6 files changed, 317 insertions, 49 deletions

diff --git a/crates/ra_assists/src/doc_tests/generated.rs b/crates/ra_assists/src/doc_tests/generated.rs
index 64444ee3a..b39e60870 100644
--- a/crates/ra_assists/src/doc_tests/generated.rs
+++ b/crates/ra_assists/src/doc_tests/generated.rs
@@ -78,7 +78,7 @@ fn foo() {
 }
 
 fn bar(arg: &str, baz: Baz) {
-    unimplemented!()
+    todo!()
 }
 
 "#####,
@@ -180,7 +180,7 @@ trait Trait<T> {
 }
 
 impl Trait<u32> for () {
-    fn foo(&self) -> u32 { unimplemented!() }
+    fn foo(&self) -> u32 { todo!() }
 
 }
 "#####,
@@ -607,6 +607,21 @@ impl Walrus {
 }
 
 #[test]
+fn doctest_reorder_fields() {
+    check(
+        "reorder_fields",
+        r#####"
+struct Foo {foo: i32, bar: i32};
+const test: Foo = <|>Foo {bar: 0, foo: 1}
+"#####,
+        r#####"
+struct Foo {foo: i32, bar: i32};
+const test: Foo = Foo {foo: 1, bar: 0}
+"#####,
+    )
+}
+
+#[test]
 fn doctest_replace_if_let_with_match() {
     check(
         "replace_if_let_with_match",
diff --git a/crates/ra_assists/src/handlers/add_function.rs b/crates/ra_assists/src/handlers/add_function.rs
index 488bae08f..ad4ab66ed 100644
--- a/crates/ra_assists/src/handlers/add_function.rs
+++ b/crates/ra_assists/src/handlers/add_function.rs
@@ -29,7 +29,7 @@ use rustc_hash::{FxHashMap, FxHashSet};
 // }
 //
 // fn bar(arg: &str, baz: Baz) {
-//     unimplemented!()
+//     todo!()
 // }
 //
 // ```
@@ -80,7 +80,7 @@ impl FunctionBuilder {
         Some(Self { append_fn_at, fn_name, type_params, params })
     }
     fn render(self) -> Option<FunctionTemplate> {
-        let placeholder_expr = ast::make::expr_unimplemented();
+        let placeholder_expr = ast::make::expr_todo();
         let fn_body = ast::make::block_expr(vec![], Some(placeholder_expr));
         let fn_def = ast::make::fn_def(self.fn_name, self.type_params, self.params, fn_body);
         let fn_def = ast::make::add_newlines(2, fn_def);
@@ -225,7 +225,7 @@ fn foo() {
 }
 
 fn bar() {
-    <|>unimplemented!()
+    <|>todo!()
 }
 ",
         )
@@ -252,7 +252,7 @@ impl Foo {
 }
 
 fn bar() {
-    <|>unimplemented!()
+    <|>todo!()
 }
 ",
         )
@@ -276,7 +276,7 @@ fn foo1() {
 }
 
 fn bar() {
-    <|>unimplemented!()
+    <|>todo!()
 }
 
 fn foo2() {}
@@ -302,7 +302,7 @@ mod baz {
     }
 
     fn bar() {
-        <|>unimplemented!()
+        <|>todo!()
     }
 }
 ",
@@ -315,20 +315,20 @@ mod baz {
             add_function,
             r"
 struct Baz;
-fn baz() -> Baz { unimplemented!() }
+fn baz() -> Baz { todo!() }
 fn foo() {
     bar<|>(baz());
 }
 ",
             r"
 struct Baz;
-fn baz() -> Baz { unimplemented!() }
+fn baz() -> Baz { todo!() }
 fn foo() {
     bar(baz());
 }
 
 fn bar(baz: Baz) {
-    <|>unimplemented!()
+    <|>todo!()
 }
 ",
         );
@@ -361,7 +361,7 @@ impl Baz {
 }
 
 fn bar(baz: Baz) {
-    <|>unimplemented!()
+    <|>todo!()
 }
 ",
         )
@@ -382,7 +382,7 @@ fn foo() {
 }
 
 fn bar(arg: &str) {
-    <|>unimplemented!()
+    <|>todo!()
 }
 "#,
         )
@@ -403,7 +403,7 @@ fn foo() {
 }
 
 fn bar(arg: char) {
-    <|>unimplemented!()
+    <|>todo!()
 }
 "#,
         )
@@ -424,7 +424,7 @@ fn foo() {
 }
 
