Test PaginatedDataTable (#7594)

This patch contains some basic tests for PaginatedDataTable.

packages/flutter/lib/src/material/paginated_data_table.dart

@@ -84,8 +84,11 @@ class PaginatedDataTable extends StatefulWidget {
     assert(sortAscending != null);
     assert(rowsPerPage != null);
     assert(rowsPerPage > 0);
-    assert(availableRowsPerPage != null);
-    assert(availableRowsPerPage.contains(rowsPerPage));
+    assert(() {
+      if (onRowsPerPageChanged != null)
+        assert(availableRowsPerPage != null && availableRowsPerPage.contains(rowsPerPage));
+      return true;
+    });
     assert(source != null);
   }
 
@@ -346,6 +349,7 @@ class PaginatedDataTableState extends State<PaginatedDataTable> {
       new IconButton(
         icon: new Icon(Icons.chevron_left),
         padding: EdgeInsets.zero,
+        tooltip: 'Previous page',
         onPressed: _firstRowIndex <= 0 ? null : () {
           pageTo(math.max(_firstRowIndex - config.rowsPerPage, 0));
         }
@@ -354,6 +358,7 @@ class PaginatedDataTableState extends State<PaginatedDataTable> {
       new IconButton(
         icon: new Icon(Icons.chevron_right),
         padding: EdgeInsets.zero,
+        tooltip: 'Next page',
         onPressed: (!_rowCountApproximate && (_firstRowIndex + config.rowsPerPage >= _rowCount)) ? null : () {
           pageTo(_firstRowIndex + config.rowsPerPage);
         }
@@ -363,7 +368,8 @@ class PaginatedDataTableState extends State<PaginatedDataTable> {
 
     // CARD
     return new Card(
-      child: new BlockBody(
+      child: new Column(
+        crossAxisAlignment: CrossAxisAlignment.stretch,
         children: <Widget>[
           new DefaultTextStyle(
             // These typographic styles aren't quite the regular ones. We pick the closest ones from the regular

