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pub fn encode(s: &str) -> String {
let mut e = String::with_capacity(s.len() * 3);
for c in s.chars() {
match c as u8 {
45|46|95|126|65..=90|97..=122 => {
e.push(c as char);
}
n => {
e.push_str(&format!("%{:02X}", n));
}
}
}
e
}
pub fn decode(s: &str) -> String {
s.chars().fold((String::with_capacity(s.len()), String::with_capacity(3)), |(mut a, mut b),c| {
if c == '%' || b.len() > 0 {
if c == '%' { b.clear(); }
b.push(c);
if b.len() == 3 {
match u8::from_str_radix(b.get(1..=2).unwrap_or(""), 16) {
Ok(n) => {
a.push(n as char);
}
Err(_) => {}
}
b.clear();
}
} else {
a.push(c);
}
(a,b)
}).0
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn hello_world(){
assert_eq!("hello%20world%21", encode("hello world!"));
assert_eq!("hello world!", decode("hello%20world%21"));
}
#[test]
fn long_str() {
assert_eq!("you%20are%20now%20immortal", encode("you are now immortal"));
assert_eq!("you are now immortal", decode("you%20are%20now%20immortal"));
assert_eq!("you are now immortal", decode("%79%6F%75%20%61%72%65%20%6E%6F%77%20%69%6D%6D%6F%72%74%61%6C"));
}
#[test]
fn bad_str() {
assert_eq!("", decode("%2%GG"));
assert_eq!("", decode("%2Z%GG"));
assert_eq!("", decode("%2%%"));
}
}