 fn bar(arg: i32) {
-    <|>unimplemented!()
+    <|>todo!()
 }
 ",
         )
@@ -445,7 +445,7 @@ fn foo() {
 }
 
 fn bar(arg: u8) {
-    <|>unimplemented!()
+    <|>todo!()
 }
 ",
         )
@@ -470,7 +470,7 @@ fn foo() {
 }
 
 fn bar(x: u8) {
-    <|>unimplemented!()
+    <|>todo!()
 }
 ",
         )
@@ -493,7 +493,7 @@ fn foo() {
 }
 
 fn bar(worble: ()) {
-    <|>unimplemented!()
+    <|>todo!()
 }
 ",
         )
@@ -506,7 +506,7 @@ fn bar(worble: ()) {
             r"
 trait Foo {}
 fn foo() -> impl Foo {
-    unimplemented!()
+    todo!()
 }
 fn baz() {
     <|>bar(foo())
@@ -515,14 +515,14 @@ fn baz() {
             r"
 trait Foo {}
 fn foo() -> impl Foo {
-    unimplemented!()
+    todo!()
 }
 fn baz() {
     bar(foo())
 }
 
 fn bar(foo: impl Foo) {
-    <|>unimplemented!()
+    <|>todo!()
 }
 ",
         )
@@ -556,7 +556,7 @@ mod Foo {
     }
 
     fn bar(baz: super::Baz::Bof) {
-        <|>unimplemented!()
+        <|>todo!()
     }
 }
 ",
@@ -580,7 +580,7 @@ fn foo<T>(t: T) {
 }
 
 fn bar<T>(t: T) {
-    <|>unimplemented!()
+    <|>todo!()
 }
 ",
         )
@@ -611,7 +611,7 @@ fn foo() {
 }
 
 fn bar(arg: fn() -> Baz) {
-    <|>unimplemented!()
+    <|>todo!()
 }
 ",
         )
@@ -636,7 +636,7 @@ fn foo() {
 }
 
 fn bar(closure: impl Fn(i64) -> i64) {
-    <|>unimplemented!()
+    <|>todo!()
 }
 ",
         )
@@ -657,7 +657,7 @@ fn foo() {
 }
 
 fn bar(baz: ()) {
-    <|>unimplemented!()
+    <|>todo!()
 }
 ",
         )
@@ -682,7 +682,7 @@ fn foo() {
 }
 
 fn bar(baz_1: Baz, baz_2: Baz) {
-    <|>unimplemented!()
+    <|>todo!()
 }
 ",
         )
@@ -707,7 +707,7 @@ fn foo() {
 }
 
 fn bar(baz_1: Baz, baz_2: Baz, arg_1: &str, arg_2: &str) {
-    <|>unimplemented!()
+    <|>todo!()
 }
 "#,
         )
@@ -779,7 +779,7 @@ impl Foo {
         self.bar();
     }
     fn bar(&self) {
-        unimplemented!();
+        todo!();
     }
 }
         ",
diff --git a/crates/ra_assists/src/handlers/add_missing_impl_members.rs b/crates/ra_assists/src/handlers/add_missing_impl_members.rs
index 722f207e2..2d6d44980 100644
--- a/crates/ra_assists/src/handlers/add_missing_impl_members.rs
+++ b/crates/ra_assists/src/handlers/add_missing_impl_members.rs
@@ -40,7 +40,7 @@ enum AddMissingImplMembersMode {
 // }
 //
 // impl Trait<u32> for () {
-//     fn foo(&self) -> u32 { unimplemented!() }
+//     fn foo(&self) -> u32 { todo!() }
 //
 // }
 // ```
@@ -165,7 +165,7 @@ fn add_missing_impl_members_inner(
 
 fn add_body(fn_def: ast::FnDef) -> ast::FnDef {
     if fn_def.body().is_none() {
-        fn_def.with_body(make::block_from_expr(make::expr_unimplemented()))
+        fn_def.with_body(make::block_from_expr(make::expr_todo()))
     } else {
         fn_def
     }
@@ -215,8 +215,8 @@ impl Foo for S {
     fn bar(&self) {}
     <|>type Output;
     const CONST: usize = 42;
-    fn foo(&self) { unimplemented!() }
-    fn baz(&self) { unimplemented!() }
+    fn foo(&self) { todo!() }
+    fn baz(&self) { todo!() }
 
 }",
         );
@@ -250,7 +250,7 @@ struct S;
 
 impl Foo for S {
     fn bar(&self) {}
-    <|>fn foo(&self) { unimplemented!() }
+    <|>fn foo(&self) { todo!() }
 
