use std::fs;
use std::error::Error;
use std::env;
pub fn run(config:&Config)->Result<(), Box<dyn Error>> {
let contents = fs::read_to_string(&config.filename)?;
if config.case_sensitive{
for line in search(&config.query, &contents) {
println!("{}", line);
}
}
else{
for line in search_case_insensitive(&config.query, &contents) {
println!("{}", line);
}
}
Ok(())
}
pub struct Config {
pub query: String,
pub filename: String,
pub case_sensitive:bool,
}
impl Config {
pub fn new(mut args: std::env::Args)->Result<Config,&'static str>{
if args.len() < 3 {
return Err("Not enough arguement");
}
args.next();
let query = match args.next(){
Some(arg) => arg,
None => return Err("Didn't get a query string"),
};
let filename = match args.next(){
Some(arg) => arg,
None => return Err("Didn't get a query string"),
};
let case_sensitive = env::var("CASE_INSENSITIVE").is_err();
return Ok(Config { query, filename,case_sensitive })
}
}
pub fn search<'a>(query: &str, contents: &'a str) -> Vec<&'a str> {
contents.lines()
.filter(|line| line.contains(query))
.collect()
}
pub fn search_case_insensitive<'a>(query: &str,contents: &'a str) ->Vec<&'a str>{
let query = query.to_lowercase();
contents.lines()
.filter(|line| line.to_lowercase().contains(&query))
.collect()
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn case_insensitive(){
let query = "rUsT";
let contents = "\
Rust:
safe, fast, productive.
Pick three.
Trust me.";
assert_eq!(
vec!["Rust:", "Trust me."],
search_case_insensitive(query, contents)
);
}
#[test]
fn case_sensitive(){
let query = "duct";
let contents = "\
Rust:
safe, fast, productive.
Pick three.
Duct tape.";
assert_eq!(
vec!["safe, fast, productive."],
search(query, contents)
);
}
}