diff options
Diffstat (limited to 'crates/ide_diagnostics/src/handlers/missing_ok_or_some_in_tail_expr.rs')
-rw-r--r-- | crates/ide_diagnostics/src/handlers/missing_ok_or_some_in_tail_expr.rs | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/crates/ide_diagnostics/src/handlers/missing_ok_or_some_in_tail_expr.rs b/crates/ide_diagnostics/src/handlers/missing_ok_or_some_in_tail_expr.rs new file mode 100644 index 000000000..63de54570 --- /dev/null +++ b/crates/ide_diagnostics/src/handlers/missing_ok_or_some_in_tail_expr.rs | |||
@@ -0,0 +1,229 @@ | |||
1 | use hir::db::AstDatabase; | ||
2 | use ide_db::{assists::Assist, source_change::SourceChange}; | ||
3 | use syntax::AstNode; | ||
4 | use text_edit::TextEdit; | ||
5 | |||
6 | use crate::{fix, Diagnostic, DiagnosticsContext}; | ||
7 | |||
8 | // Diagnostic: missing-ok-or-some-in-tail-expr | ||
9 | // | ||
10 | // This diagnostic is triggered if a block that should return `Result` returns a value not wrapped in `Ok`, | ||
11 | // or if a block that should return `Option` returns a value not wrapped in `Some`. | ||
12 | // | ||
13 | // Example: | ||
14 | // | ||
15 | // ```rust | ||
16 | // fn foo() -> Result<u8, ()> { | ||
17 | // 10 | ||
18 | // } | ||
19 | // ``` | ||
20 | pub(crate) fn missing_ok_or_some_in_tail_expr( | ||
21 | ctx: &DiagnosticsContext<'_>, | ||
22 | d: &hir::MissingOkOrSomeInTailExpr, | ||
23 | ) -> Diagnostic { | ||
24 | Diagnostic::new( | ||
25 | "missing-ok-or-some-in-tail-expr", | ||
26 | format!("wrap return expression in {}", d.required), | ||
27 | ctx.sema.diagnostics_display_range(d.expr.clone().map(|it| it.into())).range, | ||
28 | ) | ||
29 | .with_fixes(fixes(ctx, d)) | ||
30 | } | ||
31 | |||
32 | fn fixes(ctx: &DiagnosticsContext<'_>, d: &hir::MissingOkOrSomeInTailExpr) -> Option<Vec<Assist>> { | ||
33 | let root = ctx.sema.db.parse_or_expand(d.expr.file_id)?; | ||
34 | let tail_expr = d.expr.value.to_node(&root); | ||
35 | let tail_expr_range = tail_expr.syntax().text_range(); | ||
36 | let replacement = format!("{}({})", d.required, tail_expr.syntax()); | ||
37 | let edit = TextEdit::replace(tail_expr_range, replacement); | ||
38 | let source_change = | ||
39 | SourceChange::from_text_edit(d.expr.file_id.original_file(ctx.sema.db), edit); | ||
40 | let name = if d.required == "Ok" { "Wrap with Ok" } else { "Wrap with Some" }; | ||
41 | Some(vec![fix("wrap_tail_expr", name, source_change, tail_expr_range)]) | ||
42 | } | ||
43 | |||
44 | #[cfg(test)] | ||
45 | mod tests { | ||
46 | use crate::tests::{check_diagnostics, check_fix}; | ||
47 | |||
48 | #[test] | ||
49 | fn test_wrap_return_type_option() { | ||
50 | check_fix( | ||
51 | r#" | ||
52 | //- /main.rs crate:main deps:core | ||
53 | use core::option::Option::{self, Some, None}; | ||
54 | |||
55 | fn div(x: i32, y: i32) -> Option<i32> { | ||
56 | if y == 0 { | ||
57 | return None; | ||
58 | } | ||
59 | x / y$0 | ||
60 | } | ||
61 | //- /core/lib.rs crate:core | ||
62 | pub mod result { | ||
63 | pub enum Result<T, E> { Ok(T), Err(E) } | ||
64 | } | ||
65 | pub mod option { | ||
66 | pub enum Option<T> { Some(T), None } | ||
67 | } | ||
68 | "#, | ||
69 | r#" | ||
70 | use core::option::Option::{self, Some, None}; | ||
71 | |||
72 | fn div(x: i32, y: i32) -> Option<i32> { | ||
73 | if y == 0 { | ||
74 | return None; | ||
75 | } | ||
76 | Some(x / y) | ||
77 | } | ||
78 | "#, | ||
79 | ); | ||
80 | } | ||
81 | |||
82 | #[test] | ||
83 | fn test_wrap_return_type() { | ||
84 | check_fix( | ||
85 | r#" | ||
86 | //- /main.rs crate:main deps:core | ||
87 | use core::result::Result::{self, Ok, Err}; | ||
88 | |||
89 | fn div(x: i32, y: i32) -> Result<i32, ()> { | ||
90 | if y == 0 { | ||
