table.spec.ts

import {async, ComponentFixture, TestBed} from '@angular/core/testing';
import {Component, ViewChild} from '@angular/core';
import {CdkTable} from './table';
import {CollectionViewer, DataSource} from './data-source';
import {BehaviorSubject} from 'rxjs/BehaviorSubject';
import {Observable} from 'rxjs/Observable';
import {combineLatest} from 'rxjs/observable/combineLatest';
import {CdkTableModule} from './index';
import {map} from 'rxjs/operator/map';
import {getTableDuplicateColumnNameError, getTableUnknownColumnError} from './table-errors';

describe('CdkTable', () => {
  let fixture: ComponentFixture<SimpleCdkTableApp>;

  let component: SimpleCdkTableApp;
  let dataSource: FakeDataSource;
  let table: CdkTable<any>;
  let tableElement: HTMLElement;

  beforeEach(async(() => {
    TestBed.configureTestingModule({
      imports: [CdkTableModule],
      declarations: [
        SimpleCdkTableApp,
        DynamicDataSourceCdkTableApp,
        CustomRoleCdkTableApp,
        TrackByCdkTableApp,
        DynamicColumnDefinitionsCdkTableApp,
        RowContextCdkTableApp,
        DuplicateColumnDefNameCdkTableApp,
        MissingColumnDefCdkTableApp,
      ],
    }).compileComponents();
  }));

  beforeEach(() => {
    fixture = TestBed.createComponent(SimpleCdkTableApp);

    component = fixture.componentInstance;
    dataSource = component.dataSource as FakeDataSource;
    table = component.table;
    tableElement = fixture.nativeElement.querySelector('cdk-table');

    fixture.detectChanges();
  });

  describe('should initialize', () => {
    it('with a connected data source', () => {
      expect(table.dataSource).toBe(dataSource);
      expect(dataSource.isConnected).toBe(true);
    });

    it('with a rendered header with the right number of header cells', () => {
      const header = getHeaderRow(tableElement);

      expect(header).not.toBe(undefined);
      expect(header.classList).toContain('customHeaderRowClass');
      expect(getHeaderCells(tableElement).length).toBe(component.columnsToRender.length);
    });

    it('with rendered rows with right number of row cells', () => {
      const rows = getRows(tableElement);

      expect(rows.length).toBe(dataSource.data.length);
      rows.forEach(row => {
        expect(row.classList).toContain('customRowClass');
        expect(getCells(row).length).toBe(component.columnsToRender.length);
      });
    });

    it('with column class names provided to header and data row cells', () => {
      getHeaderCells(tableElement).forEach((headerCell, index) => {
        expect(headerCell.classList).toContain(`cdk-column-${component.columnsToRender[index]}`);
      });

      getRows(tableElement).forEach(row => {
        getCells(row).forEach((cell, index) => {
          expect(cell.classList).toContain(`cdk-column-${component.columnsToRender[index]}`);
        });
      });
    });

    it('with the right accessibility roles', () => {
      expect(tableElement.getAttribute('role')).toBe('grid');

      expect(getHeaderRow(tableElement).getAttribute('role')).toBe('row');
      getHeaderCells(tableElement).forEach(cell => {
        expect(cell.getAttribute('role')).toBe('columnheader');
      });

      getRows(tableElement).forEach(row => {
        expect(row.getAttribute('role')).toBe('row');
        getCells(row).forEach(cell => {
          expect(cell.getAttribute('role')).toBe('gridcell');
        });
      });
    });
  });

  it('should disconnect the data source when table is destroyed', () => {
    expect(dataSource.isConnected).toBe(true);

    fixture.destroy();
    expect(dataSource.isConnected).toBe(false);
  });

  it('should not clobber an existing table role', () => {
    fixture = TestBed.createComponent(CustomRoleCdkTableApp);
    fixture.detectChanges();

    expect(fixture.nativeElement.querySelector('cdk-table').getAttribute('role')).toBe('treegrid');
  });

