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