adds getters for diff algorithms (microsoft#185497)

Author: hediet

src/vs/editor/common/diff/linesDiffComputers.ts

@@ -7,6 +7,6 @@ import { SmartLinesDiffComputer } from 'vs/editor/common/diff/smartLinesDiffComp
 import { StandardLinesDiffComputer } from 'vs/editor/common/diff/standardLinesDiffComputer';
 
 export const linesDiffComputers = {
-	legacy: new SmartLinesDiffComputer(),
-	advanced: new StandardLinesDiffComputer(),
+	getLegacy: () => new SmartLinesDiffComputer(),
+	getAdvanced: () => new StandardLinesDiffComputer(),
 };

src/vs/editor/common/services/editorSimpleWorker.ts

@@ -413,7 +413,7 @@ export class EditorSimpleWorker implements IRequestHandler, IDisposable {
 	}
 
 	private static computeDiff(originalTextModel: ICommonModel | ITextModel, modifiedTextModel: ICommonModel | ITextModel, options: IDocumentDiffProviderOptions, algorithm: DiffAlgorithmName): IDiffComputationResult {
-		const diffAlgorithm: ILinesDiffComputer = algorithm === 'advanced' ? linesDiffComputers.advanced : linesDiffComputers.legacy;
+		const diffAlgorithm: ILinesDiffComputer = algorithm === 'advanced' ? linesDiffComputers.getAdvanced() : linesDiffComputers.getLegacy();
 
 		const originalLines = originalTextModel.getLinesContent();
 		const modifiedLines = modifiedTextModel.getLinesContent();
@@ -609,7 +609,7 @@ export class EditorSimpleWorker implements IRequestHandler, IDisposable {
 			const originalLines = original.split(/\r\n|\n|\r/);
 			const modifiedLines = text.split(/\r\n|\n|\r/);
 
-			const diff = linesDiffComputers.advanced.computeDiff(originalLines, modifiedLines, options);
+			const diff = linesDiffComputers.getAdvanced().computeDiff(originalLines, modifiedLines, options);
 
 			const start = Range.lift(range).getStartPosition();
 

src/vs/workbench/contrib/mergeEditor/test/browser/model.test.ts

@@ -283,7 +283,7 @@ class MergeModelInterface extends Disposable {
 
 		const diffComputer: IMergeDiffComputer = {
 			async computeDiff(textModel1: ITextModel, textModel2: ITextModel, reader: IReader): Promise<IMergeDiffComputerResult> {
-				const result = await linesDiffComputers.legacy.computeDiff(
+				const result = await linesDiffComputers.getLegacy().computeDiff(
 					textModel1.getLinesContent(),
 					textModel2.getLinesContent(),
 					{ ignoreTrimWhitespace: false, maxComputationTimeMs: 10000, computeMoves: false }