Jose T. - Upgraded to Null Safety as well as latest sdk

example/bin/main.dart

@@ -4,10 +4,10 @@ import 'package:diff_image/diff_image.dart';
 import 'package:image/image.dart';
 
 void main() async {
-  final FIRST_IMAGE_URL =
-      'https://raw.githubusercontent.com/nicolashahn/diffimg/master/images/mario-circle-cs.png';
-  final SECOND_IMAGE_URL =
-      'https://raw.githubusercontent.com/nicolashahn/diffimg/master/images/mario-circle-node.png';
+  final FIRST_IMAGE_URL = Uri.parse(
+      'https://raw.githubusercontent.com/nicolashahn/diffimg/master/images/mario-circle-cs.png');
+  final SECOND_IMAGE_URL = Uri.parse(
+      'https://raw.githubusercontent.com/nicolashahn/diffimg/master/images/mario-circle-node.png');
 
   // You need a try/catch block to handle the exceptions (http request, different size, etc)
   try {

lib/src/diff_image_html.dart

@@ -1,14 +1,13 @@
 import 'package:image/image.dart';
-import 'package:meta/meta.dart';
 import 'helper_functions.dart';
 import 'models/diff_img_result.dart';
 
 class DiffImage {
   /// Returns a single number representing the difference between two RGB pixels
   static num _diffBetweenPixels({
-    @required int firstPixel,
-    @required bool ignoreAlpha,
-    @required int secondPixel,
+    required int firstPixel,
+    required bool ignoreAlpha,
+    required int secondPixel,
   }) {
     var fRed = getRed(firstPixel);
     var fGreen = getGreen(firstPixel);
@@ -100,9 +99,9 @@ class DiffImage {
         secondPixel = secondImg.getPixel(i, j);
 
         diffAtPixel = _diffBetweenPixels(
-          firstPixel: firstPixel,
+          firstPixel: firstPixel.toInt(),
           ignoreAlpha: ignoreAlpha,
-          secondPixel: secondPixel,
+          secondPixel: secondPixel.toInt(),
         );
         diff += diffAtPixel;
 
@@ -112,8 +111,8 @@ class DiffImage {
           j,
           selectColor(
             diffAtPixel: diffAtPixel,
-            firstPixel: firstPixel,
-            secondPixel: secondPixel,
+            firstPixel: firstPixel.toInt(),
+            secondPixel: secondPixel.toInt(),
           ),
         );
       }
@@ -132,7 +131,7 @@ class DiffImage {
   /// Function to store an [Image] object as PNG in local storage.
   /// Not supported on web.
   static Future<void> saveDiffImg({
-    @required Image diffImg,
+    required Image diffImg,
   }) async {
     // TODO Define if can download image file or just show
     throw UnsupportedError(

lib/src/diff_image_io.dart

@@ -1,16 +1,15 @@
 import 'dart:io' as io;
 
 import 'package:image/image.dart';
-import 'package:meta/meta.dart';
 import 'helper_functions.dart';
 import 'models/diff_img_result.dart';
 
 class DiffImage {
   /// Returns a single number representing the difference between two RGB pixels
   static num _diffBetweenPixels({
-    @required int firstPixel,
-    @required bool ignoreAlpha,
-    @required int secondPixel,
+    required int firstPixel,
+    required bool ignoreAlpha,
+    required int secondPixel,
   }) {
     var fRed = getRed(firstPixel);
     var fGreen = getGreen(firstPixel);
@@ -43,8 +42,8 @@ class DiffImage {
   ///
   /// Can throw an [Exception].
   static Future<DiffImgResult> compareFromUrl(
-    dynamic firstImgSrc,
-    dynamic secondImgSrc, {
+    Uri firstImgSrc,
+    Uri secondImgSrc, {
     bool asPercentage = true,
     bool ignoreAlpha = true,
   }) async {
@@ -102,9 +101,9 @@ class DiffImage {
         secondPixel = secondImg.getPixel(i, j);
 
         diffAtPixel = _diffBetweenPixels(
-          firstPixel: firstPixel,
+          firstPixel: firstPixel.toInt(),
           ignoreAlpha: ignoreAlpha,
-          secondPixel: secondPixel,
+          secondPixel: secondPixel.toInt(),
         );
         diff += diffAtPixel;
 
