minigrep_carlossgv/
lib.rs1use std::{env, error::Error, fs};
2
3pub struct Config {
4 pub query: String,
5 pub file_path: String,
6 pub ignore_case: bool,
7}
8
9impl Config {
10 pub fn build(mut args: impl Iterator<Item = String>) -> 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 query string"),
16 };
17
18 let file_path = match args.next() {
19 Some(arg) => arg,
20 None => return Err("Didn't get a file path"),
21 };
22
23 let ignore_case = env::var("IGNORE_CASE").is_ok();
24
25 Ok(Config {
26 query,
27 file_path,
28 ignore_case,
29 })
30 }
31}
32
33pub fn run(config: Config) -> Result<(), Box<dyn Error>> {
34 let contents = fs::read_to_string(config.file_path)?;
35
36 let results = if config.ignore_case {
37 search_case_insensitive(&config.query, &contents)
38 } else {
39 search(&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 contents
51 .lines()
52 .filter(|line| line.contains(query))
53 .collect()
54}
55
56pub fn search_case_insensitive<'a>(query: &str, contents: &'a str) -> Vec<&'a str> {
66 contents
67 .lines()
68 .filter(|line| line.to_lowercase().contains(&query.to_lowercase()))
69 .collect()
70}
71
72#[cfg(test)]
73mod tests {
74 use super::*;
75
76 #[test]
77 fn one_result() {
78 let query = "duct";
79 let contents = "\
80Rust:
81safe, fast, productive.
82Pick three.
83Duct tape.";
84
85 assert_eq!(vec!["safe, fast, productive."], search(query, contents));
86 }
87
88 #[test]
89 fn case_insensitive() {
90 let query = "rUsT";
91 let contents = "\
92Rust:
93safe, fast, productive.
94Pick three.
95Trust me.";
96
97 assert_eq!(
98 vec!["Rust:", "Trust me."],
99 search_case_insensitive(query, contents)
100 );
101 }
102}