91 | return Err(()); | ||
92 | } | ||
93 | x / y$0 | ||
94 | } | ||
95 | //- /core/lib.rs crate:core | ||
96 | pub mod result { | ||
97 | pub enum Result<T, E> { Ok(T), Err(E) } | ||
98 | } | ||
99 | pub mod option { | ||
100 | pub enum Option<T> { Some(T), None } | ||
101 | } | ||
102 | "#, | ||
103 | r#" | ||
104 | use core::result::Result::{self, Ok, Err}; | ||
105 | |||
106 | fn div(x: i32, y: i32) -> Result<i32, ()> { | ||
107 | if y == 0 { | ||
108 | return Err(()); | ||
109 | } | ||
110 | Ok(x / y) | ||
111 | } | ||
112 | "#, | ||
113 | ); | ||
114 | } | ||
115 | |||
116 | #[test] | ||
117 | fn test_wrap_return_type_handles_generic_functions() { | ||
118 | check_fix( | ||
119 | r#" | ||
120 | //- /main.rs crate:main deps:core | ||
121 | use core::result::Result::{self, Ok, Err}; | ||
122 | |||
123 | fn div<T>(x: T) -> Result<T, i32> { | ||
124 | if x == 0 { | ||
125 | return Err(7); | ||
126 | } | ||
127 | $0x | ||
128 | } | ||
129 | //- /core/lib.rs crate:core | ||
130 | pub mod result { | ||
131 | pub enum Result<T, E> { Ok(T), Err(E) } | ||
132 | } | ||
133 | pub mod option { | ||
134 | pub enum Option<T> { Some(T), None } | ||
135 | } | ||
136 | "#, | ||
137 | r#" | ||
138 | use core::result::Result::{self, Ok, Err}; | ||
139 | |||
140 | fn div<T>(x: T) -> Result<T, i32> { | ||
141 | if x == 0 { | ||
142 | return Err(7); | ||
143 | } | ||
144 | Ok(x) | ||
145 | } | ||
146 | "#, | ||
147 | ); | ||
148 | } | ||
149 | |||
150 | #[test] | ||
151 | fn test_wrap_return_type_handles_type_aliases() { | ||
152 | check_fix( | ||
153 | r#" | ||
154 | //- /main.rs crate:main deps:core | ||
155 | use core::result::Result::{self, Ok, Err}; | ||
156 | |||
157 | type MyResult<T> = Result<T, ()>; | ||
158 | |||
159 | fn div(x: i32, y: i32) -> MyResult<i32> { | ||
160 | if y == 0 { | ||
161 | return Err(()); | ||
162 | } | ||
163 | x $0/ y | ||
164 | } | ||
165 | //- /core/lib.rs crate:core | ||
166 | pub mod result { | ||
167 | pub enum Result<T, E> { Ok(T), Err(E) } | ||
168 | } | ||
169 | pub mod option { | ||
170 | pub enum Option<T> { Some(T), None } | ||
171 | } | ||
172 | "#, | ||
173 | r#" | ||
174 | use core::result::Result::{self, Ok, Err}; | ||
175 | |||
176 | type MyResult<T> = Result<T, ()>; | ||
177 | |||
178 | fn div(x: i32, y: i32) -> MyResult<i32> { | ||
179 | if y == 0 { | ||
180 | return Err(()); | ||
181 | } | ||
182 | Ok(x / y) | ||
183 | } | ||
184 | "#, | ||
185 | ); | ||
186 | } | ||
187 | |||
188 | #[test] | ||
189 | fn test_wrap_return_type_not_applicable_when_expr_type_does_not_match_ok_type() { | ||
190 | check_diagnostics( | ||
191 | r#" | ||
192 | //- /main.rs crate:main deps:core | ||
193 | use core::result::Result::{self, Ok, Err}; | ||
194 | |||
195 | fn foo() -> Result<(), i32> { 0 } | ||
196 | |||
197 | //- /core/lib.rs crate:core | ||
198 | pub mod result { | ||
199 | pub enum Result<T, E> { Ok(T), Err(E) } | ||
200 | } | ||
201 | pub mod option { | ||
202 | pub enum Option<T> { Some(T), None } | ||
203 | } | ||
204 | "#, | ||
205 | ); | ||
206 | } | ||
207 | |||
208 | #[test] | ||
209 | fn test_wrap_return_type_not_applicable_when_return_type_is_not_result_or_option() { | ||
210 | check_diagnostics( | ||
211 | r#" | ||
212 | //- /main.rs crate:main deps:core | ||
213 | use core::result::Result::{self, Ok, Err}; | ||
214 | |||
215 | enum SomeOtherEnum { Ok(i32), Err(String) } | ||
216 | |||
217 | fn foo() -> SomeOtherEnum { 0 } | ||
218 | |||
219 | //- /core/lib.rs crate:core | ||
220 | pub mod result { | ||
221 | pub enum Result<T, E> { Ok(T), Err(E) } | ||
222 | } | ||
223 | pub mod option { | ||
224 | pub enum Option<T> { Some(T), None } | ||
225 | } | ||
226 | "#, | ||
227 | ); | ||
228 | } | ||
229 | } | ||