10 files changed, 446 insertions, 194 deletions

diff --git a/crates/assists/src/handlers/extract_module_to_file.rs b/crates/assists/src/handlers/extract_module_to_file.rs
index 5fc190fa6..3e67fdca2 100644
--- a/crates/assists/src/handlers/extract_module_to_file.rs
+++ b/crates/assists/src/handlers/extract_module_to_file.rs
@@ -1,5 +1,5 @@
 use ast::edit::IndentLevel;
-use ide_db::base_db::{AnchoredPathBuf, SourceDatabaseExt};
+use ide_db::base_db::AnchoredPathBuf;
 use syntax::{
     ast::{self, edit::AstNodeEdit, NameOwner},
     AstNode,
@@ -21,43 +21,44 @@ use crate::{AssistContext, AssistId, AssistKind, Assists};
 // mod foo;
 // ```
 pub(crate) fn extract_module_to_file(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
-    let assist_id = AssistId("extract_module_to_file", AssistKind::RefactorExtract);
-    let assist_label = "Extract module to file";
-    let db = ctx.db();
     let module_ast = ctx.find_node_at_offset::<ast::Module>()?;
-    let module_items = module_ast.item_list()?;
-    let dedent_module_items_text = module_items.dedent(IndentLevel(1)).to_string();
     let module_name = module_ast.name()?;
+
+    let module_def = ctx.sema.to_def(&module_ast)?;
+    let parent_module = module_def.parent(ctx.db())?;
+
+    let module_items = module_ast.item_list()?;
     let target = module_ast.syntax().text_range();
     let anchor_file_id = ctx.frange.file_id;
-    let sr = db.file_source_root(anchor_file_id);
-    let sr = db.source_root(sr);
-    let file_path = sr.path_for_file(&anchor_file_id)?;
-    let (file_name, file_ext) = file_path.name_and_extension()?;
-    acc.add(assist_id, assist_label, target, |builder| {
-        builder.replace(target, format!("mod {};", module_name));
-        let path = if is_main_or_lib(file_name) {
-            format!("./{}.{}", module_name, file_ext.unwrap())
-        } else {
-            format!("./{}/{}.{}", file_name, module_name, file_ext.unwrap())
-        };
-        let dst = AnchoredPathBuf { anchor: anchor_file_id, path };
-        let contents = update_module_items_string(dedent_module_items_text);
-        builder.create_file(dst, contents);
-    })
-}
-fn is_main_or_lib(file_name: &str) -> bool {
-    file_name == "main".to_string() || file_name == "lib".to_string()
-}
-fn update_module_items_string(items_str: String) -> String {
-    let mut items_string_lines: Vec<&str> = items_str.lines().collect();
-    items_string_lines.pop(); // Delete last line
-    items_string_lines.reverse();
-    items_string_lines.pop(); // Delete first line
-    items_string_lines.reverse();
 
-    let string = items_string_lines.join("\n");
-    format!("{}", string)
+    acc.add(
+        AssistId("extract_module_to_file", AssistKind::RefactorExtract),
+        "Extract module to file",
+        target,
+        |builder| {
+            let path = {
+                let dir = match parent_module.name(ctx.db()) {
+                    Some(name) if !parent_module.is_mod_rs(ctx.db()) => format!("{}/", name),
+                    _ => String::new(),
+                };
+                format!("./{}{}.rs", dir, module_name)
+            };
+            let contents = {
+                let items = module_items.dedent(IndentLevel(1)).to_string();
+                let mut items =
+                    items.trim_start_matches('{').trim_end_matches('}').trim().to_string();
+                if !items.is_empty() {
+                    items.push('\n');
+                }
+                items
+            };
+
+            builder.replace(target, format!("mod {};", module_name));
+
+            let dst = AnchoredPathBuf { anchor: anchor_file_id, path };
+            builder.create_file(dst, contents);
+        },
+    )
 }
 
 #[cfg(test)]
@@ -67,104 +68,66 @@ mod tests {
     use super::*;
 