 }",
         );
@@ -268,7 +268,7 @@ impl Foo for S { <|> }",
 trait Foo { fn foo(&self); }
 struct S;
 impl Foo for S {
-    <|>fn foo(&self) { unimplemented!() }
+    <|>fn foo(&self) { todo!() }
 }",
         );
     }
@@ -285,7 +285,7 @@ impl Foo<u32> for S { <|> }",
 trait Foo<T> { fn foo(&self, t: T) -> &T; }
 struct S;
 impl Foo<u32> for S {
-    <|>fn foo(&self, t: u32) -> &u32 { unimplemented!() }
+    <|>fn foo(&self, t: u32) -> &u32 { todo!() }
 }",
         );
     }
@@ -302,7 +302,7 @@ impl<U> Foo<U> for S { <|> }",
 trait Foo<T> { fn foo(&self, t: T) -> &T; }
 struct S;
 impl<U> Foo<U> for S {
-    <|>fn foo(&self, t: U) -> &U { unimplemented!() }
+    <|>fn foo(&self, t: U) -> &U { todo!() }
 }",
         );
     }
@@ -319,7 +319,7 @@ impl Foo for S {}<|>",
 trait Foo { fn foo(&self); }
 struct S;
 impl Foo for S {
-    <|>fn foo(&self) { unimplemented!() }
+    <|>fn foo(&self) { todo!() }
 }",
         )
     }
@@ -342,7 +342,7 @@ mod foo {
 }
 struct S;
 impl foo::Foo for S {
-    <|>fn foo(&self, bar: foo::Bar) { unimplemented!() }
+    <|>fn foo(&self, bar: foo::Bar) { todo!() }
 }",
         );
     }
@@ -365,7 +365,7 @@ mod foo {
 }
 struct S;
 impl foo::Foo for S {
-    <|>fn foo(&self, bar: foo::Bar<u32>) { unimplemented!() }
+    <|>fn foo(&self, bar: foo::Bar<u32>) { todo!() }
 }",
         );
     }
@@ -388,7 +388,7 @@ mod foo {
 }
 struct S;
 impl foo::Foo<u32> for S {
-    <|>fn foo(&self, bar: foo::Bar<u32>) { unimplemented!() }
+    <|>fn foo(&self, bar: foo::Bar<u32>) { todo!() }
 }",
         );
     }
@@ -414,7 +414,7 @@ mod foo {
 struct Param;
 struct S;
 impl foo::Foo<Param> for S {
-    <|>fn foo(&self, bar: Param) { unimplemented!() }
+    <|>fn foo(&self, bar: Param) { todo!() }
 }",
         );
     }
@@ -439,7 +439,7 @@ mod foo {
 }
 struct S;
 impl foo::Foo for S {
-    <|>fn foo(&self, bar: foo::Bar<u32>::Assoc) { unimplemented!() }
+    <|>fn foo(&self, bar: foo::Bar<u32>::Assoc) { todo!() }
 }",
         );
     }
@@ -464,7 +464,7 @@ mod foo {
 }
 struct S;
 impl foo::Foo for S {
-    <|>fn foo(&self, bar: foo::Bar<foo::Baz>) { unimplemented!() }
+    <|>fn foo(&self, bar: foo::Bar<foo::Baz>) { todo!() }
 }",
         );
     }
@@ -487,7 +487,7 @@ mod foo {
 }
 struct S;
 impl foo::Foo for S {
-    <|>fn foo(&self, bar: dyn Fn(u32) -> i32) { unimplemented!() }
+    <|>fn foo(&self, bar: dyn Fn(u32) -> i32) { todo!() }
 }",
         );
     }
@@ -544,7 +544,7 @@ trait Foo {
 struct S;
 impl Foo for S {
     <|>type Output;
-    fn foo(&self) { unimplemented!() }
+    fn foo(&self) { todo!() }
 }"#,
         )
     }
diff --git a/crates/ra_assists/src/handlers/merge_imports.rs b/crates/ra_assists/src/handlers/merge_imports.rs
index 0958f52f1..ef0ce0586 100644
--- a/crates/ra_assists/src/handlers/merge_imports.rs
+++ b/crates/ra_assists/src/handlers/merge_imports.rs
@@ -1,7 +1,7 @@
 use std::iter::successors;
 
 use ra_syntax::{
-    algo::{neighbor, SyntaxRewriter},
+    algo::{neighbor, skip_trivia_token, SyntaxRewriter},
     ast::{self, edit::AstNodeEdit, make},
     AstNode, Direction, InsertPosition, SyntaxElement, T,
 };
@@ -72,9 +72,18 @@ fn try_merge_trees(old: &ast::UseTree, new: &ast::UseTree) -> Option<ast::UseTre
     let lhs = old.split_prefix(&lhs_prefix);
     let rhs = new.split_prefix(&rhs_prefix);
 
