Added tests for image widgets

packages/zefyr/test/widgets/buttons_test.dart

@@ -152,7 +152,7 @@ void main() {
     setUp(() {
       channel.setMockMethodCallHandler((MethodCall methodCall) async {
         log.add(methodCall);
-        return 'file:///tmp/test.jpg';
+        return '/tmp/test.jpg';
       });
       log.clear();
     });

packages/zefyr/test/widgets/image_test.dart

@@ -0,0 +1,110 @@
+// Copyright (c) 2018, the Zefyr project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:image_picker/image_picker.dart';
+import 'package:zefyr/zefyr.dart';
+
+import '../testing.dart';
+
+void main() {
+  group('$ZefyrDefaultImageDelegate', () {
+    const MethodChannel channel =
+        const MethodChannel('plugins.flutter.io/image_picker');
+
+    final List<MethodCall> log = <MethodCall>[];
+
+    setUp(() {
+      channel.setMockMethodCallHandler((MethodCall methodCall) async {
+        log.add(methodCall);
+        return '/tmp/test.jpg';
+      });
+      log.clear();
+    });
+
+    test('pick image', () async {
+      final delegate = new ZefyrDefaultImageDelegate();
+      final result = await delegate.pickImage(ImageSource.gallery);
+      expect(result, 'file:///tmp/test.jpg');
+    });
+  });
+
+  group('$ZefyrImage', () {
+    const MethodChannel channel =
+        const MethodChannel('plugins.flutter.io/image_picker');
+
+    final List<MethodCall> log = <MethodCall>[];
+
+    setUp(() {
+      channel.setMockMethodCallHandler((MethodCall methodCall) async {
+        log.add(methodCall);
+        return '/tmp/test.jpg';
+      });
+      log.clear();
+    });
+
+    testWidgets('embed image', (tester) async {
+      final editor = new EditorSandBox(tester: tester);
+      await editor.tapEditor();
+      await editor.tapButtonWithIcon(Icons.photo);
+      await editor.tapButtonWithIcon(Icons.photo_camera);
+      LineNode line = editor.document.root.children.last;
+      expect(line.hasEmbed, isTrue);
+      EmbedNode embed = line.children.single;
+      expect(embed.style.value(NotusAttribute.embed), <String, dynamic>{
+        'type': 'image',
+        'source': 'file:///tmp/test.jpg',
+      });
+      expect(find.byType(ZefyrImage), findsOneWidget);
+    });
+
+    testWidgets('tap on left side of image puts caret before it',
+        (tester) async {
+      final editor = new EditorSandBox(tester: tester);
+      await editor.tapEditor();
+      await editor.tapButtonWithIcon(Icons.photo);
+      await editor.tapButtonWithIcon(Icons.photo_camera);
+      await editor.updateSelection(base: 0, extent: 0);
+
+      await tester.tapAt(tester.getTopLeft(find.byType(ZefyrImage)));
+      LineNode line = editor.document.root.children.last;
+      EmbedNode embed = line.children.single;
+      expect(editor.selection.isCollapsed, isTrue);
+      expect(editor.selection.extentOffset, embed.documentOffset);
+    });
+
+    testWidgets('tap right side of horizontal rule puts caret after it',
+        (tester) async {
+      final editor = new EditorSandBox(tester: tester);
+      await editor.tapEditor();
+      await editor.tapButtonWithIcon(Icons.photo);
+      await editor.tapButtonWithIcon(Icons.photo_camera);
+      await editor.updateSelection(base: 0, extent: 0);
+
+      final img = find.byType(ZefyrImage);
+      final offset = tester.getBottomRight(img) - new Offset(1.0, 1.0);
+      await tester.tapAt(offset);
+      LineNode line = editor.document.root.children.last;
+      EmbedNode embed = line.children.single;
+      expect(editor.selection.isCollapsed, isTrue);
+      expect(editor.selection.extentOffset, embed.documentOffset + 1);
+    });
+
+    testWidgets('selects on long press', (tester) async {
+      final editor = new EditorSandBox(tester: tester);
+      await editor.tapEditor();
+      await editor.tapButtonWithIcon(Icons.photo);
+      await editor.tapButtonWithIcon(Icons.photo_camera);
+      await editor.updateSelection(base: 0, extent: 0);
+
+      final img = find.byType(ZefyrImage);
+      await tester.longPress(img);
+      LineNode line = editor.document.root.children.last;
+      EmbedNode embed = line.children.single;
+      expect(editor.selection.baseOffset, embed.documentOffset);
+      expect(editor.selection.extentOffset, embed.documentOffset + 1);
+    });
+  });
+}