1 use ide_db::defs::{Definition, NameRefClass};
2 use syntax::{ast, AstNode, SyntaxKind, T};
5 assist_context::{AssistContext, Assists},
9 // Assist: add_turbo_fish
11 // Adds `::<_>` to a call of a generic method or function.
14 // fn make<T>() -> T { todo!() }
21 // fn make<T>() -> T { todo!() }
23 // let x = make::<${0:_}>();
26 pub(crate) fn add_turbo_fish(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
27 let ident = ctx.find_token_syntax_at_offset(SyntaxKind::IDENT).or_else(|| {
28 let arg_list = ctx.find_node_at_offset::<ast::ArgList>()?;
29 if arg_list.args().count() > 0 {
32 cov_mark::hit!(add_turbo_fish_after_call);
33 cov_mark::hit!(add_type_ascription_after_call);
34 arg_list.l_paren_token()?.prev_token().filter(|it| it.kind() == SyntaxKind::IDENT)
36 let next_token = ident.next_token()?;
37 if next_token.kind() == T![::] {
38 cov_mark::hit!(add_turbo_fish_one_fish_is_enough);
41 let name_ref = ast::NameRef::cast(ident.parent())?;
42 let def = match NameRefClass::classify(&ctx.sema, &name_ref)? {
43 NameRefClass::Definition(def) => def,
44 NameRefClass::ExternCrate(_) | NameRefClass::FieldShorthand { .. } => return None,
47 Definition::ModuleDef(hir::ModuleDef::Function(it)) => it,
50 let generics = hir::GenericDef::Function(fun).params(ctx.sema.db);
51 if generics.is_empty() {
52 cov_mark::hit!(add_turbo_fish_non_generic);
56 if let Some(let_stmt) = ctx.find_node_at_offset::<ast::LetStmt>() {
57 if let_stmt.colon_token().is_none() {
58 let type_pos = let_stmt.pat()?.syntax().last_token()?.text_range().end();
60 AssistId("add_type_ascription", AssistKind::RefactorRewrite),
61 "Add `: _` before assignment operator",
63 |builder| match ctx.config.snippet_cap {
64 Some(cap) => builder.insert_snippet(cap, type_pos, ": ${0:_}"),
65 None => builder.insert(type_pos, ": _"),
69 cov_mark::hit!(add_type_ascription_already_typed);
74 AssistId("add_turbo_fish", AssistKind::RefactorRewrite),
77 |builder| match ctx.config.snippet_cap {
78 Some(cap) => builder.insert_snippet(cap, ident.text_range().end(), "::<${0:_}>"),
79 None => builder.insert(ident.text_range().end(), "::<_>"),
86 use crate::tests::{check_assist, check_assist_by_label, check_assist_not_applicable};
91 fn add_turbo_fish_function() {
110 fn add_turbo_fish_after_call() {
111 cov_mark::check!(add_turbo_fish_after_call);
130 fn add_turbo_fish_method() {
136 fn make<T>(&self) -> T {}
145 fn make<T>(&self) -> T {}
155 fn add_turbo_fish_one_fish_is_enough() {
156 cov_mark::check!(add_turbo_fish_one_fish_is_enough);
157 check_assist_not_applicable(
169 fn add_turbo_fish_non_generic() {
170 cov_mark::check!(add_turbo_fish_non_generic);
171 check_assist_not_applicable(
183 fn add_type_ascription_function() {
184 check_assist_by_label(
195 let x: ${0:_} = make();
198 "Add `: _` before assignment operator",
203 fn add_type_ascription_after_call() {
204 cov_mark::check!(add_type_ascription_after_call);
205 check_assist_by_label(
216 let x: ${0:_} = make();
219 "Add `: _` before assignment operator",
224 fn add_type_ascription_method() {
225 check_assist_by_label(
230 fn make<T>(&self) -> T {}
239 fn make<T>(&self) -> T {}
242 let x: ${0:_} = S.make();
245 "Add `: _` before assignment operator",
250 fn add_type_ascription_already_typed() {
251 cov_mark::check!(add_type_ascription_already_typed);
257 let x: () = make$0();
263 let x: () = make::<${0:_}>();