1 use ide_db::defs::{Definition, NameRefClass};
2 use syntax::{ast, AstNode, SyntaxKind, T};
6 assist_context::{AssistContext, Assists},
10 // Assist: add_turbo_fish
12 // Adds `::<_>` to a call of a generic method or function.
15 // fn make<T>() -> T { todo!() }
22 // fn make<T>() -> T { todo!() }
24 // let x = make::<${0:_}>();
27 pub(crate) fn add_turbo_fish(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
28 let ident = ctx.find_token_syntax_at_offset(SyntaxKind::IDENT).or_else(|| {
29 let arg_list = ctx.find_node_at_offset::<ast::ArgList>()?;
30 if arg_list.args().count() > 0 {
33 mark::hit!(add_turbo_fish_after_call);
34 mark::hit!(add_type_ascription_after_call);
35 arg_list.l_paren_token()?.prev_token().filter(|it| it.kind() == SyntaxKind::IDENT)
37 let next_token = ident.next_token()?;
38 if next_token.kind() == T![::] {
39 mark::hit!(add_turbo_fish_one_fish_is_enough);
42 let name_ref = ast::NameRef::cast(ident.parent())?;
43 let def = match NameRefClass::classify(&ctx.sema, &name_ref)? {
44 NameRefClass::Definition(def) => def,
45 NameRefClass::ExternCrate(_) | NameRefClass::FieldShorthand { .. } => return None,
48 Definition::ModuleDef(hir::ModuleDef::Function(it)) => it,
51 let generics = hir::GenericDef::Function(fun).params(ctx.sema.db);
52 if generics.is_empty() {
53 mark::hit!(add_turbo_fish_non_generic);
57 if let Some(let_stmt) = ctx.find_node_at_offset::<ast::LetStmt>() {
58 if let_stmt.colon_token().is_none() {
59 let type_pos = let_stmt.pat()?.syntax().last_token()?.text_range().end();
61 AssistId("add_type_ascription", AssistKind::RefactorRewrite),
62 "Add `: _` before assignment operator",
64 |builder| match ctx.config.snippet_cap {
65 Some(cap) => builder.insert_snippet(cap, type_pos, ": ${0:_}"),
66 None => builder.insert(type_pos, ": _"),
70 mark::hit!(add_type_ascription_already_typed);
75 AssistId("add_turbo_fish", AssistKind::RefactorRewrite),
78 |builder| match ctx.config.snippet_cap {
79 Some(cap) => builder.insert_snippet(cap, ident.text_range().end(), "::<${0:_}>"),
80 None => builder.insert(ident.text_range().end(), "::<_>"),
87 use crate::tests::{check_assist, check_assist_by_label, check_assist_not_applicable};
93 fn add_turbo_fish_function() {
112 fn add_turbo_fish_after_call() {
113 mark::check!(add_turbo_fish_after_call);
132 fn add_turbo_fish_method() {
138 fn make<T>(&self) -> T {}
147 fn make<T>(&self) -> T {}
157 fn add_turbo_fish_one_fish_is_enough() {
158 mark::check!(add_turbo_fish_one_fish_is_enough);
159 check_assist_not_applicable(
171 fn add_turbo_fish_non_generic() {
172 mark::check!(add_turbo_fish_non_generic);
173 check_assist_not_applicable(
185 fn add_type_ascription_function() {
186 check_assist_by_label(
197 let x: ${0:_} = make();
200 "Add `: _` before assignment operator",
205 fn add_type_ascription_after_call() {
206 mark::check!(add_type_ascription_after_call);
207 check_assist_by_label(
218 let x: ${0:_} = make();
221 "Add `: _` before assignment operator",
226 fn add_type_ascription_method() {
227 check_assist_by_label(
232 fn make<T>(&self) -> T {}
241 fn make<T>(&self) -> T {}
244 let x: ${0:_} = S.make();
247 "Add `: _` before assignment operator",
252 fn add_type_ascription_already_typed() {
253 mark::check!(add_type_ascription_already_typed);
259 let x: () = make$0();
265 let x: () = make::<${0:_}>();