graphql_parser/query/
minify.rs

1use crate::tokenizer::{Kind, Token, TokenStream};
2use combine::StreamOnce;
3use thiserror::Error;
4
5/// Error minifying query
6#[derive(Error, Debug)]
7#[error("query minify error: {}", _0)]
8pub struct MinifyError(String);
9
10pub fn minify_query(source: String) -> Result<String, MinifyError> {
11    let mut bits: Vec<&str> = Vec::new();
12    let mut stream = TokenStream::new(source.as_str());
13    let mut prev_was_punctuator = false;
14
15    loop {
16        match stream.uncons() {
17            Ok(x) => {
18                let token: Token = x;
19                let is_non_punctuator = token.kind != Kind::Punctuator;
20
21                if prev_was_punctuator && is_non_punctuator {
22                    bits.push(" ");
23                }
24
25                bits.push(token.value);
26                prev_was_punctuator = is_non_punctuator;
27            }
28            Err(ref e) if e == &combine::easy::Error::end_of_input() => break,
29            Err(e) => return Err(MinifyError(e.to_string())),
30        }
31    }
32
33    Ok(bits.join(""))
34}
35
36#[cfg(test)]
37mod tests {
38    #[test]
39    fn strip_ignored_characters() {
40        let source = "
41        query SomeQuery($foo: String!, $bar: String) {
42            someField(foo: $foo, bar: $bar) {
43                a
44                b { 
45                    ... on B {
46                        c 
47                        d 
48                    } 
49                } 
50            } 
51        }
52        ";
53
54        let minified = super::minify_query(source.to_string()).expect("minification failed");
55
56        assert_eq!(
57            &minified,
58            "query SomeQuery($foo:String!$bar:String){someField(foo:$foo bar:$bar){a b{...on B{c d}}}}"
59        );
60    }
61
62    #[test]
63    fn unexpected_token() {
64        let source = "
65        query foo {
66            bar;
67        }
68        ";
69
70        let minified = super::minify_query(source.to_string());
71
72        assert!(minified.is_err());
73
74        assert_eq!(
75            minified.unwrap_err().to_string(),
76            "query minify error: Unexpected unexpected character ';'"
77        );
78    }
79}
graphql_parser/query/minify.rs

graphql_parser/query/
minify.rs