  it('should throw an error if two column definitions have the same name', () => {
    expect(() => TestBed.createComponent(DuplicateColumnDefNameCdkTableApp).detectChanges())
        .toThrowError(getTableDuplicateColumnNameError('column_a').message);
  });

  it('should throw an error if a column definition is requested but not defined', () => {
    expect(() => TestBed.createComponent(MissingColumnDefCdkTableApp).detectChanges())
        .toThrowError(getTableUnknownColumnError('column_a').message);
  });

  it('should be able to dynamically add/remove column definitions', () => {
    const dynamicColumnDefFixture = TestBed.createComponent(DynamicColumnDefinitionsCdkTableApp);
    dynamicColumnDefFixture.detectChanges();
    dynamicColumnDefFixture.detectChanges();

    const dynamicColumnDefTable = dynamicColumnDefFixture.nativeElement.querySelector('cdk-table');
    const dynamicColumnDefComp = dynamicColumnDefFixture.componentInstance;

    // Add a new column and expect it to show up in the table
    let columnA = 'columnA';
    dynamicColumnDefComp.dynamicColumns.push(columnA);
    dynamicColumnDefFixture.detectChanges();
    expectTableToMatchContent(dynamicColumnDefTable, [
      [columnA], // Header row
      [columnA], // Data rows
      [columnA],
      [columnA],
    ]);

    // Add another new column and expect it to show up in the table
    let columnB = 'columnB';
    dynamicColumnDefComp.dynamicColumns.push(columnB);
    dynamicColumnDefFixture.detectChanges();
    expectTableToMatchContent(dynamicColumnDefTable, [
      [columnA, columnB], // Header row
      [columnA, columnB], // Data rows
      [columnA, columnB],
      [columnA, columnB],
    ]);

    // Remove column A expect only column B to be rendered
    dynamicColumnDefComp.dynamicColumns.shift();
    dynamicColumnDefFixture.detectChanges();
    expectTableToMatchContent(dynamicColumnDefTable, [
      [columnB], // Header row
      [columnB], // Data rows
      [columnB],
      [columnB],
    ]);
  });

  it('should re-render the rows when the data changes', () => {
    dataSource.addData();
    fixture.detectChanges();

    expect(getRows(tableElement).length).toBe(dataSource.data.length);

    // Check that the number of cells is correct
    getRows(tableElement).forEach(row => {
      expect(getCells(row).length).toBe(component.columnsToRender.length);
    });
  });

  it('should use differ to add/remove/move rows', () => {
    // Each row receives an attribute 'initialIndex' the element's original place
    getRows(tableElement).forEach((row: Element, index: number) => {
      row.setAttribute('initialIndex', index.toString());
    });

    // Prove that the attributes match their indicies
    const initialRows = getRows(tableElement);
    expect(initialRows[0].getAttribute('initialIndex')).toBe('0');
    expect(initialRows[1].getAttribute('initialIndex')).toBe('1');
    expect(initialRows[2].getAttribute('initialIndex')).toBe('2');

    // Swap first and second data in data array
    const copiedData = component.dataSource!.data.slice();
    const temp = copiedData[0];
    copiedData[0] = copiedData[1];
    copiedData[1] = temp;

    // Remove the third element
    copiedData.splice(2, 1);

    // Add new data
    component.dataSource!.data = copiedData;
    component.dataSource!.addData();

    // Expect that the first and second rows were swapped and that the last row is new
    const changedRows = getRows(tableElement);
    expect(changedRows.length).toBe(3);
    expect(changedRows[0].getAttribute('initialIndex')).toBe('1');
    expect(changedRows[1].getAttribute('initialIndex')).toBe('0');
    expect(changedRows[2].getAttribute('initialIndex')).toBe(null);
  });

  it('should clear the row view containers on destroy', () => {
    const rowPlaceholder = fixture.componentInstance.table._rowPlaceholder.viewContainer;
    const headerPlaceholder = fixture.componentInstance.table._headerRowPlaceholder.viewContainer;