     #[test]
-    fn extract_module_to_file_with_basic_module() {
+    fn extract_from_root() {
         check_assist(
             extract_module_to_file,
             r#"
-//- /foo.rs crate:foo
 mod tests {<|>
     #[test] fn t() {}
 }
 "#,
             r#"
-//- /foo.rs
+//- /main.rs
 mod tests;
-//- /foo/tests.rs
-#[test] fn t() {}"#,
-        )
-    }
-
-    #[test]
-    fn extract_module_to_file_with_file_path() {
-        check_assist(
-            extract_module_to_file,
-            r#"
-//- /src/foo.rs crate:foo
-mod bar {<|>
-    fn f() {
-
-    }
-}
-fn main() {
-    println!("Hello, world!");
-}
+//- /tests.rs
+#[test] fn t() {}
 "#,
-            r#"
-//- /src/foo.rs
-mod bar;
-fn main() {
-    println!("Hello, world!");
-}
-//- /src/foo/bar.rs
-fn f() {
-
-}"#,
-        )
+        );
     }
 
     #[test]
-    fn extract_module_to_file_with_main_filw() {
+    fn extract_from_submodule() {
         check_assist(
             extract_module_to_file,
             r#"
 //- /main.rs
-mod foo {<|>
-    fn f() {
-
-    }
-}
-fn main() {
-    println!("Hello, world!");
+mod submodule;
+//- /submodule.rs
+mod inner<|> {
+    fn f() {}
 }
+fn g() {}
 "#,
             r#"
-//- /main.rs
-mod foo;
-fn main() {
-    println!("Hello, world!");
-}
-//- /foo.rs
-fn f() {
-
-}"#,
-        )
+//- /submodule.rs
+mod inner;
+fn g() {}
+//- /submodule/inner.rs
+fn f() {}
+"#,
+        );
     }
 
     #[test]
-    fn extract_module_to_file_with_lib_file() {
+    fn extract_from_mod_rs() {
         check_assist(
             extract_module_to_file,
             r#"
-//- /lib.rs
-mod foo {<|>
-    fn f() {
-
-    }
-}
-fn main() {
-    println!("Hello, world!");
+//- /main.rs
+mod submodule;
+//- /submodule/mod.rs
+mod inner<|> {
+    fn f() {}
 }
+fn g() {}
 "#,
             r#"
-//- /lib.rs
-mod foo;
-fn main() {
-    println!("Hello, world!");
-}
-//- /foo.rs
-fn f() {
-
-}"#,
-        )
+//- /submodule/mod.rs
+mod inner;
+fn g() {}
+//- /submodule/inner.rs
+fn f() {}
+"#,
+        );
     }
 }
diff --git a/crates/completion/src/completions.rs b/crates/completion/src/completions.rs
index 1ef6b5f48..d9fe13485 100644
--- a/crates/completion/src/completions.rs
+++ b/crates/completion/src/completions.rs
@@ -19,9 +19,14 @@ use hir::{ModPath, ScopeDef, Type};
 use crate::{
     item::Builder,
     render::{
-        const_::render_const, enum_variant::render_variant, function::render_fn,
-        macro_::render_macro, render_field, render_resolution, render_tuple_field,
-        type_alias::render_type_alias, RenderContext,
+        const_::render_const,
+        enum_variant::render_variant,
+        function::render_fn,
+        macro_::render_macro,
+        pattern::{render_struct_pat, render_variant_pat},
+        render_field, render_resolution, render_tuple_field,
+        type_alias::render_type_alias,
+        RenderContext,
     },
     CompletionContext, CompletionItem,
 };
@@ -105,6 +110,28 @@ impl Completions {
         self.add(item)
     }
 
