Remove clap validator + add max-filesize integration tests

src/app.rs

@@ -1,7 +1,6 @@
 use std::collections::HashMap;
 
 use clap::{App, AppSettings, Arg, ArgSettings};
-use regex::Regex;
 
 const ABOUT: &'static str = "
 ripgrep (rg) recursively searches your current directory for a regex pattern.
@@ -147,8 +146,7 @@ fn app<F>(next_line_help: bool, doc: F) -> App<'static, 'static>
              .short("m").value_name("NUM").takes_value(true)
              .validator(validate_number))
         .arg(flag("max-filesize")
-             .value_name("NUM+SUFFIX?").takes_value(true)
-             .validator(validate_max_filesize))
+             .value_name("NUM+SUFFIX?").takes_value(true))
         .arg(flag("maxdepth")
              .value_name("NUM").takes_value(true)
              .validator(validate_number))
@@ -502,24 +500,3 @@ lazy_static! {
 fn validate_number(s: String) -> Result<(), String> {
     s.parse::<usize>().map(|_|()).map_err(|err| err.to_string())
 }
-
-fn validate_max_filesize(s: String) -> Result<(), String> {
-    let re = Regex::new(r#"^(\d+)([KMG])?$"#).unwrap();
-    let caps = try!(re.captures(&s)
-                      .ok_or("invalid format for max-filesize argument"));
-
-    let value = caps.get(1);
-    let suffix = caps.get(2).map(|x| x.as_str());
-
-    match value {
-        Some(value) => {
-            try!(value.as_str().parse::<u64>().map_err(|err| err.to_string()));
-        }
-        None => ()
-    }
-
-    match suffix {
-        None | Some("K") | Some("M") | Some("G") => Ok(()),
-        _ => Err(From::from("invalid suffix for max-filesize argument"))
-    }
-}