    spyOn(rowPlaceholder, 'clear').and.callThrough();
    spyOn(headerPlaceholder, 'clear').and.callThrough();

    fixture.destroy();

    expect(rowPlaceholder.clear).toHaveBeenCalled();
    expect(headerPlaceholder.clear).toHaveBeenCalled();
  });

  describe('with trackBy', () => {

    let trackByComponent: TrackByCdkTableApp;
    let trackByFixture: ComponentFixture<TrackByCdkTableApp>;

    function createTestComponentWithTrackyByTable(trackByStrategy) {
      trackByFixture = TestBed.createComponent(TrackByCdkTableApp);

      trackByComponent = trackByFixture.componentInstance;
      trackByComponent.trackByStrategy = trackByStrategy;

      dataSource = trackByComponent.dataSource as FakeDataSource;
      table = trackByComponent.table;
      tableElement = trackByFixture.nativeElement.querySelector('cdk-table');
      trackByFixture.detectChanges();

      // Each row receives an attribute 'initialIndex' the element's original place
      getRows(tableElement).forEach((row: Element, index: number) => {
        row.setAttribute('initialIndex', index.toString());
      });

      // Prove that the attributes match their indicies
      const initialRows = getRows(tableElement);
      expect(initialRows[0].getAttribute('initialIndex')).toBe('0');
      expect(initialRows[1].getAttribute('initialIndex')).toBe('1');
      expect(initialRows[2].getAttribute('initialIndex')).toBe('2');
    }

    // Swap first two elements, remove the third, add new data
    function mutateData() {
      // Swap first and second data in data array
      const copiedData = trackByComponent.dataSource.data.slice();
      const temp = copiedData[0];
      copiedData[0] = copiedData[1];
      copiedData[1] = temp;

      // Remove the third element
      copiedData.splice(2, 1);

      // Add new data
      trackByComponent.dataSource.data = copiedData;
      trackByComponent.dataSource.addData();
    }

    it('should add/remove/move rows with reference-based trackBy', () => {
      createTestComponentWithTrackyByTable('reference');
      mutateData();

      // Expect that the first and second rows were swapped and that the last row is new
      const changedRows = getRows(tableElement);
      expect(changedRows.length).toBe(3);
      expect(changedRows[0].getAttribute('initialIndex')).toBe('1');
      expect(changedRows[1].getAttribute('initialIndex')).toBe('0');
      expect(changedRows[2].getAttribute('initialIndex')).toBe(null);
    });

    it('should add/remove/move rows with changed references without property-based trackBy', () => {
      createTestComponentWithTrackyByTable('reference');
      mutateData();

      // Change each item reference to show that the trackby is not checking the item properties.
      trackByComponent.dataSource.data = trackByComponent.dataSource.data
          .map(item => { return {a: item.a, b: item.b, c: item.c}; });

      // Expect that all the rows are considered new since their references are all different
      const changedRows = getRows(tableElement);
      expect(changedRows.length).toBe(3);
      expect(changedRows[0].getAttribute('initialIndex')).toBe(null);
      expect(changedRows[1].getAttribute('initialIndex')).toBe(null);
      expect(changedRows[2].getAttribute('initialIndex')).toBe(null);
    });

    it('should add/remove/move rows with changed references with property-based trackBy', () => {
      createTestComponentWithTrackyByTable('propertyA');
      mutateData();

      // Change each item reference to show that the trackby is checking the item properties.
      // Otherwise this would cause them all to be removed/added.
      trackByComponent.dataSource.data = trackByComponent.dataSource.data
          .map(item => { return {a: item.a, b: item.b, c: item.c}; });

      // Expect that the first and second rows were swapped and that the last row is new
      const changedRows = getRows(tableElement);
      expect(changedRows.length).toBe(3);
      expect(changedRows[0].getAttribute('initialIndex')).toBe('1');
      expect(changedRows[1].getAttribute('initialIndex')).toBe('0');
      expect(changedRows[2].getAttribute('initialIndex')).toBe(null);
    });

    it('should add/remove/move rows with changed references with index-based trackBy', () => {
      createTestComponentWithTrackyByTable('index');
      mutateData();