+    let should_insert_comma = lhs
+        .use_tree_list()?
+        .r_curly_token()
+        .and_then(|it| skip_trivia_token(it.prev_token()?, Direction::Prev))
+        .map(|it| it.kind() != T![,])
+        .unwrap_or(true);
+
     let mut to_insert: Vec<SyntaxElement> = Vec::new();
-    to_insert.push(make::token(T![,]).into());
-    to_insert.push(make::tokens::single_space().into());
+    if should_insert_comma {
+        to_insert.push(make::token(T![,]).into());
+        to_insert.push(make::tokens::single_space().into());
+    }
     to_insert.extend(
         rhs.use_tree_list()?
             .syntax()
@@ -247,4 +256,22 @@ use {
 ",
         );
     }
+
+    #[test]
+    fn test_double_comma() {
+        check_assist(
+            merge_imports,
+            r"
+use foo::bar::baz;
+use foo::<|>{
+    FooBar,
+};
+",
+            r"
+use foo::{<|>
+    FooBar,
+bar::baz};
+",
+        )
+    }
 }
diff --git a/crates/ra_assists/src/handlers/reorder_fields.rs b/crates/ra_assists/src/handlers/reorder_fields.rs
new file mode 100644
index 000000000..5cbb98d73
--- /dev/null
+++ b/crates/ra_assists/src/handlers/reorder_fields.rs
@@ -0,0 +1,224 @@
+use std::collections::HashMap;
+
+use hir::{Adt, ModuleDef, PathResolution, Semantics, Struct};
+use itertools::Itertools;
+use ra_ide_db::RootDatabase;
+use ra_syntax::{
+    algo,
+    ast::{self, Path, RecordLit, RecordPat},
+    match_ast, AstNode, SyntaxKind,
+    SyntaxKind::*,
+    SyntaxNode,
+};
+
+use crate::{
+    assist_ctx::{Assist, AssistCtx},
+    AssistId,
+};
+
+// Assist: reorder_fields
+//
+// Reorder the fields of record literals and record patterns in the same order as in
+// the definition.
+//
+// ```
+// struct Foo {foo: i32, bar: i32};
+// const test: Foo = <|>Foo {bar: 0, foo: 1}
+// ```
+// ->
+// ```
+// struct Foo {foo: i32, bar: i32};
+// const test: Foo = Foo {foo: 1, bar: 0}
+// ```
+//
+pub(crate) fn reorder_fields(ctx: AssistCtx) -> Option<Assist> {
+    reorder::<RecordLit>(ctx.clone()).or_else(|| reorder::<RecordPat>(ctx))
+}
+
+fn reorder<R: AstNode>(ctx: AssistCtx) -> Option<Assist> {
+    let record = ctx.find_node_at_offset::<R>()?;
+    let path = record.syntax().children().find_map(Path::cast)?;
+
+    let ranks = compute_fields_ranks(&path, &ctx)?;
+
+    let fields = get_fields(&record.syntax());
+    let sorted_fields = sorted_by_rank(&fields, |node| {
+        *ranks.get(&get_field_name(node)).unwrap_or(&usize::max_value())
+    });
+
+    if sorted_fields == fields {
+        return None;
+    }
+
+    ctx.add_assist(AssistId("reorder_fields"), "Reorder record fields", |edit| {
+        for (old, new) in fields.iter().zip(&sorted_fields) {
+            algo::diff(old, new).into_text_edit(edit.text_edit_builder());
+        }
+        edit.target(record.syntax().text_range())
+    })
+}
+
+fn get_fields_kind(node: &SyntaxNode) -> Vec<SyntaxKind> {
+    match node.kind() {
+        RECORD_LIT => vec![RECORD_FIELD],
+        RECORD_PAT => vec![RECORD_FIELD_PAT, BIND_PAT],
+        _ => vec![],
+    }
+}
+
+fn get_field_name(node: &SyntaxNode) -> String {
+    let res = match_ast! {
+        match node {
+            ast::RecordField(field) => field.field_name().map(|it| it.to_string()),
+            ast::RecordFieldPat(field) => field.field_name().map(|it| it.to_string()),
+            _ => None,
+        }
+    };
+    res.unwrap_or_default()
+}
+
+fn get_fields(record: &SyntaxNode) -> Vec<SyntaxNode> {
+    let kinds = get_fields_kind(record);
+    record.children().flat_map(|n| n.children()).filter(|n| kinds.contains(&n.kind())).collect()
+}
+
+fn sorted_by_rank(
+    fields: &[SyntaxNode],
+    get_rank: impl Fn(&SyntaxNode) -> usize,
+) -> Vec<SyntaxNode> {
+    fields.iter().cloned().sorted_by_key(get_rank).collect()
+}
+
+fn struct_definition(path: &ast::Path, sema: &Semantics<RootDatabase>) -> Option<Struct> {