+    pub(crate) fn add_variant_pat(
+        &mut self,
+        ctx: &CompletionContext,
+        variant: hir::Variant,
+        local_name: Option<hir::Name>,
+    ) {
+        if let Some(item) = render_variant_pat(RenderContext::new(ctx), variant, local_name) {
+            self.add(item);
+        }
+    }
+
+    pub(crate) fn add_struct_pat(
+        &mut self,
+        ctx: &CompletionContext,
+        strukt: hir::Struct,
+        local_name: Option<hir::Name>,
+    ) {
+        if let Some(item) = render_struct_pat(RenderContext::new(ctx), strukt, local_name) {
+            self.add(item);
+        }
+    }
+
     pub(crate) fn add_const(&mut self, ctx: &CompletionContext, constant: hir::Const) {
         if let Some(item) = render_const(RenderContext::new(ctx), constant) {
             self.add(item);
diff --git a/crates/completion/src/completions/pattern.rs b/crates/completion/src/completions/pattern.rs
index 4d56731ec..eee31098d 100644
--- a/crates/completion/src/completions/pattern.rs
+++ b/crates/completion/src/completions/pattern.rs
@@ -2,9 +2,9 @@
 
 use crate::{CompletionContext, Completions};
 
-/// Completes constats and paths in patterns.
+/// Completes constants and paths in patterns.
 pub(crate) fn complete_pattern(acc: &mut Completions, ctx: &CompletionContext) {
-    if !(ctx.is_pat_binding_or_const || ctx.is_irrefutable_let_pat_binding) {
+    if !(ctx.is_pat_binding_or_const || ctx.is_irrefutable_pat_binding) {
         return;
     }
     if ctx.record_pat_syntax.is_some() {
@@ -15,20 +15,21 @@ pub(crate) fn complete_pattern(acc: &mut Completions, ctx: &CompletionContext) {
     // suggest variants + auto-imports
     ctx.scope.process_all_names(&mut |name, res| {
         let add_resolution = match &res {
-            hir::ScopeDef::ModuleDef(def) => {
-                if ctx.is_irrefutable_let_pat_binding {
-                    matches!(def, hir::ModuleDef::Adt(hir::Adt::Struct(_)))
-                } else {
-                    matches!(
-                        def,
-                        hir::ModuleDef::Adt(hir::Adt::Enum(..))
-                            | hir::ModuleDef::Adt(hir::Adt::Struct(..))
-                            | hir::ModuleDef::Variant(..)
-                            | hir::ModuleDef::Const(..)
-                            | hir::ModuleDef::Module(..)
-                    )
+            hir::ScopeDef::ModuleDef(def) => match def {
+                hir::ModuleDef::Adt(hir::Adt::Struct(strukt)) => {
+                    acc.add_struct_pat(ctx, strukt.clone(), Some(name.clone()));
+                    true
                 }
-            }
+                hir::ModuleDef::Variant(variant) if !ctx.is_irrefutable_pat_binding => {
+                    acc.add_variant_pat(ctx, variant.clone(), Some(name.clone()));
+                    true
+                }
+                hir::ModuleDef::Adt(hir::Adt::Enum(..))
+                | hir::ModuleDef::Variant(..)
+                | hir::ModuleDef::Const(..)
+                | hir::ModuleDef::Module(..) => !ctx.is_irrefutable_pat_binding,
+                _ => false,
+            },
             hir::ScopeDef::MacroDef(_) => true,
             _ => false,
         };
@@ -42,13 +43,21 @@ pub(crate) fn complete_pattern(acc: &mut Completions, ctx: &CompletionContext) {
 mod tests {
     use expect_test::{expect, Expect};
 
-    use crate::{test_utils::completion_list, CompletionKind};
+    use crate::{
+        test_utils::{check_edit, completion_list},
+        CompletionKind,
+    };
 
     fn check(ra_fixture: &str, expect: Expect) {
         let actual = completion_list(ra_fixture, CompletionKind::Reference);
         expect.assert_eq(&actual)
     }
 