      // Change each item reference to show that the trackby is checking the index.
      // Otherwise this would cause them all to be removed/added.
      trackByComponent.dataSource.data = trackByComponent.dataSource.data
          .map(item => { return {a: item.a, b: item.b, c: item.c}; });

      // Expect first two to be the same since they were swapped but indicies are consistent.
      // The third element was removed and caught by the table so it was removed before another
      // item was added, so it is without an initial index.
      const changedRows = getRows(tableElement);
      expect(changedRows.length).toBe(3);
      expect(changedRows[0].getAttribute('initialIndex')).toBe('0');
      expect(changedRows[1].getAttribute('initialIndex')).toBe('1');
      expect(changedRows[2].getAttribute('initialIndex')).toBe(null);
    });
  });

  it('should match the right table content with dynamic data', () => {
    const initialDataLength = dataSource.data.length;
    expect(dataSource.data.length).toBe(3);

    let data = dataSource.data;
    expectTableToMatchContent(tableElement, [
      ['Column A', 'Column B', 'Column C'],
      [data[0].a, data[0].b, data[0].c],
      [data[1].a, data[1].b, data[1].c],
      [data[2].a, data[2].b, data[2].c],
    ]);

    // Add data to the table and recreate what the rendered output should be.
    dataSource.addData();
    expect(dataSource.data.length).toBe(initialDataLength + 1); // Make sure data was added
    fixture.detectChanges();

    data = dataSource.data;
    expectTableToMatchContent(tableElement, [
      ['Column A', 'Column B', 'Column C'],
      [data[0].a, data[0].b, data[0].c],
      [data[1].a, data[1].b, data[1].c],
      [data[2].a, data[2].b, data[2].c],
      [data[3].a, data[3].b, data[3].c],
    ]);
  });

  it('should match the right table content with dynamic data source', () => {
    const dynamicDataSourceFixture = TestBed.createComponent(DynamicDataSourceCdkTableApp);
    component = dynamicDataSourceFixture.componentInstance;
    tableElement = dynamicDataSourceFixture.nativeElement.querySelector('cdk-table');
    dynamicDataSourceFixture.detectChanges();

    // Expect that the component has no data source and the table element reflects empty data.
    expect(component.dataSource).toBe(undefined);
    expectTableToMatchContent(tableElement, [
      ['Column A']
    ]);

    // Add a data source that has initialized data. Expect that the table shows this data.
    const dynamicDataSource = new FakeDataSource();
    component.dataSource = dynamicDataSource;
    dynamicDataSourceFixture.detectChanges();
    expect(dynamicDataSource.isConnected).toBe(true);

    const data = component.dataSource.data;
    expectTableToMatchContent(tableElement, [
      ['Column A'],
      [data[0].a],
      [data[1].a],
      [data[2].a],
    ]);

    // Remove the data source and check to make sure the table is empty again.
    component.dataSource = null;
    dynamicDataSourceFixture.detectChanges();

    // Expect that the old data source has been disconnected.
    expect(dynamicDataSource.isConnected).toBe(false);
    expectTableToMatchContent(tableElement, [
      ['Column A']
    ]);

    // Reconnect a data source and check that the table is populated
    const newDynamicDataSource = new FakeDataSource();
    component.dataSource = newDynamicDataSource;
    dynamicDataSourceFixture.detectChanges();
    expect(newDynamicDataSource.isConnected).toBe(true);

    const newData = component.dataSource.data;
    expectTableToMatchContent(tableElement, [
      ['Column A'],
      [newData[0].a],
      [newData[1].a],
      [newData[2].a],
    ]);
  });

  it('should be able to apply classes to rows based on their context', () => {
    const contextFixture = TestBed.createComponent(RowContextCdkTableApp);
    const contextComponent = contextFixture.componentInstance;
    tableElement = contextFixture.nativeElement.querySelector('cdk-table');
    contextFixture.detectChanges();

    let rowElements = contextFixture.nativeElement.querySelectorAll('cdk-row');

