revert encoding 'fix' and add unit test.

veilid-flutter/lib/veilid_encoding.dart

@@ -13,17 +13,12 @@ String base64UrlNoPadEncode(List<int> bytes) {
 }
 
 Uint8List base64UrlNoPadDecode(String source) {
-  if(source.length % 4 != 0) {
-    source = base64.normalize(source);
-  }
-  return base64.decode(source);
+  source = base64Url.normalize(source);
+  return base64Url.decode(source);
 }
 
-Uint8List base64UrlNoPadDecodeDynamic(dynamic source) {
-  source = source as String;
-  source = base64.normalize(source);
-  return base64.decode(source);
-}
+Uint8List base64UrlNoPadDecodeDynamic(dynamic source) =>
+    base64UrlNoPadDecode(source as String);
 
 class Uint8ListJsonConverter implements JsonConverter<Uint8List, String> {
   const Uint8ListJsonConverter();
@@ -36,7 +31,6 @@ class Uint8ListJsonConverter implements JsonConverter<Uint8List, String> {
 
 @immutable
 abstract class EncodedString extends Equatable {
-
   const EncodedString(String s) : contents = s;
   final String contents;
   @override
@@ -76,7 +70,6 @@ abstract class EncodedString extends Equatable {
 
 @immutable
 class FixedEncodedString32 extends EncodedString {
-
   factory FixedEncodedString32.fromBytes(Uint8List bytes) {
     if (bytes.length != decodedLength()) {
       throw Exception('length ${bytes.length} should be ${decodedLength()}');
@@ -103,7 +96,6 @@ class FixedEncodedString32 extends EncodedString {
 
 @immutable
 class FixedEncodedString43 extends EncodedString {
-
   factory FixedEncodedString43.fromBytes(Uint8List bytes) {
     if (bytes.length != decodedLength()) {
       throw Exception('length ${bytes.length} should be ${decodedLength()}');
@@ -130,7 +122,6 @@ class FixedEncodedString43 extends EncodedString {
 
 @immutable
 class FixedEncodedString86 extends EncodedString {
-
   factory FixedEncodedString86.fromBytes(Uint8List bytes) {
     if (bytes.length != decodedLength()) {
       throw Exception('length ${bytes.length} should be ${decodedLength()}');

veilid-flutter/test/test_encoding.dart

@@ -0,0 +1,70 @@
+import 'dart:convert';
+import 'dart:math';
+import 'dart:typed_data';
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:veilid/veilid_encoding.dart';
+
+const knownVectors = [
+  ['', ''],
+  ['f', 'Zg'],
+  ['fo', 'Zm8'],
+  ['foo', 'Zm9v'],
+  ['foob', 'Zm9vYg'],
+  ['fooba', 'Zm9vYmE'],
+  ['foobar', 'Zm9vYmFy']
+];
+
+Future<void> _testEncodingKnownVector(Uint8List k, String v) async {
+  final e = base64UrlNoPadEncode(k);
+  expect(e, v, reason: 'encode mismatch');
+
+  final d = base64UrlNoPadDecode(v);
+  expect(d, k, reason: 'decode mismatch');
+
+  final r = base64UrlNoPadDecode(e);
+  expect(r, k, reason: 'round trip mismatch');
+}
+
+Future<void> testEncodingKnownVectors() async {
+  for (final kv in knownVectors) {
+    final k = Uint8List.fromList(kv[0].codeUnits);
+    final v = kv[1];
+
+    await _testEncodingKnownVector(k, v);
+  }
+}
+
+Future<void> testEncodeDecodeGarbage() async {
+  final random = Random(0);
+  for (var n = 0; n < 8192; n++) {
+    final kl = List<int>.empty(growable: true);
+    for (var p = 0; p < n; p++) {
+      final v = random.nextInt(256);
+      kl.add(v);
+    }
+    final k = Uint8List.fromList(kl);
+
+    final e = base64UrlNoPadEncode(k);
+    final r = base64UrlNoPadDecode(e);
+
+    expect(r, k, reason: 'garbage round trip mismatch');
+  }
+}
+
+Future<void> testEncodeDecodeGarbagePad() async {
+  final random = Random(0);
+  for (var n = 0; n < 8192; n++) {
+    final kl = List<int>.empty(growable: true);
+    for (var p = 0; p < n; p++) {
+      final v = random.nextInt(256);
+      kl.add(v);
+    }
+    final k = Uint8List.fromList(kl);
+
+    final e = base64Url.encode(k);
+    final r = base64UrlNoPadDecode(e);
+
+    expect(r, k, reason: 'garbage w/pad round trip mismatch');
+  }
+}

veilid-flutter/test/veilid_test.dart

@@ -1,16 +1,14 @@
 import 'package:flutter_test/flutter_test.dart';
-import 'package:veilid/veilid.dart';
+import 'test_encoding.dart';
 
 void main() {
-  final api = Veilid.instance;
-
   TestWidgetsFlutterBinding.ensureInitialized();
 
   setUp(() {});
 
   tearDown(() {});
 
-  test('veilidVersionString', () async {
-    expect(api.veilidVersionString(), '0.1.0');
-  });
+  test('testEncodingKnownVectors', testEncodingKnownVectors);
+  test('testEncodeDecodeGarbage', testEncodeDecodeGarbage);
+  test('testEncodeDecodeGarbagePad', testEncodeDecodeGarbagePad);
 }