aboutsummaryrefslogtreecommitdiff
path: root/crates/ide/src/typing
diff options
context:
space:
mode:
Diffstat (limited to 'crates/ide/src/typing')
-rw-r--r--crates/ide/src/typing/on_enter.rs256
1 files changed, 256 insertions, 0 deletions
diff --git a/crates/ide/src/typing/on_enter.rs b/crates/ide/src/typing/on_enter.rs
new file mode 100644
index 000000000..f7d46146c
--- /dev/null
+++ b/crates/ide/src/typing/on_enter.rs
@@ -0,0 +1,256 @@
1//! Handles the `Enter` key press. At the momently, this only continues
2//! comments, but should handle indent some time in the future as well.
3
4use base_db::{FilePosition, SourceDatabase};
5use ide_db::RootDatabase;
6use syntax::{
7 ast::{self, AstToken},
8 AstNode, SmolStr, SourceFile,
9 SyntaxKind::*,
10 SyntaxToken, TextRange, TextSize, TokenAtOffset,
11};
12use test_utils::mark;
13use text_edit::TextEdit;
14
15// Feature: On Enter
16//
17// rust-analyzer can override kbd:[Enter] key to make it smarter:
18//
19// - kbd:[Enter] inside triple-slash comments automatically inserts `///`
20// - kbd:[Enter] in the middle or after a trailing space in `//` inserts `//`
21//
22// This action needs to be assigned to shortcut explicitly.
23//
24// VS Code::
25//
26// Add the following to `keybindings.json`:
27// [source,json]
28// ----
29// {
30// "key": "Enter",
31// "command": "rust-analyzer.onEnter",
32// "when": "editorTextFocus && !suggestWidgetVisible && editorLangId == rust"
33// }
34// ----
35pub(crate) fn on_enter(db: &RootDatabase, position: FilePosition) -> Option<TextEdit> {
36 let parse = db.parse(position.file_id);
37 let file = parse.tree();
38 let comment = file
39 .syntax()
40 .token_at_offset(position.offset)
41 .left_biased()
42 .and_then(ast::Comment::cast)?;
43
44 if comment.kind().shape.is_block() {
45 return None;
46 }
47
48 let prefix = comment.prefix();
49 let comment_range = comment.syntax().text_range();
50 if position.offset < comment_range.start() + TextSize::of(prefix) {
51 return None;
52 }
53
54 let mut remove_last_space = false;
55 // Continuing single-line non-doc comments (like this one :) ) is annoying
56 if prefix == "//" && comment_range.end() == position.offset {
57 if comment.text().ends_with(' ') {
58 mark::hit!(continues_end_of_line_comment_with_space);
59 remove_last_space = true;
60 } else if !followed_by_comment(&comment) {
61 return None;
62 }
63 }
64
65 let indent = node_indent(&file, comment.syntax())?;
66 let inserted = format!("\n{}{} $0", indent, prefix);
67 let delete = if remove_last_space {
68 TextRange::new(position.offset - TextSize::of(' '), position.offset)
69 } else {
70 TextRange::empty(position.offset)
71 };
72 let edit = TextEdit::replace(delete, inserted);
73 Some(edit)
74}
75
76fn followed_by_comment(comment: &ast::Comment) -> bool {
77 let ws = match comment.syntax().next_token().and_then(ast::Whitespace::cast) {
78 Some(it) => it,
79 None => return false,
80 };
81 if ws.spans_multiple_lines() {
82 return false;
83 }
84 ws.syntax().next_token().and_then(ast::Comment::cast).is_some()
85}
86
87fn node_indent(file: &SourceFile, token: &SyntaxToken) -> Option<SmolStr> {
88 let ws = match file.syntax().token_at_offset(token.text_range().start()) {
89 TokenAtOffset::Between(l, r) => {
90 assert!(r == *token);
91 l
92 }
93 TokenAtOffset::Single(n) => {
94 assert!(n == *token);
95 return Some("".into());
96 }
97 TokenAtOffset::None => unreachable!(),
98 };
99 if ws.kind() != WHITESPACE {
100 return None;
101 }
102 let text = ws.text();
103 let pos = text.rfind('\n').map(|it| it + 1).unwrap_or(0);
104 Some(text[pos..].into())
105}
106
107#[cfg(test)]
108mod tests {
109 use stdx::trim_indent;
110 use test_utils::{assert_eq_text, mark};
111
112 use crate::mock_analysis::analysis_and_position;
113
114 fn apply_on_enter(before: &str) -> Option<String> {
115 let (analysis, position) = analysis_and_position(&before);
116 let result = analysis.on_enter(position).unwrap()?;
117
118 let mut actual = analysis.file_text(position.file_id).unwrap().to_string();
119 result.apply(&mut actual);
120 Some(actual)
121 }
122
123 fn do_check(ra_fixture_before: &str, ra_fixture_after: &str) {
124 let ra_fixture_after = &trim_indent(ra_fixture_after);
125 let actual = apply_on_enter(ra_fixture_before).unwrap();
126 assert_eq_text!(ra_fixture_after, &actual);
127 }
128
129 fn do_check_noop(ra_fixture_text: &str) {
130 assert!(apply_on_enter(ra_fixture_text).is_none())
131 }
132
133 #[test]
134 fn continues_doc_comment() {
135 do_check(
136 r"
137/// Some docs<|>
138fn foo() {
139}
140",
141 r"
142/// Some docs
143/// $0
144fn foo() {
145}
146",
147 );
148
149 do_check(
150 r"
151impl S {
152 /// Some<|> docs.
153 fn foo() {}
154}
155",
156 r"
157impl S {
158 /// Some
159 /// $0 docs.
160 fn foo() {}
161}
162",
163 );
164
165 do_check(
166 r"
167///<|> Some docs
168fn foo() {
169}
170",
171 r"
172///
173/// $0 Some docs
174fn foo() {
175}
176",
177 );
178 }
179
180 #[test]
181 fn does_not_continue_before_doc_comment() {
182 do_check_noop(r"<|>//! docz");
183 }
184
185 #[test]
186 fn continues_code_comment_in_the_middle_of_line() {
187 do_check(
188 r"
189fn main() {
190 // Fix<|> me
191 let x = 1 + 1;
192}
193",
194 r"
195fn main() {
196 // Fix
197 // $0 me
198 let x = 1 + 1;
199}
200",
201 );
202 }
203
204 #[test]
205 fn continues_code_comment_in_the_middle_several_lines() {
206 do_check(
207 r"
208fn main() {
209 // Fix<|>
210 // me
211 let x = 1 + 1;
212}
213",
214 r"
215fn main() {
216 // Fix
217 // $0
218 // me
219 let x = 1 + 1;
220}
221",
222 );
223 }
224
225 #[test]
226 fn does_not_continue_end_of_line_comment() {
227 do_check_noop(
228 r"
229fn main() {
230 // Fix me<|>
231 let x = 1 + 1;
232}
233",
234 );
235 }
236
237 #[test]
238 fn continues_end_of_line_comment_with_space() {
239 mark::check!(continues_end_of_line_comment_with_space);
240 do_check(
241 r#"
242fn main() {
243 // Fix me <|>
244 let x = 1 + 1;
245}
246"#,
247 r#"
248fn main() {
249 // Fix me
250 // $0
251 let x = 1 + 1;
252}
253"#,
254 );
255 }
256}