    // Rows should not have any context classes
    for (let i = 0; i < rowElements.length; i++) {
      expect(rowElements[i].classList.contains('custom-row-class-first')).toBe(false);
      expect(rowElements[i].classList.contains('custom-row-class-last')).toBe(false);
      expect(rowElements[i].classList.contains('custom-row-class-even')).toBe(false);
      expect(rowElements[i].classList.contains('custom-row-class-odd')).toBe(false);
    }

    // Enable all the context classes
    contextComponent.enableRowContextClasses = true;
    contextFixture.detectChanges();

    expect(rowElements[0].classList.contains('custom-row-class-first')).toBe(true);
    expect(rowElements[0].classList.contains('custom-row-class-last')).toBe(false);
    expect(rowElements[0].classList.contains('custom-row-class-even')).toBe(true);
    expect(rowElements[0].classList.contains('custom-row-class-odd')).toBe(false);

    expect(rowElements[1].classList.contains('custom-row-class-first')).toBe(false);
    expect(rowElements[1].classList.contains('custom-row-class-last')).toBe(false);
    expect(rowElements[1].classList.contains('custom-row-class-even')).toBe(false);
    expect(rowElements[1].classList.contains('custom-row-class-odd')).toBe(true);

    expect(rowElements[2].classList.contains('custom-row-class-first')).toBe(false);
    expect(rowElements[2].classList.contains('custom-row-class-last')).toBe(true);
    expect(rowElements[2].classList.contains('custom-row-class-even')).toBe(true);
    expect(rowElements[2].classList.contains('custom-row-class-odd')).toBe(false);
  });

  it('should be able to apply classes to cells based on their row context', () => {
    const contextFixture = TestBed.createComponent(RowContextCdkTableApp);
    const contextComponent = contextFixture.componentInstance;
    tableElement = contextFixture.nativeElement.querySelector('cdk-table');
    contextFixture.detectChanges();

    const rowElements = contextFixture.nativeElement.querySelectorAll('cdk-row');

    for (let i = 0; i < rowElements.length; i++) {
      // Cells should not have any context classes
      const cellElements = rowElements[i].querySelectorAll('cdk-cell');
      for (let j = 0; j < cellElements.length; j++) {
        expect(cellElements[j].classList.contains('custom-cell-class-first')).toBe(false);
        expect(cellElements[j].classList.contains('custom-cell-class-last')).toBe(false);
        expect(cellElements[j].classList.contains('custom-cell-class-even')).toBe(false);
        expect(cellElements[j].classList.contains('custom-cell-class-odd')).toBe(false);
      }
    }

    // Enable the context classes
    contextComponent.enableCellContextClasses = true;
    contextFixture.detectChanges();

    let cellElement = rowElements[0].querySelectorAll('cdk-cell')[0];
    expect(cellElement.classList.contains('custom-cell-class-first')).toBe(true);
    expect(cellElement.classList.contains('custom-cell-class-last')).toBe(false);
    expect(cellElement.classList.contains('custom-cell-class-even')).toBe(true);
    expect(cellElement.classList.contains('custom-cell-class-odd')).toBe(false);

    cellElement = rowElements[1].querySelectorAll('cdk-cell')[0];
    expect(cellElement.classList.contains('custom-cell-class-first')).toBe(false);
    expect(cellElement.classList.contains('custom-cell-class-last')).toBe(false);
    expect(cellElement.classList.contains('custom-cell-class-even')).toBe(false);
    expect(cellElement.classList.contains('custom-cell-class-odd')).toBe(true);

    cellElement = rowElements[2].querySelectorAll('cdk-cell')[0];
    expect(cellElement.classList.contains('custom-cell-class-first')).toBe(false);
    expect(cellElement.classList.contains('custom-cell-class-last')).toBe(true);
    expect(cellElement.classList.contains('custom-cell-class-even')).toBe(true);
    expect(cellElement.classList.contains('custom-cell-class-odd')).toBe(false);
  });

  it('should be able to dynamically change the columns for header and rows', () => {
    expect(dataSource.data.length).toBe(3);

    let data = dataSource.data;
    expectTableToMatchContent(tableElement, [
      ['Column A', 'Column B', 'Column C'],
      [data[0].a, data[0].b, data[0].c],
      [data[1].a, data[1].b, data[1].c],
      [data[2].a, data[2].b, data[2].c],
    ]);