@@ -114,8 +113,8 @@ class DiffImage {
           j,
           selectColor(
             diffAtPixel: diffAtPixel,
-            firstPixel: firstPixel,
-            secondPixel: secondPixel,
+            firstPixel: firstPixel.toInt(),
+            secondPixel: secondPixel.toInt(),
           ),
         );
       }
@@ -134,7 +133,7 @@ class DiffImage {
   /// Function to store an [Image] object as PNG in local storage.
   /// Not supported on web.
   static Future<void> saveDiffImg({
-    @required Image diffImg,
+    required Image diffImg,
   }) async {
     await io.File('DiffImg.png').writeAsBytes(
       encodePng(diffImg),

lib/src/helper_functions.dart

@@ -1,11 +1,10 @@
 import 'package:http/http.dart' as http;
 import 'package:image/image.dart';
-import 'package:meta/meta.dart';
 
 /// Through http get request to [imgSrc] obtains the bytes
 /// that make up an image. Can throw an [Exception].
-Future<Image> getImg({@required dynamic imgSrc}) async {
-  Image img;
+Future<Image> getImg({required Uri imgSrc}) async {
+  Image? img;
 
   var response = await http.get(imgSrc);
   if (response.statusCode != 200) {
@@ -26,8 +25,8 @@ Future<Image> getImg({@required dynamic imgSrc}) async {
 
 /// Check if [firstImg] and [secondImg] have the same width and height.
 bool haveSameSize({
-  @required Image firstImg,
-  @required Image secondImg,
+  required Image firstImg,
+  required Image secondImg,
 }) {
   return firstImg.width == secondImg.width &&
       firstImg.height == secondImg.height;
@@ -37,9 +36,9 @@ bool haveSameSize({
 /// If one of the pixels is black, the resulting color will be the
 /// other pixel but more transparent.
 int selectColor({
-  @required num diffAtPixel,
-  @required int firstPixel,
-  @required int secondPixel,
+  required num diffAtPixel,
+  required int firstPixel,
+  required int secondPixel,
 }) {
   int result;
 

lib/src/models/diff_img_result.dart

@@ -1,12 +1,11 @@
 import 'package:image/image.dart';
-import 'package:meta/meta.dart';
 
 /// Model to encapsulate the results of a difference between images
 /// query.
 class DiffImgResult {
   DiffImgResult({
-    @required this.diffImg,
-    @required this.diffValue,
+    required this.diffImg,
+    required this.diffValue,
   });
 
   final Image diffImg;

pubspec.yaml

@@ -4,14 +4,12 @@ version: 1.0.1
 homepage: https://github.com/limonadev/diff_image
 
 environment:
-  sdk: '>=2.5.0 <3.0.0'
+  sdk: ">=2.15.0 <3.0.0"
 
 dependencies:
-  http: ^0.12.2
-  image: ^2.1.18
-  meta: ^1.1.8
+  http: ^0.13.5
+  image: ^3.2.0
 #  path: ^1.6.0
 
 dev_dependencies:
-  pedantic: ^1.8.0
-  test: ^1.15.4
+  test: ^1.21.4

test/helper_test.dart

@@ -1,13 +1,12 @@
 @TestOn('vm')
 