+    match sema.resolve_path(path) {
+        Some(PathResolution::Def(ModuleDef::Adt(Adt::Struct(s)))) => Some(s),
+        _ => None,
+    }
+}
+
+fn compute_fields_ranks(path: &Path, ctx: &AssistCtx) -> Option<HashMap<String, usize>> {
+    Some(
+        struct_definition(path, ctx.sema)?
+            .fields(ctx.db)
+            .iter()
+            .enumerate()
+            .map(|(idx, field)| (field.name(ctx.db).to_string(), idx))
+            .collect(),
+    )
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::helpers::{check_assist, check_assist_not_applicable};
+
+    use super::*;
+
+    #[test]
+    fn not_applicable_if_sorted() {
+        check_assist_not_applicable(
+            reorder_fields,
+            r#"
+        struct Foo {
+            foo: i32,
+            bar: i32,
+        }
+
+        const test: Foo = <|>Foo { foo: 0, bar: 0 };
+        "#,
+        )
+    }
+
+    #[test]
+    fn trivial_empty_fields() {
+        check_assist_not_applicable(
+            reorder_fields,
+            r#"
+        struct Foo {};
+        const test: Foo = <|>Foo {}
+        "#,
+        )
+    }
+
+    #[test]
+    fn reorder_struct_fields() {
+        check_assist(
+            reorder_fields,
+            r#"
+        struct Foo {foo: i32, bar: i32};
+        const test: Foo = <|>Foo {bar: 0, foo: 1}
+        "#,
+            r#"
+        struct Foo {foo: i32, bar: i32};
+        const test: Foo = <|>Foo {foo: 1, bar: 0}
+        "#,
+        )
+    }
+
+    #[test]
+    fn reorder_struct_pattern() {
+        check_assist(
+            reorder_fields,
+            r#"
+        struct Foo { foo: i64, bar: i64, baz: i64 }
+
+        fn f(f: Foo) -> {
+            match f {
+                <|>Foo { baz: 0, ref mut bar, .. } => (),
+                _ => ()
+            }
+        }
+        "#,
+            r#"
+        struct Foo { foo: i64, bar: i64, baz: i64 }
+
+        fn f(f: Foo) -> {
+            match f {
+                <|>Foo { ref mut bar, baz: 0, .. } => (),
+                _ => ()
+            }
+        }
+        "#,
+        )
+    }
+
+    #[test]
+    fn reorder_with_extra_field() {
+        check_assist(
+            reorder_fields,
+            r#"
+            struct Foo {
+                foo: String,
+                bar: String,
+            }
+
+            impl Foo {
+                fn new() -> Foo {
+                    let foo = String::new();
+                    <|>Foo {
+                        bar: foo.clone(),
+                        extra: "Extra field",
+                        foo,
+                    }
+                }
+            }
+            "#,
+            r#"
+            struct Foo {
+                foo: String,
+                bar: String,
+            }
+
+            impl Foo {
+                fn new() -> Foo {
+                    let foo = String::new();
+                    <|>Foo {
+                        foo,
+                        bar: foo.clone(),
+                        extra: "Extra field",
+                    }
+                }
+            }
+            "#,
+        )
+    }
+}
diff --git a/crates/ra_assists/src/lib.rs b/crates/ra_assists/src/lib.rs
index 5ba5254fd..a00136da1 100644
--- a/crates/ra_assists/src/lib.rs
+++ b/crates/ra_assists/src/lib.rs
@@ -129,6 +129,7 @@ mod handlers {
     mod replace_unwrap_with_match;
     mod split_import;
     mod add_from_impl_for_enum;
+    mod reorder_fields;
 
     pub(crate) fn all() -> &'static [AssistHandler] {
         &[
@@ -170,6 +171,7 @@ mod handlers {
             // These are manually sorted for better priorities
             add_missing_impl_members::add_missing_impl_members,
             add_missing_impl_members::add_missing_default_members,
+            reorder_fields::reorder_fields,
         ]
     }
 }