Fixes #9012: Add toggle for "ignore trim whitespace" while diffing

src/vs/workbench/browser/parts/editor/media/IgnoreTrimWhiteSpaceChecked_16x.svg

+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 16 16"><style>.st0{opacity:0}.st0,.st1{fill:#f6f6f6}.st2{fill:#424242}</style><g id="outline"><path class="st0" d="M0 0h16v16H0z"/><path class="st1" d="M12 4v8H4V4h8z"/></g><path class="st2" d="M5 9h6v2H5V9zm0-4v2h6V5H5z" id="icon_x5F_bg"/><rect fill="#000000" x="1" y="1" width="14" height="14" fill-opacity="0" stroke="#424242"></rect></svg>

src/vs/workbench/browser/parts/editor/media/IgnoreTrimWhiteSpaceChecked_16x_inverse.svg

+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 16 16"><style>.st0{opacity:0}.st0,.st1{fill:#252526}.st2{fill:#c5c5c5}</style><g id="outline"><path class="st0" d="M0 0h16v16H0z"/><path class="st1" d="M12 4v8H4V4h8z"/></g><path class="st2" d="M5 9h6v2H5V9zm0-4v2h6V5H5z" id="icon_x5F_bg"/><rect fill="#000000" x="1" y="1" width="14" height="14" fill-opacity="0" stroke="#c5c5c5"></rect></svg>

src/vs/workbench/browser/parts/editor/media/IgnoreTrimWhiteSpace_16x.svg

+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 16 16"><style>.st0{opacity:0}.st0,.st1{fill:#f6f6f6}.st2{fill:#424242}</style><g id="outline"><path class="st0" d="M0 0h16v16H0z"/><path class="st1" d="M12 4v8H4V4h8z"/></g><path class="st2" d="M5 9h6v2H5V9zm0-4v2h6V5H5z" id="icon_x5F_bg"/></svg>
\ No newline at end of file

src/vs/workbench/browser/parts/editor/media/IgnoreTrimWhiteSpace_16x_inverse.svg

+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 16 16"><style>.st0{opacity:0}.st0,.st1{fill:#252526}.st2{fill:#c5c5c5}</style><g id="outline"><path class="st0" d="M0 0h16v16H0z"/><path class="st1" d="M12 4v8H4V4h8z"/></g><path class="st2" d="M5 9h6v2H5V9zm0-4v2h6V5H5z" id="icon_x5F_bg"/></svg>
\ No newline at end of file

src/vs/workbench/browser/parts/editor/media/textdiffeditor.css

@@ -19,4 +19,20 @@
 .vs-dark .monaco-workbench .textdiff-editor-action.previous,
 .hc-black .monaco-workbench .textdiff-editor-action.previous {
 	background: url('previous-diff-inverse.svg') center center no-repeat;
-}
\ No newline at end of file
+}
+
+.vs .monaco-workbench .textdiff-editor-action.toggleIgnoreTrimWhitespace {
+	background: url('IgnoreTrimWhiteSpace_16x.svg') center center no-repeat;
+}
+.vs-dark .monaco-workbench .textdiff-editor-action.toggleIgnoreTrimWhitespace,
+.hc-black .monaco-workbench .textdiff-editor-action.toggleIgnoreTrimWhitespace {
+	background: url('IgnoreTrimWhiteSpace_16x_inverse.svg	') center center no-repeat;
+}
+
+.vs .monaco-workbench .textdiff-editor-action.toggleIgnoreTrimWhitespace.is-checked {
+	background: url('IgnoreTrimWhiteSpaceChecked_16x.svg') center center no-repeat;
+}
+.vs-dark .monaco-workbench .textdiff-editor-action.toggleIgnoreTrimWhitespace.is-checked,
+.hc-black .monaco-workbench .textdiff-editor-action.toggleIgnoreTrimWhitespace.is-checked {
+	background: url('IgnoreTrimWhiteSpaceChecked_16x_inverse.svg	') center center no-repeat;
+}

src/vs/workbench/browser/parts/editor/textDiffEditor.ts

@@ -34,6 +34,8 @@ import { IEditorGroupService } from 'vs/workbench/services/group/common/groupSer
 import { ITextFileService } from 'vs/workbench/services/textfile/common/textfiles';
 import { IEditorInput } from 'vs/platform/editor/common/editor';
 import { ScrollType } from 'vs/editor/common/editorCommon';
+import { IConfigurationService } from 'vs/platform/configuration/common/configuration';
+import { IDisposable } from 'vs/base/common/lifecycle';
 