-import 'package:test/test.dart';
-import 'package:image/image.dart';
-
 import 'package:diff_image/src/helper_functions.dart';
+import 'package:image/image.dart';
+import 'package:test/test.dart';
 
 void main() {
   group('Test for helper functions', () {
-    String flutterLogoUrl, badUrl, anotherLogoUrl;
+    late String flutterLogoUrl, badUrl, anotherLogoUrl;
 
     setUp(() {
       // A real image
@@ -22,13 +21,13 @@ void main() {
 
     test('Get image from url', () async {
       var first = await getImg(
-        imgSrc: flutterLogoUrl,
+        imgSrc: Uri.parse(flutterLogoUrl),
       );
       expect(first, isA<Image>());
       expect(
         () async {
           await getImg(
-            imgSrc: badUrl,
+            imgSrc: Uri.parse(badUrl),
           );
         },
         throwsException,
@@ -37,7 +36,7 @@ void main() {
 
     test('Compare images size', () async {
       var img1 = await getImg(
-        imgSrc: flutterLogoUrl,
+        imgSrc: Uri.parse(flutterLogoUrl),
       );
       var areEquals = haveSameSize(
         firstImg: img1,
@@ -46,7 +45,7 @@ void main() {
       expect(areEquals, isTrue);
 
       var img2 = await getImg(
-        imgSrc: anotherLogoUrl,
+        imgSrc: Uri.parse(anotherLogoUrl),
       );
       areEquals = haveSameSize(
         firstImg: img1,

test/html_test.dart

@@ -6,18 +6,18 @@ import 'package:test/test.dart';
 
 void main() {
   group('Test when dart:html is supported', () {
-    String flutterLogoUrl, dartLogoUrl, androidLogoUrl;
+    late Uri flutterLogoUrl, dartLogoUrl, androidLogoUrl;
 
     setUp(() {
       // A real image
-      flutterLogoUrl =
-          'https://seeklogo.com/images/F/flutter-logo-5086DD11C5-seeklogo.com.png';
+      flutterLogoUrl = Uri.parse(
+          'https://seeklogo.com/images/F/flutter-logo-5086DD11C5-seeklogo.com.png');
       // Image with different size with respect to flutterLogoUrl
-      dartLogoUrl =
-          'https://www.extremetech.com/wp-content/uploads/2011/10/dart-logo-banner1-348x196.jpg';
+      dartLogoUrl = Uri.parse(
+          'https://www.extremetech.com/wp-content/uploads/2011/10/dart-logo-banner1-348x196.jpg');
       // Image with the same size as flutterLogoUrl
-      androidLogoUrl =
-          'https://seeklogo.com/images/A/android-western-logo-8F117A7F00-seeklogo.com.png';
+      androidLogoUrl = Uri.parse(
+          'https://seeklogo.com/images/A/android-western-logo-8F117A7F00-seeklogo.com.png');
     });
 
     test('Compare the same image', () async {

test/io_test.dart

@@ -1,23 +1,23 @@
 @TestOn('vm')
 
-import 'package:test/test.dart';
 import 'package:diff_image/diff_image.dart';
 import 'package:diff_image/src/helper_functions.dart';
+import 'package:test/test.dart';
 
 void main() {
   group('Test when dart:io is supported', () {
-    String flutterLogoUrl, dartLogoUrl, androidLogoUrl;
+    late Uri flutterLogoUrl, dartLogoUrl, androidLogoUrl;
 
     setUp(() {
       // A real image
-      flutterLogoUrl =
-          'https://seeklogo.com/images/F/flutter-logo-5086DD11C5-seeklogo.com.png';
+      flutterLogoUrl = Uri.parse(
+          'https://seeklogo.com/images/F/flutter-logo-5086DD11C5-seeklogo.com.png');
       // Image with different size with respect to flutterLogoUrl
-      dartLogoUrl =
-          'https://www.extremetech.com/wp-content/uploads/2011/10/dart-logo-banner1-348x196.jpg';
+      dartLogoUrl = Uri.parse(
+          'https://www.extremetech.com/wp-content/uploads/2011/10/dart-logo-banner1-348x196.jpg');
       // Image with the same size as flutterLogoUrl
-      androidLogoUrl =
-          'https://seeklogo.com/images/A/android-western-logo-8F117A7F00-seeklogo.com.png';
+      androidLogoUrl = Uri.parse(
+          'https://seeklogo.com/images/A/android-western-logo-8F117A7F00-seeklogo.com.png');
     });
 
     test('Compare the same image', () async {