packages/flutter/test/material/paginated_data_table_test.dart

+// Copyright 2017 The Chromium Authors. 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_test/flutter_test.dart';
+
+import 'data_table_test.dart' show Dessert, kDesserts;
+
+class TestDataSource extends DataTableSource {
+  int get generation => _generation;
+  int _generation = 0;
+  set generation(int value) {
+    if (_generation == value)
+      return;
+    _generation = value;
+    notifyListeners();
+  }
+
+  @override
+  DataRow getRow(int index) {
+    final Dessert dessert = kDesserts[index % kDesserts.length];
+    final int page = index ~/ kDesserts.length;
+    return new DataRow.byIndex(
+      index: index,
+      cells: <DataCell>[
+        new DataCell(new Text('${dessert.name} ($page)')),
+        new DataCell(new Text('${dessert.calories}')),
+        new DataCell(new Text('$generation')),
+      ],
+    );
+  }
+
+  @override
+  int get rowCount => 500 * kDesserts.length;
+
+  @override
+  bool get isRowCountApproximate => false;
+
+  @override
+  int get selectedRowCount => 0;
+}
+
+void main() {
+  testWidgets('PaginatedDataTable control test', (WidgetTester tester) async {
+    TestDataSource source = new TestDataSource()
+      ..generation = 42;
+
+    List<String> log = <String>[];
+
+    Widget buildTable(TestDataSource source) {
+      return new PaginatedDataTable(
+        header: new Text('Test table'),
+        source: source,
+        onPageChanged: (int rowIndex) {
+          log.add('page-changed: $rowIndex');
+        },
+        columns: <DataColumn>[
+          new DataColumn(
+            label: new Text('Name'),
+            tooltip: 'Name',
+          ),
+          new DataColumn(
+            label: new Text('Calories'),
+            tooltip: 'Calories',
+            numeric: true,
+            onSort: (int columnIndex, bool ascending) {
+              log.add('column-sort: $columnIndex $ascending');
+            }
+          ),
+          new DataColumn(
+            label: new Text('Generation'),
+            tooltip: 'Generation',
+          ),
+        ],
+        actions: <Widget>[
+          new IconButton(
+            icon: new Icon(Icons.adjust),
+            onPressed: () {
+              log.add('action: adjust');
+            },
+          ),
+        ],
+      );
+    }
+
+    await tester.pumpWidget(new MaterialApp(
+      home: buildTable(source),
+    ));
+
+    expect(find.text('Gingerbread (0)'), findsOneWidget);
+    expect(find.text('Gingerbread (1)'), findsNothing);
+    expect(find.text('42'), findsNWidgets(10));
+
+    source.generation = 43;
+    await tester.pump();
+
+    expect(find.text('42'), findsNothing);
+    expect(find.text('43'), findsNWidgets(10));
+
+    source = new TestDataSource()
+      ..generation = 15;
+
+    await tester.pumpWidget(new MaterialApp(
+      home: buildTable(source),
+    ));
+
+    expect(find.text('42'), findsNothing);
+    expect(find.text('43'), findsNothing);
+    expect(find.text('15'), findsNWidgets(10));
+
+    PaginatedDataTableState state = tester.state(find.byType(PaginatedDataTable));
+
+    expect(log, isEmpty);
+    state.pageTo(23);
+    expect(log, <String>['page-changed: 20']);
+    log.clear();
+
+    await tester.pump();
+
+    expect(find.text('Gingerbread (0)'), findsNothing);
+    expect(find.text('Gingerbread (1)'), findsNothing);
+    expect(find.text('Gingerbread (2)'), findsOneWidget);
+
+    await tester.tap(find.icon(Icons.adjust));
+    expect(log, <String>['action: adjust']);
+    log.clear();
+  });
+
+  testWidgets('PaginatedDataTable paging', (WidgetTester tester) async {
+    TestDataSource source = new TestDataSource();
+
+    List<String> log = <String>[];
+
+    await tester.pumpWidget(new MaterialApp(
+      home: new PaginatedDataTable(
+        header: new Text('Test table'),
+        source: source,
+        rowsPerPage: 2,
+        availableRowsPerPage: <int>[
+          2, 4, 8, 16,
+        ],
+        onRowsPerPageChanged: (int rowsPerPage) {
+          log.add('rows-per-page-changed: $rowsPerPage');
+        },
+        onPageChanged: (int rowIndex) {
+          log.add('page-changed: $rowIndex');
+        },
+        columns: <DataColumn>[
+          new DataColumn(label: new Text('Name')),
+          new DataColumn(label: new Text('Calories'), numeric: true),
+          new DataColumn(label: new Text('Generation')),
+        ],
+      )
+    ));
+
+    await tester.tap(find.byTooltip('Next page'));
+
+    expect(log, <String>['page-changed: 2']);
+    log.clear();
+
+    await tester.pump();
+
+    expect(find.text('Frozen yogurt (0)'), findsNothing);
+    expect(find.text('Eclair (0)'), findsOneWidget);
+    expect(find.text('Gingerbread (0)'), findsNothing);
+
+    await tester.tap(find.icon(Icons.chevron_left));
+
+    expect(log, <String>['page-changed: 0']);
+    log.clear();
+
+    await tester.pump();
+
+    expect(find.text('Frozen yogurt (0)'), findsOneWidget);
+    expect(find.text('Eclair (0)'), findsNothing);
+    expect(find.text('Gingerbread (0)'), findsNothing);
+
+    await tester.tap(find.icon(Icons.chevron_left));
+
+    expect(log, isEmpty);
+
+    await tester.tap(find.text('2'));
+    await tester.pumpUntilNoTransientCallbacks(const Duration(milliseconds: 200));
+
+    await tester.tap(find.text('8').last);
+    await tester.pumpUntilNoTransientCallbacks(const Duration(milliseconds: 200));
+
+    expect(log, <String>['rows-per-page-changed: 8']);
+    log.clear();
+  });
+}

packages/flutter_test/lib/src/finders.dart

@@ -32,6 +32,17 @@ class CommonFinders {
   /// nodes that are [Offstage] or that are from inactive [Route]s.
   Finder text(String text, { bool skipOffstage: true }) => new _TextFinder(text, skipOffstage: skipOffstage);
 
+  /// Finds [Icon] widgets containing icon data equal to the `icon`
+  /// argument.
+  ///
+  /// Example:
+  ///
+  ///     expect(tester, hasWidget(find.icon(Icons.chevron_left)));
+  ///
+  /// If the `skipOffstage` argument is true (the default), then this skips
+  /// nodes that are [Offstage] or that are from inactive [Route]s.
+  Finder icon(IconData icon, { bool skipOffstage: true }) => new _IconFinder(icon, skipOffstage: skipOffstage);
+
   /// Looks for widgets that contain a [Text] descendant with `text`
   /// in it.
   ///
@@ -318,6 +329,23 @@ class _TextFinder extends MatchFinder {
   }
 }
 
+class _IconFinder extends MatchFinder {
+  _IconFinder(this.icon, { bool skipOffstage: true }) : super(skipOffstage: skipOffstage);
+
+  final IconData icon;
+
+  @override
+  String get description => 'icon "$icon"';
+
+  @override
+  bool matches(Element candidate) {
+    if (candidate.widget is! Icon)
+      return false;
+    Icon iconWidget = candidate.widget;
+    return iconWidget.icon == icon;
+  }
+}
+
 class _WidgetWithTextFinder extends Finder {
   _WidgetWithTextFinder(this.widgetType, this.text, { bool skipOffstage: true }) : super(skipOffstage: skipOffstage);