rance_minigrep/
lib.rs

1use std::{env, error::Error, fs};
2
3pub struct Config {
4    pub query: String,
5    pub filename: String,
6    pub case_sensitive: bool,
7}
8
9impl Config {
10    pub fn new(mut args: env::Args) -> Result<Config, &'static str> {
11        args.next();
12
13        let query = match args.next() {
14            Some(arg) => arg,
15            None => return Err("Didn't get a file name"),
16        };
17
18        let filename = match args.next() {
19            Some(arg) => arg,
20            None => return Err("Didn't get a file name"),
21        };
22
23        let case_sensitive = env::var("CASE_INSENSITIVE").is_err();
24
25        Ok(Config {
26            query,
27            filename,
28            case_sensitive,
29        })
30    }
31}
32
33pub fn run(config: Config) -> Result<(), Box<dyn Error>> {
34    let contents = fs::read_to_string(config.filename)?;
35
36    let results = if config.case_sensitive {
37        search(&config.query, &contents)
38    } else {
39        search_case_insensitive(&config.query, &contents)
40    };
41
42    for line in results {
43        println!("{}", line);
44    }
45
46    Ok(())
47}
48
49pub fn search<'a>(query: &str, contents: &'a str) -> Vec<&'a str> {
50    // let mut results = Vec::new();
51
52    // for line in contents.lines() {
53    //     if line.contains(query) {
54    //         results.push(line);
55    //     }
56    // }
57
58    // results
59    contents
60      .lines()
61      .filter(|line| line.contains(query))
62      .collect()
63}
64
65pub fn search_case_insensitive<'a>(query: &str, contents: &'a str) -> Vec<&'a str> {
66    let query = query.to_lowercase();
67    // let mut results = Vec::new();
68
69    // for line in contents.lines() {
70    //     if line.to_lowercase().contains(&query) {
71    //         results.push(line)
72    //     }
73    // }
74
75    // results
76    contents
77    .lines()
78    .filter(|line| line.to_lowercase().contains(&query))
79    .collect()
80}
81
82#[cfg(test)]
83mod tests {
84    use std::vec;
85
86    use super::*;
87
88    #[test]
89    fn one_result() {
90        let query = "duct";
91        let contents = "\
92Rust:
93safe, fast, productive
94Pick three.";
95
96        assert_eq!(vec!["safe, fast, productive"], search(query, contents));
97    }
98
99    #[test]
100    fn case_result() {
101        let query = "rUsT";
102        let contents = "\
103Rust:
104safe, fast, productive.
105Pick three.
106Trust me.";
107
108        assert_eq!(
109            vec!["Rust:", "Trust me."],
110            search_case_insensitive(query, contents)
111        );
112    }
113}
rance_minigrep/lib.rs

rance_minigrep/
lib.rs