+    fn check_snippet(ra_fixture: &str, expect: Expect) {
+        let actual = completion_list(ra_fixture, CompletionKind::Snippet);
+        expect.assert_eq(&actual)
+    }
+
     #[test]
     fn completes_enum_variants_and_modules() {
         check(
@@ -69,7 +78,7 @@ fn foo() {
                 en E
                 ct Z
                 st Bar
-                ev X   ()
+                ev X
                 md m
             "#]],
         );
@@ -114,4 +123,139 @@ fn foo() {
             "#]],
         );
     }
+
+    #[test]
+    fn completes_in_param() {
+        check(
+            r#"
+enum E { X }
+
+static FOO: E = E::X;
+struct Bar { f: u32 }
+
+fn foo(<|>) {
+}
+"#,
+            expect![[r#"
+                st Bar
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_pat_in_let() {
+        check_snippet(
+            r#"
+struct Bar { f: u32 }
+
+fn foo() {
+   let <|>
+}
+"#,
+            expect![[r#"
+                bn Bar Bar { f$1 }$0
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_param_pattern() {
+        check_snippet(
+            r#"
+struct Foo { bar: String, baz: String }
+struct Bar(String, String);
+struct Baz;
+fn outer(<|>) {}
+"#,
+            expect![[r#"
+                bn Foo Foo { bar$1, baz$2 }: Foo$0
+                bn Bar Bar($1, $2): Bar$0
+            "#]],
+        )
+    }
+
+    #[test]
+    fn completes_let_pattern() {
+        check_snippet(
+            r#"
+struct Foo { bar: String, baz: String }
+struct Bar(String, String);
+struct Baz;
+fn outer() {
+    let <|>
+}
+"#,
+            expect![[r#"
+                bn Foo Foo { bar$1, baz$2 }$0
+                bn Bar Bar($1, $2)$0
+            "#]],
+        )
+    }
+
+    #[test]
+    fn completes_refutable_pattern() {
+        check_snippet(
+            r#"
+struct Foo { bar: i32, baz: i32 }
+struct Bar(String, String);
+struct Baz;
+fn outer() {
+    match () {
+        <|>
+    }
+}
+"#,
+            expect![[r#"
+                bn Foo Foo { bar$1, baz$2 }$0
+                bn Bar Bar($1, $2)$0
+            "#]],
+        )
+    }
+
+    #[test]
+    fn omits_private_fields_pat() {
+        check_snippet(
+            r#"
+mod foo {
+    pub struct Foo { pub bar: i32, baz: i32 }
+    pub struct Bar(pub String, String);
+    pub struct Invisible(String, String);
+}
+use foo::*;
+
+fn outer() {
+    match () {
+        <|>
+    }
+}
+"#,
+            expect![[r#"
+                bn Foo Foo { bar$1, .. }$0
+                bn Bar Bar($1, ..)$0
+            "#]],
+        )
+    }
+
+    #[test]
+    fn only_shows_ident_completion() {
+        check_edit(
+            "Foo",
+            r#"
+struct Foo(i32);
+fn main() {
+    match Foo(92) {
+        <|>(92) => (),
+    }
+}
+"#,
+            r#"
+struct Foo(i32);
+fn main() {
+    match Foo(92) {
+        Foo(92) => (),
+    }
+}
+"#,
+        );
+    }
 }
diff --git a/crates/completion/src/context.rs b/crates/completion/src/context.rs
index 5cd11cf77..41de324d8 100644
--- a/crates/completion/src/context.rs
+++ b/crates/completion/src/context.rs
@@ -51,7 +51,7 @@ pub(crate) struct CompletionContext<'a> {
     /// If a name-binding or reference to a const in a pattern.
     /// Irrefutable patterns (like let) are excluded.
     pub(super) is_pat_binding_or_const: bool,
-    pub(super) is_irrefutable_let_pat_binding: bool,
+    pub(super) is_irrefutable_pat_binding: bool,
     /// A single-indent path, like `foo`. `::foo` should not be considered a trivial path.
     pub(super) is_trivial_path: bool,
     /// If not a trivial path, the prefix (qualifier).
@@ -147,7 +147,7 @@ impl<'a> CompletionContext<'a> {
             active_parameter: ActiveParameter::at(db, position),
             is_param: false,
             is_pat_binding_or_const: false,
-            is_irrefutable_let_pat_binding: false,
+            is_irrefutable_pat_binding: false,
             is_trivial_path: false,
             path_qual: None,
             after_if: false,
@@ -327,14 +327,19 @@ impl<'a> CompletionContext<'a> {
                 if bind_pat.syntax().parent().and_then(ast::RecordPatFieldList::cast).is_some() {
                     self.is_pat_binding_or_const = false;
                 }
-                if let Some(let_stmt) = bind_pat.syntax().ancestors().find_map(ast::LetStmt::cast) {
-                    if let Some(pat) = let_stmt.pat() {
-                        if pat.syntax().text_range().contains_range(bind_pat.syntax().text_range())
-                        {
-                            self.is_pat_binding_or_const = false;
-                            self.is_irrefutable_let_pat_binding = true;
+                if let Some(Some(pat)) = bind_pat.syntax().ancestors().find_map(|node| {
+                    match_ast! {
+                        match node {
+                            ast::LetStmt(it) => Some(it.pat()),
+                            ast::Param(it) => Some(it.pat()),
+                            _ => None,
                         }
                     }
+                }) {
+                    if pat.syntax().text_range().contains_range(bind_pat.syntax().text_range()) {
+                        self.is_pat_binding_or_const = false;
+                        self.is_irrefutable_pat_binding = true;
+                    }
                 }
             }
             if is_node::<ast::Param>(name.syntax()) {
diff --git a/crates/completion/src/render.rs b/crates/completion/src/render.rs
index 1092a4825..1ba7201a1 100644
--- a/crates/completion/src/render.rs
+++ b/crates/completion/src/render.rs
@@ -5,6 +5,7 @@ pub(crate) mod macro_;
 pub(crate) mod function;
 pub(crate) mod enum_variant;
 pub(crate) mod const_;
+pub(crate) mod pattern;
 pub(crate) mod type_alias;
 
