fix base64url and add percent convenience

Author: tanner0101

Sources/Bits/Base64Encoder.swift

@@ -26,10 +26,22 @@ public final class Base64Encoder {
                 return nil
             }
         }
-
+        
+        let decodeMap: Base64Encoder.ByteMap = { byte in
+            switch byte {
+            case Byte.hyphen:
+                return 62
+            case Byte.underscore:
+                return 63
+            default:
+                return nil
+            }
+        }
+        
         return Base64Encoder(
             padding: nil,
-            encodeMap: encodeMap
+            encodeMap: encodeMap,
+            decodeMap: decodeMap
         )
     }
 

Sources/Bits/Bytes+Base64.swift

@@ -1,5 +1,3 @@
-import Foundation
-
 extension Sequence where Iterator.Element == Byte {
     public var base64Encoded: Bytes {
         let bytes = Array(self)

Sources/Bits/Bytes+Percent.swift

@@ -0,0 +1,33 @@
+import Foundation
+
+extension Sequence where Iterator.Element == Byte {
+    public var percentDecoded: Bytes {
+        return makeString()
+            .removingPercentEncoding?
+            .makeBytes() ?? []
+    }
+    
+    public var percentEncodedForURLQuery: Bytes {
+        return makeString()
+            .addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed)?
+            .makeBytes() ?? []
+    }
+    
+    public var percentEncodedForURLPath: Bytes {
+        return makeString()
+            .addingPercentEncoding(withAllowedCharacters: .urlPathAllowed)?
+            .makeBytes() ?? []
+    }
+    
+    public var percentEncodedForURLHost: Bytes {
+        return makeString()
+            .addingPercentEncoding(withAllowedCharacters: .urlHostAllowed)?
+            .makeBytes() ?? []
+    }
+    
+    public var percentEncodedForURLFragment: Bytes {
+        return makeString()
+            .addingPercentEncoding(withAllowedCharacters: .urlFragmentAllowed)?
+            .makeBytes() ?? []
+    }
+}

Tests/BitsTests/ByteTests.swift

@@ -153,4 +153,10 @@ class ByteTests: XCTestCase {
             "aa"
         )
     }
+    
+    public func testBase64URLDecodeJWT() {
+        let jwt = "Aw_Ma0impeGEaCQn6AramTZ6hXeW0bJm_3dKbiXtJDOBhs1Zm6IgX-uJhuzW0SY2evWL4D2ZX5I90ISAzEdabw".makeBytes()
+        let decoded = jwt.base64URLDecoded
+        XCTAssertEqual(decoded.count, 64)
+    }
 }