src/tools/rust-analyzer/crates/ide-assists/src/handlers/replace_string_with_char.rs

   1 use syntax::{
   2     ast,
   3     ast::IsString,
   4     AstToken,
   5     SyntaxKind::{CHAR, STRING},
   6     TextRange, TextSize,
   7 };
   8
   9 use crate::{AssistContext, AssistId, AssistKind, Assists};
  10
  11 // Assist: replace_string_with_char
  12 //
  13 // Replace string literal with char literal.
  14 //
  15 // ```
  16 // fn main() {
  17 //     find("{$0");
  18 // }
  19 // ```
  20 // ->
  21 // ```
  22 // fn main() {
  23 //     find('{');
  24 // }
  25 // ```
  26 pub(crate) fn replace_string_with_char(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<()> {
  27     let token = ctx.find_token_syntax_at_offset(STRING).and_then(ast::String::cast)?;
  28     let value = token.value()?;
  29     let target = token.syntax().text_range();
  30
  31     if value.chars().take(2).count() != 1 {
  32         return None;
  33     }
  34     let quote_offets = token.quote_offsets()?;
  35
  36     acc.add(
  37         AssistId("replace_string_with_char", AssistKind::RefactorRewrite),
  38         "Replace string with char",
  39         target,
  40         |edit| {
  41             let (left, right) = quote_offets.quotes;
  42             edit.replace(left, '\'');
  43             edit.replace(right, '\'');
  44             if value == "'" {
  45                 edit.insert(left.end(), '\\');
  46             }
  47         },
  48     )
  49 }
  50
  51 // Assist: replace_char_with_string
  52 //
  53 // Replace a char literal with a string literal.
  54 //
  55 // ```
  56 // fn main() {
  57 //     find('{$0');
  58 // }
  59 // ```
  60 // ->
  61 // ```
  62 // fn main() {
  63 //     find("{");
  64 // }
  65 // ```
  66 pub(crate) fn replace_char_with_string(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<()> {
  67     let token = ctx.find_token_syntax_at_offset(CHAR)?;
  68     let target = token.text_range();
  69
  70     acc.add(
  71         AssistId("replace_char_with_string", AssistKind::RefactorRewrite),
  72         "Replace char with string",
  73         target,
  74         |edit| {
  75             if token.text() == "'\"'" {
  76                 edit.replace(token.text_range(), r#""\"""#);
  77             } else {
  78                 let len = TextSize::of('\'');
  79                 edit.replace(TextRange::at(target.start(), len), '"');
  80                 edit.replace(TextRange::at(target.end() - len, len), '"');
  81             }
  82         },
  83     )
  84 }
  85
  86 #[cfg(test)]
  87 mod tests {
  88     use crate::tests::{check_assist, check_assist_not_applicable};
  89
  90     use super::*;
  91
  92     #[test]
  93     fn replace_string_with_char_assist() {
  94         check_assist(
  95             replace_string_with_char,
  96             r#"
  97 fn f() {
  98     let s = "$0c";
  99 }
 100 "#,
 101             r##"
 102 fn f() {
 103     let s = 'c';
 104 }
 105 "##,
 106         )
 107     }
 108
 109     #[test]
 110     fn replace_string_with_char_assist_with_multi_byte_char() {
 111         check_assist(
 112             replace_string_with_char,
 113             r#"
 114 fn f() {
 115     let s = "$0😀";
 116 }
 117 "#,
 118             r##"
 119 fn f() {
 120     let s = '😀';
 121 }
 122 "##,
 123         )
 124     }
 125
 126     #[test]
 127     fn replace_string_with_char_multiple_chars() {
 128         check_assist_not_applicable(
 129             replace_string_with_char,
 130             r#"
 131 fn f() {
 132     let s = "$0test";
 133 }
 134 "#,
 135         )
 136     }
 137
 138     #[test]
 139     fn replace_string_with_char_works_inside_macros() {
 140         check_assist(
 141             replace_string_with_char,
 142             r#"
 143 fn f() {
 144     format!($0"x", 92)
 145 }
 146 "#,
 147             r##"
 148 fn f() {
 149     format!('x', 92)
 150 }
 151 "##,
 152         )
 153     }
 154
 155     #[test]
 156     fn replace_string_with_char_newline() {
 157         check_assist(
 158             replace_string_with_char,
 159             r#"
 160 fn f() {
 161     find($0"\n");
 162 }
 163 "#,
 164             r##"
 165 fn f() {
 166     find('\n');
 167 }
 168 "##,
 169         )
 170     }
 171
 172     #[test]
 173     fn replace_string_with_char_unicode_escape() {
 174         check_assist(
 175             replace_string_with_char,
 176             r#"
 177 fn f() {
 178     find($0"\u{7FFF}");
 179 }
 180 "#,
 181             r##"
 182 fn f() {
 183     find('\u{7FFF}');
 184 }
 185 "##,
 186         )
 187     }
 188
 189     #[test]
 190     fn replace_raw_string_with_char() {
 191         check_assist(
 192             replace_string_with_char,
 193             r##"
 194 fn f() {
 195     $0r#"X"#
 196 }
 197 "##,
 198             r##"
 199 fn f() {
 200     'X'
 201 }
 202 "##,
 203         )
 204     }
 205
 206     #[test]
 207     fn replace_char_with_string_assist() {
 208         check_assist(
 209             replace_char_with_string,
 210             r"
 211 fn f() {
 212     let s = '$0c';
 213 }
 214 ",
 215             r#"
 216 fn f() {
 217     let s = "c";
 218 }
 219 "#,
 220         )
 221     }
 222
 223     #[test]
 224     fn replace_char_with_string_assist_with_multi_byte_char() {
 225         check_assist(
 226             replace_char_with_string,
 227             r"
 228 fn f() {
 229     let s = '$0😀';
 230 }
 231 ",
 232             r#"
 233 fn f() {
 234     let s = "😀";
 235 }
 236 "#,
 237         )
 238     }
 239
 240     #[test]
 241     fn replace_char_with_string_newline() {
 242         check_assist(
 243             replace_char_with_string,
 244             r"
 245 fn f() {
 246     find($0'\n');
 247 }
 248 ",
 249             r#"
 250 fn f() {
 251     find("\n");
 252 }
 253 "#,
 254         )
 255     }
 256
 257     #[test]
 258     fn replace_char_with_string_unicode_escape() {
 259         check_assist(
 260             replace_char_with_string,
 261             r"
 262 fn f() {
 263     find($0'\u{7FFF}');
 264 }
 265 ",
 266             r#"
 267 fn f() {
 268     find("\u{7FFF}");
 269 }
 270 "#,
 271         )
 272     }
 273
 274     #[test]
 275     fn replace_char_with_string_quote() {
 276         check_assist(
 277             replace_char_with_string,
 278             r#"
 279 fn f() {
 280     find($0'"');
 281 }
 282 "#,
 283             r#"
 284 fn f() {
 285     find("\"");
 286 }
 287 "#,
 288         )
 289     }
 290
 291     #[test]
 292     fn replace_string_with_char_quote() {
 293         check_assist(
 294             replace_string_with_char,
 295             r#"
 296 fn f() {
 297     find($0"'");
 298 }
 299 "#,
 300             r#"
 301 fn f() {
 302     find('\'');
 303 }
 304 "#,
 305         )
 306     }
 307 }