 mod builder_ext;
@@ -159,6 +160,12 @@ impl<'a> Render<'a> {
                 let item = render_fn(self.ctx, import_to_add, Some(local_name), *func);
                 return Some(item);
             }
+            ScopeDef::ModuleDef(Variant(_))
+                if self.ctx.completion.is_pat_binding_or_const
+                    | self.ctx.completion.is_irrefutable_pat_binding =>
+            {
+                CompletionItemKind::EnumVariant
+            }
             ScopeDef::ModuleDef(Variant(var)) => {
                 let item = render_variant(self.ctx, import_to_add, Some(local_name), *var, None);
                 return Some(item);
diff --git a/crates/completion/src/render/builder_ext.rs b/crates/completion/src/render/builder_ext.rs
index ce8718bd5..d053a988b 100644
--- a/crates/completion/src/render/builder_ext.rs
+++ b/crates/completion/src/render/builder_ext.rs
@@ -34,7 +34,6 @@ impl Builder {
             return false;
         }
         if ctx.is_pattern_call {
-            mark::hit!(dont_duplicate_pattern_parens);
             return false;
         }
         if ctx.is_call {
diff --git a/crates/completion/src/render/enum_variant.rs b/crates/completion/src/render/enum_variant.rs
index 7176fd9b3..732e139ec 100644
--- a/crates/completion/src/render/enum_variant.rs
+++ b/crates/completion/src/render/enum_variant.rs
@@ -126,50 +126,5 @@ fn main() -> Option<i32> {
 }
 "#,
         );
-        check_edit(
-            "Some",
-            r#"
-enum Option<T> { Some(T), None }
-use Option::*;
-fn main(value: Option<i32>) {
-    match value {
-        Som<|>
-    }
-}
-"#,
-            r#"
-enum Option<T> { Some(T), None }
-use Option::*;
-fn main(value: Option<i32>) {
-    match value {
-        Some($0)
-    }
-}
-"#,
-        );
-    }
-
-    #[test]
-    fn dont_duplicate_pattern_parens() {
-        mark::check!(dont_duplicate_pattern_parens);
-        check_edit(
-            "Var",
-            r#"
-enum E { Var(i32) }
-fn main() {
-    match E::Var(92) {
-        E::<|>(92) => (),
-    }
-}
-"#,
-            r#"
-enum E { Var(i32) }
-fn main() {
-    match E::Var(92) {
-        E::Var(92) => (),
-    }
-}
-"#,
-        );
     }
 }
diff --git a/crates/completion/src/render/pattern.rs b/crates/completion/src/render/pattern.rs
new file mode 100644
index 000000000..a3b6a3cac
--- /dev/null
+++ b/crates/completion/src/render/pattern.rs
@@ -0,0 +1,148 @@
+//! Renderer for patterns.
+
+use hir::{db::HirDatabase, HasAttrs, HasVisibility, Name, StructKind};
+use itertools::Itertools;
+
+use crate::{
+    config::SnippetCap, item::CompletionKind, render::RenderContext, CompletionItem,
+    CompletionItemKind,
+};
+
+fn visible_fields(
+    ctx: &RenderContext<'_>,
+    fields: &[hir::Field],
+    item: impl HasAttrs,
+) -> Option<(Vec<hir::Field>, bool)> {
+    let module = ctx.completion.scope.module()?;
+    let n_fields = fields.len();
+    let fields = fields
+        .into_iter()
+        .filter(|field| field.is_visible_from(ctx.db(), module))
+        .copied()
+        .collect::<Vec<_>>();
+
+    let fields_omitted =
+        n_fields - fields.len() > 0 || item.attrs(ctx.db()).by_key("non_exhaustive").exists();
+    Some((fields, fields_omitted))
+}
+
+pub(crate) fn render_struct_pat(
+    ctx: RenderContext<'_>,
+    strukt: hir::Struct,
+    local_name: Option<Name>,
+) -> Option<CompletionItem> {
+    let _p = profile::span("render_struct_pat");
+
+    let fields = strukt.fields(ctx.db());
+    let (visible_fields, fields_omitted) = visible_fields(&ctx, &fields, strukt)?;
+
+    if visible_fields.is_empty() {
