1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
|
use hir::db::HirDatabase;
use ra_syntax::{
TextUnit,
SyntaxElement,
ast::{MatchArm, AstNode, AstToken},
ast,
};
use crate::{AssistCtx, Assist, AssistId};
pub(crate) fn move_guard_to_arm_body(mut ctx: AssistCtx<impl HirDatabase>) -> Option<Assist> {
let match_arm = ctx.node_at_offset::<MatchArm>()?;
let guard = match_arm.guard()?;
let space_before_guard = guard.syntax().prev_sibling_or_token();
let guard_conditions = guard.expr()?;
let arm_expr = match_arm.expr()?;
let buf = format!("if {} {{ {} }}", guard_conditions.syntax().text(), arm_expr.syntax().text());
ctx.add_action(AssistId("move_guard_to_arm_body"), "move guard to arm body", |edit| {
edit.target(guard.syntax().range());
let offseting_amount = match space_before_guard {
Some(SyntaxElement::Token(tok)) => {
if let Some(_) = ast::Whitespace::cast(tok) {
let ele = space_before_guard.unwrap().range();
edit.delete(ele);
ele.len()
} else {
TextUnit::from(0)
}
}
_ => TextUnit::from(0),
};
edit.delete(guard.syntax().range());
edit.replace_node_and_indent(arm_expr.syntax(), buf);
edit.set_cursor(arm_expr.syntax().range().start() + TextUnit::from(3) - offseting_amount);
});
ctx.build()
}
#[cfg(test)]
mod tests {
use super::*;
use crate::helpers::{ check_assist, check_assist_target };
#[test]
fn move_guard_to_arm_body_target() {
check_assist_target(
move_guard_to_arm_body,
r#"
fn f() {
let t = 'a';
let chars = "abcd";
match t {
'\r' <|>if chars.clone().next() == Some('\n') => false,
_ => true
}
}
"#,
r#"if chars.clone().next() == Some('\n')"#,
);
}
#[test]
fn move_guard_to_arm_body_works() {
check_assist(
move_guard_to_arm_body,
r#"
fn f() {
let t = 'a';
let chars = "abcd";
match t {
'\r' <|>if chars.clone().next() == Some('\n') => false,
_ => true
}
}
"#,
r#"
fn f() {
let t = 'a';
let chars = "abcd";
match t {
'\r' => if chars.clone().next() == Some('\n') { <|>false },
_ => true
}
}
"#,
);
}
#[test]
fn move_guard_to_arm_body_works_complex_match() {
check_assist(
move_guard_to_arm_body,
r#"
fn f() {
match x {
<|>y @ 4 | y @ 5 if y > 5 => true,
_ => false
}
}
"#,
r#"
fn f() {
match x {
y @ 4 | y @ 5 => if y > 5 { <|>true },
_ => false
}
}
"#,
);
}
}
|