noname/
lib.rs

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

noname/
lib.rs