    // Remove column_a and swap column_b/column_c.
    component.columnsToRender = ['column_c', 'column_b'];
    fixture.detectChanges();

    let changedTableContent = [['Column C', 'Column B']];
    dataSource.data.forEach(rowData => changedTableContent.push([rowData.c, rowData.b]));

    data = dataSource.data;
    expectTableToMatchContent(tableElement, [
      ['Column C', 'Column B'],
      [data[0].c, data[0].b],
      [data[1].c, data[1].b],
      [data[2].c, data[2].b],
    ]);
  });
});

interface TestData {
  a: string;
  b: string;
  c: string;
}

class FakeDataSource extends DataSource<TestData> {
  isConnected = false;

  _dataChange = new BehaviorSubject<TestData[]>([]);
  set data(data: TestData[]) { this._dataChange.next(data); }
  get data() { return this._dataChange.getValue(); }

  constructor() {
    super();
    for (let i = 0; i < 3; i++) { this.addData(); }
  }

  connect(collectionViewer: CollectionViewer): Observable<TestData[]> {
    this.isConnected = true;
    const streams = [this._dataChange, collectionViewer.viewChange];
    return map.call(combineLatest(streams), ([data]) => data);
  }

  disconnect() {
    this.isConnected = false;
  }

  addData() {
    const nextIndex = this.data.length + 1;

    let copiedData = this.data.slice();
    copiedData.push({
      a: `a_${nextIndex}`,
      b: `b_${nextIndex}`,
      c: `c_${nextIndex}`
    });

    this.data = copiedData;
  }
}

@Component({
  template: `
    <cdk-table [dataSource]="dataSource">
      <ng-container cdkColumnDef="column_a">
        <cdk-header-cell *cdkHeaderCellDef> Column A</cdk-header-cell>
        <cdk-cell *cdkCellDef="let row"> {{row.a}}</cdk-cell>
      </ng-container>

      <ng-container cdkColumnDef="column_b">
        <cdk-header-cell *cdkHeaderCellDef> Column B</cdk-header-cell>
        <cdk-cell *cdkCellDef="let row"> {{row.b}}</cdk-cell>
      </ng-container>

      <ng-container cdkColumnDef="column_c">
        <cdk-header-cell *cdkHeaderCellDef> Column C</cdk-header-cell>
        <cdk-cell *cdkCellDef="let row"> {{row.c}}</cdk-cell>
      </ng-container>

      <cdk-header-row class="customHeaderRowClass"
                      *cdkHeaderRowDef="columnsToRender"></cdk-header-row>
      <cdk-row class="customRowClass"
               *cdkRowDef="let row; columns: columnsToRender"></cdk-row>
    </cdk-table>
  `
})
class SimpleCdkTableApp {
  dataSource: FakeDataSource | null = new FakeDataSource();
  columnsToRender = ['column_a', 'column_b', 'column_c'];

  @ViewChild(CdkTable) table: CdkTable<TestData>;
}

@Component({
  template: `
    <cdk-table [dataSource]="dataSource">
      <ng-container cdkColumnDef="column_a">
        <cdk-header-cell *cdkHeaderCellDef> Column A</cdk-header-cell>
        <cdk-cell *cdkCellDef="let row"> {{row.a}}</cdk-cell>
      </ng-container>

      <cdk-header-row *cdkHeaderRowDef="columnsToRender"></cdk-header-row>
      <cdk-row *cdkRowDef="let row; columns: columnsToRender"></cdk-row>
    </cdk-table>
  `
})
class DynamicDataSourceCdkTableApp {
  dataSource: FakeDataSource;
  columnsToRender = ['column_a'];

