Function minigrep_xyp::search_case_insensitive

pub fn search_case_insensitive<'a>(
    query: &str, 
    contents: &'a str
) -> Vec<&'a str>

search a query in the contents, and return the matched lines. This function is case insensitive.

example

let query = "rUst";
let contents = "\
rust, Python, Java,
Rust, Ruby, Trust.
Oops.
";
assert_eq!(
   minigrep_xyp::search_case_insensitive(query, contents),
   vec!["rust, Python, Java,", "Rust, Ruby, Trust."]
);