ide_completion/completions/postfix/
format_like.rs

1// Feature: Format String Completion
2//
3// `"Result {result} is {2 + 2}"` is expanded to the `"Result {} is {}", result, 2 + 2`.
4//
5// The following postfix snippets are available:
6//
7// * `format` -> `format!(...)`
8// * `panic` -> `panic!(...)`
9// * `println` -> `println!(...)`
10// * `log`:
11// ** `logd` -> `log::debug!(...)`
12// ** `logt` -> `log::trace!(...)`
13// ** `logi` -> `log::info!(...)`
14// ** `logw` -> `log::warn!(...)`
15// ** `loge` -> `log::error!(...)`
16//
17// ![Format String Completion](https://user-images.githubusercontent.com/48062697/113020656-b560f500-917a-11eb-87de-02991f61beb8.gif)
18
19use ide_db::{
20    SnippetCap,
21    source_change::SnippetEdit,
22    syntax_helpers::format_string_exprs::{Arg, parse_format_exprs, with_placeholders},
23};
24use syntax::{AstToken, ast};
25
26use crate::{
27    Completions, completions::postfix::build_postfix_snippet_builder, context::CompletionContext,
28};
29
30/// Mapping ("postfix completion item" => "macro to use")
31static KINDS: &[(&str, &str)] = &[
32    ("format", "format!"),
33    ("panic", "panic!"),
34    ("println", "println!"),
35    ("eprintln", "eprintln!"),
36    ("logd", "log::debug!"),
37    ("logt", "log::trace!"),
38    ("logi", "log::info!"),
39    ("logw", "log::warn!"),
40    ("loge", "log::error!"),
41];
42static SNIPPET_RETURNS_NON_UNIT: &[&str] = &["format"];
43
44pub(crate) fn add_format_like_completions(
45    acc: &mut Completions,
46    ctx: &CompletionContext<'_, '_>,
47    dot_receiver: &ast::Expr,
48    cap: SnippetCap,
49    receiver_text: &ast::String,
50    semi: &str,
51) {
52    let postfix_snippet = match build_postfix_snippet_builder(ctx, cap, dot_receiver) {
53        Some(it) => it,
54        None => return,
55    };
56
57    if let Ok((mut out, mut exprs)) = parse_format_exprs(receiver_text.text()) {
58        // Escape any snippet bits in the out text and any of the exprs.
59        SnippetEdit::escape_snippet_bits(&mut out);
60        for arg in &mut exprs {
61            if let Arg::Ident(text) | Arg::Expr(text) = arg {
62                SnippetEdit::escape_snippet_bits(text)
63            }
64        }
65
66        let exprs = with_placeholders(exprs);
67        for (label, macro_name) in KINDS {
68            let semi = if SNIPPET_RETURNS_NON_UNIT.contains(label) { "" } else { semi };
69            let snippet = if exprs.is_empty() {
70                format!(r#"{macro_name}({out}){semi}"#)
71            } else {
72                format!(r#"{}({}, {}){semi}"#, macro_name, out, exprs.join(", "))
73            };
74
75            postfix_snippet(label, macro_name, snippet).add_to(acc, ctx.db);
76        }
77    }
78}
79
80#[cfg(test)]
81mod tests {
82    use super::*;
83
84    #[test]
85    fn test_into_suggestion() {
86        let test_vector = &[
87            ("println!", "{}", r#"println!("{}", $1)"#),
88            ("eprintln!", "{}", r#"eprintln!("{}", $1)"#),
89            (
90                "log::info!",
91                "{} {ident} {} {2 + 2}",
92                r#"log::info!("{} {ident} {} {}", $1, $2, 2 + 2)"#,
93            ),
94        ];
95
96        for (kind, input, output) in test_vector {
97            let (parsed_string, exprs) = parse_format_exprs(input).unwrap();
98            let exprs = with_placeholders(exprs);
99            let snippet = format!(r#"{kind}("{parsed_string}", {})"#, exprs.join(", "));
100            assert_eq!(&snippet, output);
101        }
102    }
103
104    #[test]
105    fn test_into_suggestion_no_epxrs() {
106        let test_vector = &[
107            ("println!", "{ident}", r#"println!("{ident}")"#),
108            ("format!", "{ident:?}", r#"format!("{ident:?}")"#),
109        ];
110
111        for (kind, input, output) in test_vector {
112            let (parsed_string, _exprs) = parse_format_exprs(input).unwrap();
113            let snippet = format!(r#"{kind}("{parsed_string}")"#);
114            assert_eq!(&snippet, output);
115        }
116    }
117}
ide_completion/completions/postfix/format_like.rs

ide_completion/completions/postfix/
format_like.rs