  @ViewChild(CdkTable) table: CdkTable<TestData>;
}

@Component({
  template: `
    <cdk-table [dataSource]="dataSource" [trackBy]="trackBy">
      <ng-container cdkColumnDef="column_a">
        <cdk-header-cell *cdkHeaderCellDef> Column A</cdk-header-cell>
        <cdk-cell *cdkCellDef="let row"> {{row.a}}</cdk-cell>
      </ng-container>

      <ng-container cdkColumnDef="column_b">
        <cdk-header-cell *cdkHeaderCellDef> Column B</cdk-header-cell>
        <cdk-cell *cdkCellDef="let row"> {{row.b}}</cdk-cell>
      </ng-container>

      <cdk-header-row *cdkHeaderRowDef="columnsToRender"></cdk-header-row>
      <cdk-row *cdkRowDef="let row; columns: columnsToRender"></cdk-row>
    </cdk-table>
  `
})
class TrackByCdkTableApp {
  trackByStrategy: 'reference' | 'propertyA' | 'index' = 'reference';

  dataSource: FakeDataSource = new FakeDataSource();
  columnsToRender = ['column_a', 'column_b'];

  @ViewChild(CdkTable) table: CdkTable<TestData>;

  trackBy = (index: number, item: TestData) => {
    switch (this.trackByStrategy) {
      case 'reference': return item;
      case 'propertyA': return item.a;
      case 'index': return index;
    }
  }
}

@Component({
  template: `
    <cdk-table [dataSource]="dataSource">
      <ng-container [cdkColumnDef]="column" *ngFor="let column of dynamicColumns">
        <cdk-header-cell *cdkHeaderCellDef> {{column}} </cdk-header-cell>
        <cdk-cell *cdkCellDef="let row"> {{column}} </cdk-cell>
      </ng-container>

      <cdk-header-row *cdkHeaderRowDef="dynamicColumns"></cdk-header-row>
      <cdk-row *cdkRowDef="let row; columns: dynamicColumns;"></cdk-row>
    </cdk-table>
  `
})
class DynamicColumnDefinitionsCdkTableApp {
  dynamicColumns: any[] = [];
  dataSource: FakeDataSource = new FakeDataSource();

  @ViewChild(CdkTable) table: CdkTable<TestData>;
}

@Component({
  template: `
    <cdk-table [dataSource]="dataSource" role="treegrid">
      <ng-container cdkColumnDef="column_a">
        <cdk-header-cell *cdkHeaderCellDef> Column A</cdk-header-cell>
        <cdk-cell *cdkCellDef="let row"> {{row.a}}</cdk-cell>
      </ng-container>

      <cdk-header-row *cdkHeaderRowDef="columnsToRender"></cdk-header-row>
      <cdk-row *cdkRowDef="let row; columns: columnsToRender"></cdk-row>
    </cdk-table>
  `
})
class CustomRoleCdkTableApp {
  dataSource: FakeDataSource = new FakeDataSource();
  columnsToRender = ['column_a'];

  @ViewChild(CdkTable) table: CdkTable<TestData>;
}

@Component({
  template: `
    <cdk-table [dataSource]="dataSource">
      <ng-container cdkColumnDef="column_a">
        <cdk-header-cell *cdkHeaderCellDef> Column A</cdk-header-cell>
        <cdk-cell *cdkCellDef="let row"> {{row.a}}</cdk-cell>
      </ng-container>

      <ng-container cdkColumnDef="column_a">
        <cdk-header-cell *cdkHeaderCellDef> Column A</cdk-header-cell>
        <cdk-cell *cdkCellDef="let row"> {{row.a}}</cdk-cell>
      </ng-container>

      <cdk-header-row *cdkHeaderRowDef="['column_a']"></cdk-header-row>
      <cdk-row *cdkRowDef="let row; columns: ['column_a']"></cdk-row>
    </cdk-table>
  `
})
class DuplicateColumnDefNameCdkTableApp {
  dataSource: FakeDataSource = new FakeDataSource();
}

