crates/ide_assists/src/handlers/replace_string_with_char.rs

   1 use syntax::{ast, AstToken, SyntaxKind::STRING};
   2
   3 use crate::{AssistContext, AssistId, AssistKind, Assists};
   4
   5 // Assist: replace_string_with_char
   6 //
   7 // Replace string with char.
   8 //
   9 // ```
  10 // fn main() {
  11 //     find("{$0");
  12 // }
  13 // ```
  14 // ->
  15 // ```
  16 // fn main() {
  17 //     find('{');
  18 // }
  19 // ```
  20 pub(crate) fn replace_string_with_char(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
  21     let token = ctx.find_token_syntax_at_offset(STRING).and_then(ast::String::cast)?;
  22     let value = token.value()?;
  23     let target = token.syntax().text_range();
  24
  25     if value.chars().take(2).count() != 1 {
  26         return None;
  27     }
  28
  29     acc.add(
  30         AssistId("replace_string_with_char", AssistKind::RefactorRewrite),
  31         "Replace string with char",
  32         target,
  33         |edit| {
  34             let token_text = token.syntax().text();
  35             let inner_text = &token_text[1..token_text.len() - 1];
  36             edit.replace(token.syntax().text_range(), format!("'{}'", inner_text));
  37         },
  38     )
  39 }
  40
  41 #[cfg(test)]
  42 mod tests {
  43     use crate::tests::{check_assist, check_assist_not_applicable, check_assist_target};
  44
  45     use super::*;
  46
  47     #[test]
  48     fn replace_string_with_char_target() {
  49         check_assist_target(
  50             replace_string_with_char,
  51             r#"
  52             fn f() {
  53                 let s = "$0c";
  54             }
  55             "#,
  56             r#""c""#,
  57         );
  58     }
  59
  60     #[test]
  61     fn replace_string_with_char_assist() {
  62         check_assist(
  63             replace_string_with_char,
  64             r#"
  65     fn f() {
  66         let s = "$0c";
  67     }
  68     "#,
  69             r##"
  70     fn f() {
  71         let s = 'c';
  72     }
  73     "##,
  74         )
  75     }
  76
  77     #[test]
  78     fn replace_string_with_char_assist_with_emoji() {
  79         check_assist(
  80             replace_string_with_char,
  81             r#"
  82     fn f() {
  83         let s = "$0😀";
  84     }
  85     "#,
  86             r##"
  87     fn f() {
  88         let s = '😀';
  89     }
  90     "##,
  91         )
  92     }
  93
  94     #[test]
  95     fn replace_string_with_char_assist_not_applicable() {
  96         check_assist_not_applicable(
  97             replace_string_with_char,
  98             r#"
  99     fn f() {
 100         let s = "$0test";
 101     }
 102     "#,
 103         )
 104     }
 105
 106     #[test]
 107     fn replace_string_with_char_works_inside_macros() {
 108         check_assist(
 109             replace_string_with_char,
 110             r#"
 111                 fn f() {
 112                     format!($0"x", 92)
 113                 }
 114                 "#,
 115             r##"
 116                 fn f() {
 117                     format!('x', 92)
 118                 }
 119                 "##,
 120         )
 121     }
 122
 123     #[test]
 124     fn replace_string_with_char_works_func_args() {
 125         check_assist(
 126             replace_string_with_char,
 127             r#"
 128                 fn f() {
 129                     find($0"x");
 130                 }
 131                 "#,
 132             r##"
 133                 fn f() {
 134                     find('x');
 135                 }
 136                 "##,
 137         )
 138     }
 139
 140     #[test]
 141     fn replace_string_with_char_newline() {
 142         check_assist(
 143             replace_string_with_char,
 144             r#"
 145                 fn f() {
 146                     find($0"\n");
 147                 }
 148                 "#,
 149             r##"
 150                 fn f() {
 151                     find('\n');
 152                 }
 153                 "##,
 154         )
 155     }
 156
 157     #[test]
 158     fn replace_string_with_char_unicode_escape() {
 159         check_assist(
 160             replace_string_with_char,
 161             r#"
 162                 fn f() {
 163                     find($0"\u{7FFF}");
 164                 }
 165                 "#,
 166             r##"
 167                 fn f() {
 168                     find('\u{7FFF}');
 169                 }
 170                 "##,
 171         )
 172     }
 173 }