update dart to add integer encoding tests

Author: drinckes

dart/lib/src/open_location_code.dart

@@ -254,11 +254,6 @@ bool isFull(String code) {
 /// * [codeLength]: The number of significant digits in the output code, not
 /// including any separator characters.
 String encode(num latitude, num longitude, {int codeLength = pairCodeLength}) {
-  if (codeLength < minDigitCount ||
-      (codeLength < pairCodeLength && codeLength.isOdd)) {
-    throw ArgumentError('Invalid Open Location Code length: $codeLength');
-  }
-  codeLength = min(maxDigitCount, codeLength);
   var integers = locationToIntegers(latitude, longitude);
   return encodeIntegers(integers[0], integers[1], codeLength);
 }
@@ -293,6 +288,11 @@ List<int> locationToIntegers(num latitude, num longitude) {
 
 /// Encode a location into an Open Location Code.
 String encodeIntegers(int latVal, int lngVal, int codeLength) {
+  if (codeLength < minDigitCount ||
+      (codeLength < pairCodeLength && codeLength.isOdd)) {
+    throw ArgumentError('Invalid Open Location Code length: $codeLength');
+  }
+  codeLength = min(maxDigitCount, codeLength);
   List<String> code = List<String>.filled(maxDigitCount + 1, '');
   code[separatorPosition] = separator;
 

dart/test/encode_test.dart

@@ -18,20 +18,48 @@ import 'package:open_location_code/open_location_code.dart' as olc;
 import 'package:test/test.dart';
 import 'utils.dart';
 
-// code,lat,lng,latLo,lngLo,latHi,lngHi
-void checkEncodeDecode(String csvLine) {
+void checkEncode(String csvLine) {
   var elements = csvLine.split(',');
   num lat = double.parse(elements[0]);
   num lng = double.parse(elements[1]);
-  int len = int.parse(elements[2]);
-  var want = elements[3];
+  int lat_int = int.parse(elements[2]);
+  int lng_int = int.parse(elements[3]);
+  int len = int.parse(elements[4]);
+  var want = elements[5];
   var got = olc.encode(lat, lng, codeLength: len);
   expect(got, equals(want));
 }
 
+void checkLocationToIntegers(String csvLine) {
+  var elements = csvLine.split(',');
+  num lat = double.parse(elements[0]);
+  num lng = double.parse(elements[1]);
+  int lat_int = int.parse(elements[2]);
+  int lng_int = int.parse(elements[3]);
+  var got = olc.locationToIntegers(lat, lng);
+  expect(got[0], equals(lat_int));
+  expect(got[1], equals(lng_int));
+}
+
+void checkEncodeIntegers(String csvLine) {
+  var elements = csvLine.split(',');
+  int lat_int = int.parse(elements[2]);
+  int lng_int = int.parse(elements[3]);
+  int len = int.parse(elements[4]);
+  var want = elements[5];
+  var got = olc.encodeIntegers(lat_int, lng_int, len);
+  expect(got, equals(want));
+}
+
 void main() {
-  test('Check encode decode', () {
-    csvLinesFromFile('encoding.csv').forEach(checkEncodeDecode);
+  test('Check encode', () {
+    csvLinesFromFile('encoding.csv').forEach(checkEncode);
+  });
+  test('Check locationToIntegers', () {
+    csvLinesFromFile('encoding.csv').forEach(checkLocationToIntegers);
+  });
+  test('Check encodeIntegers', () {
+    csvLinesFromFile('encoding.csv').forEach(checkEncodeIntegers);
   });
 
   test('MaxCodeLength', () {