diff options
Diffstat (limited to 'crates/ra_assists/src/flip_eq_operands.rs')
-rw-r--r-- | crates/ra_assists/src/flip_eq_operands.rs | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/crates/ra_assists/src/flip_eq_operands.rs b/crates/ra_assists/src/flip_eq_operands.rs new file mode 100644 index 000000000..22494a7c7 --- /dev/null +++ b/crates/ra_assists/src/flip_eq_operands.rs | |||
@@ -0,0 +1,87 @@ | |||
1 | use hir::db::HirDatabase; | ||
2 | use ra_syntax::{ | ||
3 | ast::{AstNode, BinExpr, BinOp} | ||
4 | }; | ||
5 | |||
6 | use crate::{AssistCtx, Assist, AssistId}; | ||
7 | |||
8 | pub(crate) fn flip_eq_operands(mut ctx: AssistCtx<impl HirDatabase>) -> Option<Assist> { | ||
9 | let expr = ctx.node_at_offset::<BinExpr>()?; | ||
10 | let allowed_ops = [BinOp::EqualityTest, BinOp::NegatedEqualityTest]; | ||
11 | let expr_op = expr.op()?; | ||
12 | if ! allowed_ops.iter().any(|o| *o == expr_op) { | ||
13 | return None; | ||
14 | } | ||
15 | let node = expr.syntax(); | ||
16 | let prev = node.first_child()?; | ||
17 | let next = node.last_child()?; | ||
18 | ctx.add_action(AssistId("flip_eq_operands"), "flip equality operands", |edit| { | ||
19 | edit.target(node.range()); | ||
20 | edit.replace(prev.range(), next.text()); | ||
21 | edit.replace(next.range(), prev.text()); | ||
22 | }); | ||
23 | |||
24 | ctx.build() | ||
25 | } | ||
26 | |||
27 | #[cfg(test)] | ||
28 | mod tests { | ||
29 | use super::*; | ||
30 | |||
31 | use crate::helpers::{check_assist, check_assist_target}; | ||
32 | |||
33 | #[test] | ||
34 | fn flip_eq_operands_for_simple_stmt() { | ||
35 | check_assist( | ||
36 | flip_eq_operands, | ||
37 | "fn f() { let res = 1 ==<|> 2; }", | ||
38 | "fn f() { let res = 2 ==<|> 1; }", | ||
39 | ) | ||
40 | } | ||
41 | |||
42 | #[test] | ||
43 | fn flip_neq_operands_for_simple_stmt() { | ||
44 | check_assist( | ||
45 | flip_eq_operands, | ||
46 | "fn f() { let res = 1 !=<|> 2; }", | ||
47 | "fn f() { let res = 2 !=<|> 1; }", | ||
48 | ) | ||
49 | } | ||
50 | |||
51 | #[test] | ||
52 | fn flip_eq_operands_for_complex_stmt() { | ||
53 | check_assist( | ||
54 | flip_eq_operands, | ||
55 | "fn f() { let res = (1 + 1) ==<|> (2 + 2); }", | ||
56 | "fn f() { let res = (2 + 2) ==<|> (1 + 1); }", | ||
57 | ) | ||
58 | } | ||
59 | |||
60 | #[test] | ||
61 | fn flip_eq_operands_in_match_expr() { | ||
62 | check_assist( | ||
63 | flip_eq_operands, | ||
64 | r#" | ||
65 | fn dyn_eq(&self, other: &dyn Diagnostic) -> bool { | ||
66 | match other.downcast_ref::<Self>() { | ||
67 | None => false, | ||
68 | Some(it) => it ==<|> self, | ||
69 | } | ||
70 | } | ||
71 | "#, | ||
72 | r#" | ||
73 | fn dyn_eq(&self, other: &dyn Diagnostic) -> bool { | ||
74 | match other.downcast_ref::<Self>() { | ||
75 | None => false, | ||
76 | Some(it) => self ==<|> it, | ||
77 | } | ||
78 | } | ||
79 | "#, | ||
80 | ) | ||
81 | } | ||
82 | |||
83 | #[test] | ||
84 | fn flip_eq_operands_target() { | ||
85 | check_assist_target(flip_eq_operands, "fn f() { let res = 1 ==<|> 2; }", "1 == 2") | ||
86 | } | ||
87 | } | ||