+        // Matching a struct without matching its fields is pointless, unlike matching a Variant without its fields
+        return None;
+    }
+
+    let name = local_name.unwrap_or_else(|| strukt.name(ctx.db())).to_string();
+    let pat = render_pat(&ctx, &name, strukt.kind(ctx.db()), &visible_fields, fields_omitted)?;
+
+    Some(build_completion(ctx, name, pat, strukt))
+}
+
+pub(crate) fn render_variant_pat(
+    ctx: RenderContext<'_>,
+    variant: hir::Variant,
+    local_name: Option<Name>,
+) -> Option<CompletionItem> {
+    let _p = profile::span("render_variant_pat");
+
+    let fields = variant.fields(ctx.db());
+    let (visible_fields, fields_omitted) = visible_fields(&ctx, &fields, variant)?;
+
+    let name = local_name.unwrap_or_else(|| variant.name(ctx.db())).to_string();
+    let pat = render_pat(&ctx, &name, variant.kind(ctx.db()), &visible_fields, fields_omitted)?;
+
+    Some(build_completion(ctx, name, pat, variant))
+}
+
+fn build_completion(
+    ctx: RenderContext<'_>,
+    name: String,
+    pat: String,
+    item: impl HasAttrs + Copy,
+) -> CompletionItem {
+    let completion = CompletionItem::new(CompletionKind::Snippet, ctx.source_range(), name)
+        .kind(CompletionItemKind::Binding)
+        .set_documentation(ctx.docs(item))
+        .set_deprecated(ctx.is_deprecated(item))
+        .detail(&pat);
+    let completion = if let Some(snippet_cap) = ctx.snippet_cap() {
+        completion.insert_snippet(snippet_cap, pat)
+    } else {
+        completion.insert_text(pat)
+    };
+    completion.build()
+}
+
+fn render_pat(
+    ctx: &RenderContext<'_>,
+    name: &str,
+    kind: StructKind,
+    fields: &[hir::Field],
+    fields_omitted: bool,
+) -> Option<String> {
+    let mut pat = match kind {
+        StructKind::Tuple if ctx.snippet_cap().is_some() => {
+            render_tuple_as_pat(&fields, &name, fields_omitted)
+        }
+        StructKind::Record => {
+            render_record_as_pat(ctx.db(), ctx.snippet_cap(), &fields, &name, fields_omitted)
+        }
+        _ => return None,
+    };
+
+    if ctx.completion.is_param {
+        pat.push(':');
+        pat.push(' ');
+        pat.push_str(&name);
+    }
+    if ctx.snippet_cap().is_some() {
+        pat.push_str("$0");
+    }
+    Some(pat)
+}
+
+fn render_record_as_pat(
+    db: &dyn HirDatabase,
+    snippet_cap: Option<SnippetCap>,
+    fields: &[hir::Field],
+    name: &str,
+    fields_omitted: bool,
+) -> String {
+    let fields = fields.iter();
+    if snippet_cap.is_some() {
+        format!(
+            "{name} {{ {}{} }}",
+            fields
+                .enumerate()
+                .map(|(idx, field)| format!("{}${}", field.name(db), idx + 1))
+                .format(", "),
+            if fields_omitted { ", .." } else { "" },
+            name = name
+        )
+    } else {
+        format!(
+            "{name} {{ {}{} }}",
+            fields.map(|field| field.name(db)).format(", "),
+            if fields_omitted { ", .." } else { "" },
+            name = name
+        )
+    }
+}
+
+fn render_tuple_as_pat(fields: &[hir::Field], name: &str, fields_omitted: bool) -> String {
+    format!(
+        "{name}({}{})",
+        fields.iter().enumerate().map(|(idx, _)| format!("${}", idx + 1)).format(", "),
+        if fields_omitted { ", .." } else { "" },
+        name = name
+    )
+}
diff --git a/crates/hir/src/code_model.rs b/crates/hir/src/code_model.rs
index 73ca6ba9f..1d7e5ddd7 100644
--- a/crates/hir/src/code_model.rs
+++ b/crates/hir/src/code_model.rs
@@ -511,6 +511,10 @@ impl Struct {
         db.struct_data(self.id).repr.clone()
     }
 
