parsers: Bump base64

Version 0.21 replaced base64::decode() with an Engine trait and multiple
structs implementing it for various alphabets, various performance
profiles, etc.  It is slightly longer to import but in the end does the
very same thing.

parsers/src/hashes.rs

@@ -6,6 +6,7 @@
 
 use crate::util::error::Error;
 use crate::util::helpers::Base64;
+use base64::{engine::general_purpose::STANDARD as Base64Engine, Engine};
 use minidom::IntoAttributeValue;
 use std::num::ParseIntError;
 use std::ops::{Deref, DerefMut};
@@ -117,7 +118,7 @@ impl Hash {
     /// Like [new](#method.new) but takes base64-encoded data before decoding
     /// it.
     pub fn from_base64(algo: Algo, hash: &str) -> Result<Hash, Error> {
-        Ok(Hash::new(algo, base64::decode(hash)?))
+        Ok(Hash::new(algo, Base64Engine.decode(hash)?))
     }
 
     /// Like [new](#method.new) but takes hex-encoded data before decoding it.
@@ -145,7 +146,7 @@ impl Hash {
 
     /// Formats this hash into base64.
     pub fn to_base64(&self) -> String {
-        base64::encode(&self.hash[..])
+        Base64Engine.encode(&self.hash[..])
     }
 
     /// Formats this hash into hexadecimal.
@@ -227,7 +228,9 @@ mod tests {
         assert_eq!(hash.algo, Algo::Sha_256);
         assert_eq!(
             hash.hash,
-            base64::decode("2XarmwTlNxDAMkvymloX3S5+VbylNrJt/l5QyPa+YoU=").unwrap()
+            Base64Engine
+                .decode("2XarmwTlNxDAMkvymloX3S5+VbylNrJt/l5QyPa+YoU=")
+                .unwrap()
         );
     }