@Component({
  template: `
    <cdk-table [dataSource]="dataSource">
      <ng-container cdkColumnDef="column_b">
        <cdk-header-cell *cdkHeaderCellDef> Column A</cdk-header-cell>
        <cdk-cell *cdkCellDef="let row"> {{row.a}}</cdk-cell>
      </ng-container>

      <cdk-header-row *cdkHeaderRowDef="['column_a']"></cdk-header-row>
      <cdk-row *cdkRowDef="let row; columns: ['column_a']"></cdk-row>
    </cdk-table>
  `
})
class MissingColumnDefCdkTableApp {
  dataSource: FakeDataSource = new FakeDataSource();
}

@Component({
  template: `
    <cdk-table [dataSource]="dataSource">
      <ng-container cdkColumnDef="column_a">
        <cdk-header-cell *cdkHeaderCellDef> Column A</cdk-header-cell>
        <cdk-cell *cdkCellDef="let row; let first = first;
                               let last = last; let even = even; let odd = odd"
                  [ngClass]="{
                    'custom-cell-class-first': enableCellContextClasses && first,
                    'custom-cell-class-last': enableCellContextClasses && last,
                    'custom-cell-class-even': enableCellContextClasses && even,
                    'custom-cell-class-odd': enableCellContextClasses && odd
                  }">
          {{row.a}}
        </cdk-cell>
      </ng-container>
      <cdk-header-row *cdkHeaderRowDef="columnsToRender"></cdk-header-row>
      <cdk-row *cdkRowDef="let row; columns: columnsToRender;
                           let first = first; let last = last; let even = even; let odd = odd"
               [ngClass]="{
                 'custom-row-class-first': enableRowContextClasses && first,
                 'custom-row-class-last': enableRowContextClasses && last,
                 'custom-row-class-even': enableRowContextClasses && even,
                 'custom-row-class-odd': enableRowContextClasses && odd
               }">
      </cdk-row>
    </cdk-table>
  `
})
class RowContextCdkTableApp {
  dataSource: FakeDataSource = new FakeDataSource();
  columnsToRender = ['column_a'];
  enableRowContextClasses = false;
  enableCellContextClasses = false;
}

function getElements(element: Element, query: string): Element[] {
  return [].slice.call(element.querySelectorAll(query));
}

function getHeaderRow(tableElement: Element): Element {
  return tableElement.querySelector('.cdk-header-row')!;
}

function getRows(tableElement: Element): Element[] {
  return getElements(tableElement, '.cdk-row');
}
function getCells(row: Element): Element[] {
  return row ? getElements(row, '.cdk-cell') : [];
}

function getHeaderCells(tableElement: Element): Element[] {
  return getElements(getHeaderRow(tableElement), '.cdk-header-cell');
}

function expectTableToMatchContent(tableElement: Element, expectedTableContent: any[]) {
  const missedExpectations: string[] = [];
  function checkCellContent(cell: Element, expectedTextContent: string) {
    const actualTextContent = cell.textContent!.trim();
    if (actualTextContent !== expectedTextContent) {
      missedExpectations.push(
          `Expected cell contents to be ${expectedTextContent} but was ${actualTextContent}`);
    }
  }

  // Check header cells
  const expectedHeaderContent = expectedTableContent.shift();
  getHeaderCells(tableElement).forEach((cell, index) => {
    const expected = expectedHeaderContent ?
        expectedHeaderContent[index] :
        null;
    checkCellContent(cell, expected);
  });

  // Check data row cells
  getRows(tableElement).forEach((row, rowIndex) => {
    getCells(row).forEach((cell, cellIndex) => {
      const expected = expectedTableContent.length ?
          expectedTableContent[rowIndex][cellIndex] :
          null;
      checkCellContent(cell, expected);
    });
  });

  if (missedExpectations.length) {
    fail(missedExpectations.join('\n'));
  }
}