+    pub fn kind(self, db: &dyn HirDatabase) -> StructKind {
+        self.variant_data(db).kind()
+    }
+
     fn variant_data(self, db: &dyn HirDatabase) -> Arc<VariantData> {
         db.struct_data(self.id).variant_data.clone()
     }
diff --git a/crates/rust-analyzer/src/config.rs b/crates/rust-analyzer/src/config.rs
index 1f4b5c24c..11cdae57f 100644
--- a/crates/rust-analyzer/src/config.rs
+++ b/crates/rust-analyzer/src/config.rs
@@ -33,7 +33,7 @@ config_data! {
         callInfo_full: bool = "true",
 
         /// Automatically refresh project info via `cargo metadata` on
-        /// Cargo.toml changes.
+        /// `Cargo.toml` changes.
         cargo_autoreload: bool           = "true",
         /// Activate all available features.
         cargo_allFeatures: bool          = "false",
@@ -52,7 +52,7 @@ config_data! {
         /// Run specified `cargo check` command for diagnostics on save.
         checkOnSave_enable: bool                         = "true",
         /// Check with all features (will be passed as `--all-features`).
-        /// Defaults to `rust-analyzer.cargo.allFeatures`.
+        /// Defaults to `#rust-analyzer.cargo.allFeatures#`.
         checkOnSave_allFeatures: Option<bool>            = "null",
         /// Check all targets and tests (will be passed as `--all-targets`).
         checkOnSave_allTargets: bool                     = "true",
@@ -61,12 +61,12 @@ config_data! {
         /// Do not activate the `default` feature.
         checkOnSave_noDefaultFeatures: Option<bool>      = "null",
         /// Check for a specific target. Defaults to
-        /// `rust-analyzer.cargo.target`.
+        /// `#rust-analyzer.cargo.target#`.
         checkOnSave_target: Option<String>               = "null",
         /// Extra arguments for `cargo check`.
         checkOnSave_extraArgs: Vec<String>               = "[]",
         /// List of features to activate. Defaults to
-        /// `rust-analyzer.cargo.features`.
+        /// `#rust-analyzer.cargo.features#`.
         checkOnSave_features: Option<Vec<String>>        = "null",
         /// Advanced option, fully override the command rust-analyzer uses for
         /// checking. The command should include `--message-format=json` or
@@ -80,7 +80,7 @@ config_data! {
         /// Whether to show postfix snippets like `dbg`, `if`, `not`, etc.
         completion_postfix_enable: bool          = "true",
         /// Toggles the additional completions that automatically add imports when completed.
-        /// Note that your client have to specify the `additionalTextEdits` LSP client capability to truly have this feature enabled.
+        /// Note that your client must specify the `additionalTextEdits` LSP client capability to truly have this feature enabled.
         completion_autoimport_enable: bool       = "true",
 
