add tests for errors

Author: andrewseguin

src/cdk/table/table-errors.ts

@@ -0,0 +1,16 @@
+/**
+ * Returns an error to be thrown when attempting to find an unexisting column.
+ * @param id Id whose lookup failed.
+ * @docs-private
+ */
+export function getTableUnknownColumnError(id: string) {
+  return Error(`cdk-table: Could not find column with id "${id}".`);
+}
+
+/**
+ * Returns an error to be thrown when two column definitions have the same name.
+ * @docs-private
+ */
+export function getTableDuplicateColumnNameError(name: string) {
+  return Error(`cdk-table: Duplicate column definition name provided: "${name}".`);
+}

src/cdk/table/table.spec.ts

@@ -7,6 +7,7 @@ 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>;
@@ -26,6 +27,8 @@ describe('CdkTable', () => {
         TrackByCdkTableApp,
         DynamicColumnDefinitionsCdkTableApp,
         RowContextCdkTableApp,
+        DuplicateColumnDefNameCdkTableApp,
+        MissingColumnDefCdkTableApp,
       ],
     }).compileComponents();
   }));
@@ -109,6 +112,16 @@ describe('CdkTable', () => {
     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();
@@ -666,6 +679,45 @@ class CustomRoleCdkTableApp {
   @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">

src/cdk/table/table.ts

@@ -36,23 +36,7 @@ import {BehaviorSubject} from 'rxjs/BehaviorSubject';
 import {Subscription} from 'rxjs/Subscription';
 import {Subject} from 'rxjs/Subject';
 import {CdkCellDef, CdkColumnDef, CdkHeaderCellDef} from './cell';
-
-/**
- * Returns an error to be thrown when attempting to find an unexisting column.
- * @param id Id whose lookup failed.
- * @docs-private
- */
-export function getTableUnknownColumnError(id: string) {
-  return new Error(`cdk-table: Could not find column with id "${id}".`);
-}
-
-/**
- * Returns an error to be thrown when attempting to find an unexisting column.
- * @docs-private
- */
-export function getTableDuplicateColumnNameError(name: string) {
-  return new Error(`cdk-table: Duplicate column definition name provided: "${name}".`);
-}
+import {getTableDuplicateColumnNameError, getTableUnknownColumnError} from './table-errors';
 
 /**
  * Provides a handle for the table to grab the view container's ng-container to insert data rows.