2 algo::non_trivia_sibling,
7 use crate::{AssistContext, AssistId, AssistKind, Assists};
9 // Assist: flip_trait_bound
11 // Flips two trait bounds.
14 // fn foo<T: Clone +$0 Copy>() { }
18 // fn foo<T: Copy + Clone>() { }
20 pub(crate) fn flip_trait_bound(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<()> {
21 // We want to replicate the behavior of `flip_binexpr` by only suggesting
22 // the assist when the cursor is on a `+`
23 let plus = ctx.find_token_syntax_at_offset(T![+])?;
25 // Make sure we're in a `TypeBoundList`
26 if ast::TypeBoundList::cast(plus.parent()?).is_none() {
30 let (before, after) = (
31 non_trivia_sibling(plus.clone().into(), Direction::Prev)?,
32 non_trivia_sibling(plus.clone().into(), Direction::Next)?,
35 let target = plus.text_range();
37 AssistId("flip_trait_bound", AssistKind::RefactorRewrite),
41 edit.replace(before.text_range(), after.to_string());
42 edit.replace(after.text_range(), before.to_string());
51 use crate::tests::{check_assist, check_assist_not_applicable, check_assist_target};
54 fn flip_trait_bound_assist_available() {
55 check_assist_target(flip_trait_bound, "struct S<T> where T: A $0+ B + C { }", "+")
59 fn flip_trait_bound_not_applicable_for_single_trait_bound() {
60 check_assist_not_applicable(flip_trait_bound, "struct S<T> where T: $0A { }")
64 fn flip_trait_bound_works_for_struct() {
67 "struct S<T> where T: A $0+ B { }",
68 "struct S<T> where T: B + A { }",
73 fn flip_trait_bound_works_for_trait_impl() {
76 "impl X for S<T> where T: A +$0 B { }",
77 "impl X for S<T> where T: B + A { }",
82 fn flip_trait_bound_works_for_fn() {
83 check_assist(flip_trait_bound, "fn f<T: A $0+ B>(t: T) { }", "fn f<T: B + A>(t: T) { }")
87 fn flip_trait_bound_works_for_fn_where_clause() {
90 "fn f<T>(t: T) where T: A +$0 B { }",
91 "fn f<T>(t: T) where T: B + A { }",
96 fn flip_trait_bound_works_for_lifetime() {
99 "fn f<T>(t: T) where T: A $0+ 'static { }",
100 "fn f<T>(t: T) where T: 'static + A { }",
105 fn flip_trait_bound_works_for_complex_bounds() {
108 "struct S<T> where T: A<T> $0+ b_mod::B<T> + C<T> { }",
109 "struct S<T> where T: b_mod::B<T> + A<T> + C<T> { }",
114 fn flip_trait_bound_works_for_long_bounds() {
117 "struct S<T> where T: A + B + C + D + E + F +$0 G + H + I + J { }",
118 "struct S<T> where T: A + B + C + D + E + G + F + H + I + J { }",