         /// Whether to show native rust-analyzer diagnostics.
@@ -90,13 +90,13 @@ config_data! {
         diagnostics_enableExperimental: bool    = "true",
         /// List of rust-analyzer diagnostics to disable.
         diagnostics_disabled: FxHashSet<String> = "[]",
-        /// List of warnings that should be displayed with info severity.\nThe
+        /// List of warnings that should be displayed with info severity.\n\nThe
         /// warnings will be indicated by a blue squiggly underline in code and
-        /// a blue icon in the problems panel.
+        /// a blue icon in the `Problems Panel`.
         diagnostics_warningsAsHint: Vec<String> = "[]",
-        /// List of warnings that should be displayed with hint severity.\nThe
+        /// List of warnings that should be displayed with hint severity.\n\nThe
         /// warnings will be indicated by faded text or three dots in code and
-        /// will not show up in the problems panel.
+        /// will not show up in the `Problems Panel`.
         diagnostics_warningsAsInfo: Vec<String> = "[]",
 
         /// Controls file watching implementation.
@@ -121,7 +121,7 @@ config_data! {
 
         /// Whether to show inlay type hints for method chains.
         inlayHints_chainingHints: bool      = "true",
-        /// Maximum length for inlay hints.
+        /// Maximum length for inlay hints. Default is unlimited.
         inlayHints_maxLength: Option<usize> = "null",
         /// Whether to show function parameter name inlay hints at the call
         /// site.
@@ -145,27 +145,27 @@ config_data! {
         lens_methodReferences: bool = "false",
 
         /// Disable project auto-discovery in favor of explicitly specified set
-        /// of projects.  \nElements must be paths pointing to Cargo.toml,
-        /// rust-project.json, or JSON objects in rust-project.json format.
+        /// of projects.\n\nElements must be paths pointing to `Cargo.toml`,
+        /// `rust-project.json`, or JSON objects in `rust-project.json` format.
         linkedProjects: Vec<ManifestOrProjectJson> = "[]",
-        /// Number of syntax trees rust-analyzer keeps in memory.
+        /// Number of syntax trees rust-analyzer keeps in memory.  Defaults to 128.
         lruCapacity: Option<usize>                 = "null",
         /// Whether to show `can't find Cargo.toml` error message.
         notifications_cargoTomlNotFound: bool      = "true",
-        /// Enable Proc macro support, cargo.loadOutDirsFromCheck must be
+        /// Enable Proc macro support, `#rust-analyzer.cargo.loadOutDirsFromCheck#` must be
         /// enabled.
         procMacro_enable: bool                     = "false",
 
         /// Command to be executed instead of 'cargo' for runnables.
         runnables_overrideCargo: Option<String> = "null",
         /// Additional arguments to be passed to cargo for runnables such as
-        /// tests or binaries.\nFor example, it may be '--release'.
+        /// tests or binaries.\nFor example, it may be `--release`.
         runnables_cargoExtraArgs: Vec<String>   = "[]",
 
         /// Path to the rust compiler sources, for usage in rustc_private projects.
         rustcSource : Option<String> = "null",
 
-        /// Additional arguments to rustfmt.
+        /// Additional arguments to `rustfmt`.
         rustfmt_extraArgs: Vec<String>               = "[]",
         /// Advanced option, fully override the command rust-analyzer uses for
         /// formatting.
@@ -758,7 +758,7 @@ fn field_props(field: &str, ty: &str, doc: &[&str], default: &str) -> serde_json
             ],
             "enumDescriptions": [
                 "Insert import paths relative to the current module, using up to one `super` prefix if the parent module contains the requested item.",
-                "Prefix all import paths with `self` if they don't begin with `self`, `super`, `crate` or a crate name",
+                "Prefix all import paths with `self` if they don't begin with `self`, `super`, `crate` or a crate name.",
                 "Force import paths to be absolute by always starting them with `crate` or the crate name they refer to."
             ],
         },