dialog picker test

lib/screens/metering/components/shared/readings_container/components/shared/animated_dialog_picker/components/dialog_picker/widget_picker_dialog.dart

@@ -118,7 +118,11 @@ class _DialogPickerState<T> extends State<DialogPicker<T>> {
               ),
               const SizedBox(width: Dimens.grid16),
               TextButton(
-                onPressed: () => widget.onSelect(_selectedValue),
+                onPressed: () {
+                  if (widget.initialValue != _selectedValue) {
+                    widget.onSelect(_selectedValue);
+                  }
+                },
                 child: Text(S.of(context).select),
               ),
             ],

test/screens/metering/components/shared/readings_container/shared/dialog_picker_test.dart

@@ -0,0 +1,89 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:lightmeter/generated/l10n.dart';
+import 'package:lightmeter/res/dimens.dart';
+import 'package:lightmeter/screens/metering/components/shared/readings_container/components/iso_picker/widget_picker_iso.dart';
+import 'package:lightmeter/screens/metering/components/shared/readings_container/components/shared/animated_dialog_picker/components/dialog_picker/widget_picker_dialog.dart';
+import 'package:m3_lightmeter_resources/m3_lightmeter_resources.dart';
+import 'package:mocktail/mocktail.dart';
+
+import '../../../../../../application_mock.dart';
+
+class _ValueChanged {
+  void onChanged<T>(T value) {}
+}
+
+class _MockValueChanged extends Mock implements _ValueChanged {}
+
+void main() {
+  final functions = _MockValueChanged();
+
+  group(
+    'onChanged',
+    () {
+      testWidgets(
+        'other',
+        (tester) async {
+          await tester.pumpApplication(functions.onChanged);
+          await tester.openAnimatedPicker<IsoValuePicker>();
+          expect(find.byType(DialogPicker<IsoValue>), findsOneWidget);
+          await tester.tapListTile(500);
+          await tester.tapSelectButton();
+          verify(() => functions.onChanged(const IsoValue(500, StopType.third))).called(1);
+        },
+      );
+
+      testWidgets(
+        'same',
+        (tester) async {
+          await tester.pumpApplication(functions.onChanged);
+          await tester.openAnimatedPicker<IsoValuePicker>();
+          expect(find.byType(DialogPicker<IsoValue>), findsOneWidget);
+          await tester.tapListTile(400);
+          await tester.tapSelectButton();
+          verifyNever(() => functions.onChanged(const IsoValue(400, StopType.full)));
+        },
+      );
+    },
+  );
+}
+
+extension WidgetTesterActions on WidgetTester {
+  Future<void> pumpApplication(ValueChanged<IsoValue> onChanged) async {
+    await pumpWidget(
+      WidgetTestApplicationMock(
+        child: Row(
+          children: [
+            Expanded(
+              child: IsoValuePicker(
+                selectedValue: const IsoValue(400, StopType.full),
+                values: IsoValue.values,
+                onChanged: onChanged,
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+    await pumpAndSettle();
+  }
+
+  Future<void> openAnimatedPicker<T>() async {
+    await tap(find.byType(T));
+    await pumpAndSettle(Dimens.durationL);
+  }
+
+  Future<void> tapListTile(int iso) async {
+    expect(find.descendant(of: find.byType(RadioListTile<IsoValue>), matching: find.text('$iso')), findsOneWidget);
+    await tap(find.descendant(of: find.byType(RadioListTile<IsoValue>), matching: find.text('$iso')));
+  }
+
+  Future<void> tapSelectButton() async {
+    final cancelButton = find.byWidgetPredicate(
+      (widget) => widget is TextButton && widget.child is Text && (widget.child as Text?)?.data == S.current.select,
+    );
+    expect(cancelButton, findsOneWidget);
+    await tap(cancelButton);
+    await pumpAndSettle();
+  }
+}