Fixes #18353: Always respect the `shouldIgnoreTrimWhitespace` flag

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

@@ -34,24 +34,6 @@ class MarkerSequence implements ISequence {
 		this.endMarkers = endMarkers;
 	}
 
-	public equals(other: any): boolean {
-		if (!(other instanceof MarkerSequence)) {
-			return false;
-		}
-		const otherMarkerSequence = <MarkerSequence>other;
-		if (this.getLength() !== otherMarkerSequence.getLength()) {
-			return false;
-		}
-		for (let i = 0, len = this.getLength(); i < len; i++) {
-			const myElement = this.getElementHash(i);
-			const otherElement = otherMarkerSequence.getElementHash(i);
-			if (myElement !== otherElement) {
-				return false;
-			}
-		}
-		return true;
-	}
-
 	public getLength(): number {
 		return this.startMarkers.length;
 	}
@@ -321,7 +303,6 @@ class LineChange implements ILineChange {
 export interface IDiffComputerOpts {
 	shouldPostProcessCharChanges: boolean;
 	shouldIgnoreTrimWhitespace: boolean;
-	shouldConsiderTrimWhitespaceInEmptyCase: boolean;
 	shouldMakePrettyDiff: boolean;
 }
 
@@ -347,11 +328,6 @@ export class DiffComputer {
 		this.modifiedLines = modifiedLines;
 		this.original = new LineMarkerSequence(originalLines);
 		this.modified = new LineMarkerSequence(modifiedLines);
-
-		if (opts.shouldConsiderTrimWhitespaceInEmptyCase && this.shouldIgnoreTrimWhitespace && this.original.equals(this.modified)) {
-			// Diff would be empty with `shouldIgnoreTrimWhitespace`
-			this.shouldIgnoreTrimWhitespace = false;
-		}
 	}
 
 	public computeDiff(): ILineChange[] {

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

@@ -313,7 +313,6 @@ export abstract class BaseEditorSimpleWorker {
 		let diffComputer = new DiffComputer(originalLines, modifiedLines, {
 			shouldPostProcessCharChanges: true,
 			shouldIgnoreTrimWhitespace: ignoreTrimWhitespace,
-			shouldConsiderTrimWhitespaceInEmptyCase: true,
 			shouldMakePrettyDiff: true
 		});
 		return TPromise.as(diffComputer.computeDiff());
@@ -331,7 +330,6 @@ export abstract class BaseEditorSimpleWorker {
 		let diffComputer = new DiffComputer(originalLines, modifiedLines, {
 			shouldPostProcessCharChanges: false,
 			shouldIgnoreTrimWhitespace: ignoreTrimWhitespace,
-			shouldConsiderTrimWhitespaceInEmptyCase: false,
 			shouldMakePrettyDiff: true
 		});
 		return TPromise.as(diffComputer.computeDiff());

src/vs/editor/test/common/diff/diffComputer.test.ts

@@ -55,7 +55,6 @@ function assertDiff(originalLines: string[], modifiedLines: string[], expectedCh
 	var diffComputer = new DiffComputer(originalLines, modifiedLines, {
 		shouldPostProcessCharChanges: shouldPostProcessCharChanges || false,
 		shouldIgnoreTrimWhitespace: shouldIgnoreTrimWhitespace || false,
-		shouldConsiderTrimWhitespaceInEmptyCase: true,
 		shouldMakePrettyDiff: true
 	});
 	var changes = diffComputer.computeDiff();