
+    let annotated_name = adt.name()?;
+    let insert_pos = adt.syntax().text_range().end();
 
     let current_module = ctx.sema.scope(annotated_name.syntax()).module()?;
     let current_crate = current_module.krate();
@@ -82,10 +83,10 @@ pub(crate) fn replace_derive_with_manual_impl(
 
     let mut no_traits_found = true;
     for (trait_path, trait_) in found_traits.inspect(|_| no_traits_found = false) {
-        add_assist(acc, ctx, &attr, &trait_path, Some(trait_), &annotated_name, insert_pos)?;
+        add_assist(acc, ctx, &attr, &trait_path, Some(trait_), &adt, &annotated_name, insert_pos)?;
     }
     if no_traits_found {
-        add_assist(acc, ctx, &attr, &trait_path, None, &annotated_name, insert_pos)?;
+        add_assist(acc, ctx, &attr, &trait_path, None, &adt, &annotated_name, insert_pos)?;
     }
     Some(())
 }
@@ -96,6 +97,7 @@ fn add_assist(
     attr: &ast::Attr,
     trait_path: &ast::Path,
     trait_: Option<hir::Trait>,
+    adt: &ast::Adt,
     annotated_name: &ast::Name,
     insert_pos: TextSize,
 ) -> Option<()> {
@@ -112,15 +114,15 @@ fn add_assist(
             let impl_def_with_items =
                 impl_def_from_trait(&ctx.sema, annotated_name, trait_, trait_path);
             update_attribute(builder, &input, &trait_name, &attr);
+            let trait_path = format!("{}", trait_path);
             match (ctx.config.snippet_cap, impl_def_with_items) {
-                (None, _) => builder.insert(
-                    insert_pos,
-                    format!("\n\nimpl {} for {} {{\n\n}}", trait_path, annotated_name),
-                ),
+                (None, _) => {
+                    builder.insert(insert_pos, generate_trait_impl_text(adt, &trait_path, ""))
+                }
                 (Some(cap), None) => builder.insert_snippet(
                     cap,
                     insert_pos,
-                    format!("\n\nimpl {} for {} {{\n    $0\n}}", trait_path, annotated_name),
+                    generate_trait_impl_text(adt, &trait_path, "    $0"),
                 ),
                 (Some(cap), Some((impl_def, first_assoc_item))) => {
                     let mut cursor = Cursor::Before(first_assoc_item.syntax());
diff --git a/crates/assists/src/tests/generated.rs b/crates/assists/src/tests/generated.rs
index 6f2b22bc2..0516deaff 100644
--- a/crates/assists/src/tests/generated.rs
+++ b/crates/assists/src/tests/generated.rs
@@ -499,7 +499,7 @@ enum A { One(u32) }
 
 impl From<u32> for A {
     fn from(v: u32) -> Self {
-        A::One(v)
+        Self::One(v)
     }
 }
 "#####,
diff --git a/crates/assists/src/utils.rs b/crates/assists/src/utils.rs
index 5dd32aef1..8418e6e12 100644
--- a/crates/assists/src/utils.rs
+++ b/crates/assists/src/utils.rs
@@ -2,6 +2,7 @@
 
 use std::ops;
 
+use ast::TypeBoundsOwner;
 use hir::{Adt, HasSource};
 use ide_db::{helpers::SnippetCap, RootDatabase};
 use itertools::Itertools;
@@ -367,21 +368,56 @@ pub(crate) fn find_impl_block_end(impl_def: ast::Impl, buf: &mut String) -> Opti
 // Generates the surrounding `impl Type { <code> }` including type and lifetime
 // parameters
 pub(crate) fn generate_impl_text(adt: &ast::Adt, code: &str) -> String {
-    let type_params = adt.generic_param_list();
+    generate_impl_text_inner(adt, None, code)
+}
+
+// Generates the surrounding `impl <trait> for Type { <code> }` including type
+// and lifetime parameters
+pub(crate) fn generate_trait_impl_text(adt: &ast::Adt, trait_text: &str, code: &str) -> String {
+    generate_impl_text_inner(adt, Some(trait_text), code)
+}
+
+fn generate_impl_text_inner(adt: &ast::Adt, trait_text: Option<&str>, code: &str) -> String {
+    let generic_params = adt.generic_param_list();
     let mut buf = String::with_capacity(code.len());
-    buf.push_str("\n\nimpl");
-    if let Some(type_params) = &type_params {
-        format_to!(buf, "{}", type_params.syntax());
+    buf.push_str("\n\n");
+    adt.attrs()
+        .filter(|attr| attr.as_simple_call().map(|(name, _arg)| name == "cfg").unwrap_or(false))
+        .for_each(|attr| buf.push_str(format!("{}\n", attr.to_string()).as_str()));
+    buf.push_str("impl");
+    if let Some(generic_params) = &generic_params {
+        let lifetimes = generic_params.lifetime_params().map(|lt| format!("{}", lt.syntax()));
+        let type_params = generic_params.type_params().map(|type_param| {
+            let mut buf = String::new();
+            if let Some(it) = type_param.name() {
+                format_to!(buf, "{}", it.syntax());
+            }
+            if let Some(it) = type_param.colon_token() {
+                format_to!(buf, "{} ", it);
+            }
+            if let Some(it) = type_param.type_bound_list() {
+                format_to!(buf, "{}", it.syntax());
+            }
+            buf
+        });
+        let generics = lifetimes.chain(type_params).format(", ");
+        format_to!(buf, "<{}>", generics);
     }
     buf.push(' ');
+    if let Some(trait_text) = trait_text {
+        buf.push_str(trait_text);
+        buf.push_str(" for ");
+    }
     buf.push_str(adt.name().unwrap().text());
-    if let Some(type_params) = type_params {
-        let lifetime_params = type_params
+    if let Some(generic_params) = generic_params {
+        let lifetime_params = generic_params
             .lifetime_params()
             .filter_map(|it| it.lifetime())
             .map(|it| SmolStr::from(it.text()));
-        let type_params =
-            type_params.type_params().filter_map(|it| it.name()).map(|it| SmolStr::from(it.text()));
+        let type_params = generic_params
+            .type_params()
+            .filter_map(|it| it.name())
+            .map(|it| SmolStr::from(it.text()));
         format_to!(buf, "<{}>", lifetime_params.chain(type_params).format(", "))
     }