 /**
  * The text editor that leverages the diff text editor for the editing experience.
@@ -45,18 +47,27 @@ export class TextDiffEditor extends BaseTextEditor {
 	private diffNavigator: DiffNavigator;
 	private nextDiffAction: NavigateAction;
 	private previousDiffAction: NavigateAction;
+	private toggleIgnoreTrimWhitespaceAction: ToggleIgnoreTrimWhitespaceAction;
+	private _configurationListener: IDisposable;
 
 	constructor(
 		@ITelemetryService telemetryService: ITelemetryService,
 		@IInstantiationService instantiationService: IInstantiationService,
 		@IStorageService storageService: IStorageService,
 		@ITextResourceConfigurationService configurationService: ITextResourceConfigurationService,
+		@IConfigurationService private readonly _actualConfigurationService: IConfigurationService,
 		@IWorkbenchEditorService private editorService: IWorkbenchEditorService,
 		@IThemeService themeService: IThemeService,
 		@IEditorGroupService editorGroupService: IEditorGroupService,
 		@ITextFileService textFileService: ITextFileService
 	) {
 		super(TextDiffEditor.ID, telemetryService, instantiationService, storageService, configurationService, themeService, textFileService, editorGroupService);
+
+		this._configurationListener = this._actualConfigurationService.onDidChangeConfiguration((e) => {
+			if (e.affectsConfiguration('diffEditor.ignoreTrimWhitespace')) {
+				this.updateIgnoreTrimWhitespaceAction();
+			}
+		});
 	}
 
 	public getTitle(): string {
@@ -72,6 +83,8 @@ export class TextDiffEditor extends BaseTextEditor {
 		// Actions
 		this.nextDiffAction = new NavigateAction(this, true);
 		this.previousDiffAction = new NavigateAction(this, false);
+		this.toggleIgnoreTrimWhitespaceAction = new ToggleIgnoreTrimWhitespaceAction(this._actualConfigurationService);
+		this.updateIgnoreTrimWhitespaceAction();
 
 		// Support navigation within the diff editor by overriding the editor service within
 		const delegatingEditorService = this.instantiationService.createInstance(DelegatingWorkbenchEditorService);
@@ -163,6 +176,7 @@ export class TextDiffEditor extends BaseTextEditor {
 					this.nextDiffAction.updateEnablement();
 					this.previousDiffAction.updateEnablement();
 				});
+				this.updateIgnoreTrimWhitespaceAction();
 			}, error => {
 
 				// In case we tried to open a file and the response indicates that this is not a text file, fallback to binary diff.
@@ -176,6 +190,13 @@ export class TextDiffEditor extends BaseTextEditor {
 		});
 	}
 
+	private updateIgnoreTrimWhitespaceAction(): void {
+		const ignoreTrimWhitespace = this.configurationService.getValue<boolean>(this.getResource(), 'diffEditor.ignoreTrimWhitespace');
+		if (this.toggleIgnoreTrimWhitespaceAction) {
+			this.toggleIgnoreTrimWhitespaceAction.updateClassName(ignoreTrimWhitespace);
+		}
+	}
+
 	private openAsBinary(input: EditorInput, options: EditorOptions): boolean {
 		if (input instanceof DiffEditorInput) {
 			const originalInput = input.originalInput;
@@ -273,6 +294,7 @@ export class TextDiffEditor extends BaseTextEditor {
 
 	public getActions(): IAction[] {
 		return [
+			this.toggleIgnoreTrimWhitespaceAction,
 			this.previousDiffAction,
 			this.nextDiffAction
 		];
@@ -303,6 +325,8 @@ export class TextDiffEditor extends BaseTextEditor {
 			this.diffNavigator.dispose();
 		}
 
+		this._configurationListener.dispose();
+
 		super.dispose();
 	}
 }
@@ -340,6 +364,29 @@ class NavigateAction extends Action {
 	}
 }
 
+class ToggleIgnoreTrimWhitespaceAction extends Action {
+	static ID = 'workbench.action.compareEditor.toggleIgnoreTrimWhitespace';
+
+	private _isChecked: boolean;
+
+	constructor(
+		@IConfigurationService private readonly _configurationService: IConfigurationService
+	) {
+		super(ToggleIgnoreTrimWhitespaceAction.ID);
+		this.label = nls.localize('toggleIgnoreTrimWhitespace.label', "Ignore Trim Whitespace");
+	}
+
+	public updateClassName(ignoreTrimWhitespace: boolean): void {
+		this._isChecked = ignoreTrimWhitespace;
+		this.class = `textdiff-editor-action toggleIgnoreTrimWhitespace${this._isChecked ? ' is-checked' : ''}`;
+	}
+
+	public run(): TPromise<any> {
+		this._configurationService.updateValue(`diffEditor.ignoreTrimWhitespace`, !this._isChecked);
+		return null;
+	}
+}
+
 class ToggleEditorModeAction extends Action {
 	private static readonly ID = 'toggle.diff.editorMode';
 	private static readonly INLINE_LABEL = nls.localize('inlineDiffLabel', "Switch to Inline View");