output: buffered content tests

src/vs/workbench/parts/output/browser/outputServices.ts

@@ -29,7 +29,7 @@ import { Position } from 'vs/editor/common/core/position';
 
 const OUTPUT_ACTIVE_CHANNEL_KEY = 'output.activechannel';
 
-class BufferedContent {
+export class BufferedContent {
 
 	private data: string[] = [];
 	private dataIds: number[] = [];
@@ -61,14 +61,14 @@ class BufferedContent {
 		}
 	}
 
-	public value(previousDelta?: IOutputDelta): IOutputDelta {
+	public getDelta(previousDelta?: IOutputDelta): IOutputDelta {
 		let idx = -1;
 		if (previousDelta) {
 			idx = binarySearch(this.dataIds, previousDelta.id, (a, b) => a - b);
 		}
 
 		const id = this.idPool;
-		if (idx >= 0) {
+		if (idx > 0) {
 			const value = strings.removeAnsiEscapeCodes(this.data.slice(idx).join(''));
 			return { value, id, append: true };
 		} else {
@@ -183,9 +183,9 @@ export class OutputService implements IOutputService {
 		return this.getChannel(this.activeChannelId);
 	}
 
-	private getOutput(channelId: string, before: IOutputDelta): IOutputDelta {
+	private getOutput(channelId: string, previousDelta: IOutputDelta): IOutputDelta {
 		if (this.receivedOutput.has(channelId)) {
-			return this.receivedOutput.get(channelId).value(before);
+			return this.receivedOutput.get(channelId).getDelta(previousDelta);
 		}
 
 		return undefined;

src/vs/workbench/parts/output/test/bufferedContent.test.ts

+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import * as assert from 'assert';
+import { BufferedContent } from 'vs/workbench/parts/output/browser/outputServices';
+
+suite('Workbench - Output Buffered Content', () => {
+
+	test('Buffered Content - Simple', () => {
+		const bufferedContent = new BufferedContent();
+		bufferedContent.append('first');
+		bufferedContent.append('second');
+		bufferedContent.append('third');
+		const delta = bufferedContent.getDelta();
+		assert.equal(bufferedContent.getDelta().value, 'firstsecondthird');
+		bufferedContent.clear();
+		assert.equal(bufferedContent.getDelta().value, '');
+		assert.equal(bufferedContent.getDelta(delta).value, '');
+	});
+
+	test('Buffered Content - Lots of output', () => {
+		const bufferedContent = new BufferedContent();
+		bufferedContent.append('first line');
+		const firstDelta = bufferedContent.getDelta();
+		for (var i = 0; i < 100000; i++) {
+			bufferedContent.append(i.toString());
+		}
+		const secondDelta = bufferedContent.getDelta(firstDelta);
+		assert.equal(!!secondDelta.append, false);
+		assert.equal(secondDelta.value.substr(secondDelta.value.length - 5), '99999');
+		bufferedContent.clear();
+		assert.equal(bufferedContent.getDelta().value, '');
+	});
+});