put drag and drop behind an option and turn it off by default

src/vs/editor/browser/controller/mouseHandler.ts

@@ -429,7 +429,8 @@ class MouseDownOperation extends Disposable {
 		// Overwrite the detail of the MouseEvent, as it will be sent out in an event and contributions might rely on it.
 		e.detail = this._mouseState.count;
 
-		if (!this._mouseState.altKey // we don't support multiple mouse
+		if (this._context.configuration.editor.enableDragAndDrop
+			&& !this._mouseState.altKey // we don't support multiple mouse
 			&& e.detail < 2 // only single click on a selection can work
 			&& !this._isActive // the mouse is not down yet
 			&& !this._currentSelection.isEmpty() // we don't drag single cursor

src/vs/editor/common/config/commonEditorConfig.ts

@@ -317,6 +317,7 @@ class InternalEditorOptionsHelper {
 			autoClosingBrackets: toBoolean(opts.autoClosingBrackets),
 			useTabStops: toBoolean(opts.useTabStops),
 			tabFocusMode: tabFocusMode,
+			enableDragAndDrop: toBoolean(opts.enableDragAndDrop),
 			layoutInfo: layoutInfo,
 			fontInfo: fontInfo,
 			viewInfo: viewInfo,
@@ -842,6 +843,11 @@ const editorConfiguration: IConfigurationNode = {
 			'default': false,
 			'description': nls.localize('stablePeek', "Keep peek editors open even when double clicking their content or when hitting Escape.")
 		},
+		'editor.enableDragAndDrop': {
+			'type': 'boolean',
+			'default': DefaultConfig.editor.enableDragAndDrop,
+			'description': nls.localize('enableDragAndDrop', "Controls if the editor should allow to move selections via drag and drop.")
+		},
 		'diffEditor.renderSideBySide': {
 			'type': 'boolean',
 			'default': true,

src/vs/editor/common/config/defaultConfig.ts

@@ -106,6 +106,7 @@ class ConfigClass implements IConfiguration {
 			renderLineHighlight: 'line',
 			useTabStops: true,
 			matchBrackets: true,
+			enableDragAndDrop: false,
 
 			fontFamily: (
 				platform.isMacintosh ? DEFAULT_MAC_FONT_FAMILY : (platform.isLinux ? DEFAULT_LINUX_FONT_FAMILY : DEFAULT_WINDOWS_FONT_FAMILY)

src/vs/editor/common/editorCommon.ts

@@ -419,6 +419,11 @@ export interface IEditorOptions {
 	 * Defaults to false.
 	 */
 	formatOnPaste?: boolean;
+	/**
+	 * Controls if the editor should allow to move selections via drag and drop.
+	 * Defaults to false.
+	 */
+	enableDragAndDrop?: boolean;
 	/**
 	 * Enable the suggestion box to pop-up on trigger characters.
 	 * Defaults to true.
@@ -1068,6 +1073,7 @@ export class InternalEditorOptions {
 	readonly autoClosingBrackets: boolean;
 	readonly useTabStops: boolean;
 	readonly tabFocusMode: boolean;
+	readonly enableDragAndDrop: boolean;
 	// ---- grouped options
 	readonly layoutInfo: EditorLayoutInfo;
 	readonly fontInfo: FontInfo;
@@ -1085,6 +1091,7 @@ export class InternalEditorOptions {
 		autoClosingBrackets: boolean;
 		useTabStops: boolean;
 		tabFocusMode: boolean;
+		enableDragAndDrop: boolean;
 		layoutInfo: EditorLayoutInfo;
 		fontInfo: FontInfo;
 		viewInfo: InternalEditorViewOptions;
@@ -1097,6 +1104,7 @@ export class InternalEditorOptions {
 		this.autoClosingBrackets = Boolean(source.autoClosingBrackets);
 		this.useTabStops = Boolean(source.useTabStops);
 		this.tabFocusMode = Boolean(source.tabFocusMode);
+		this.enableDragAndDrop = Boolean(source.enableDragAndDrop);
 		this.layoutInfo = source.layoutInfo.clone();
 		this.fontInfo = source.fontInfo.clone();
 		this.viewInfo = source.viewInfo.clone();
@@ -1115,6 +1123,7 @@ export class InternalEditorOptions {
 			&& this.autoClosingBrackets === other.autoClosingBrackets
 			&& this.useTabStops === other.useTabStops
 			&& this.tabFocusMode === other.tabFocusMode
+			&& this.enableDragAndDrop === other.enableDragAndDrop
 			&& this.layoutInfo.equals(other.layoutInfo)
 			&& this.fontInfo.equals(other.fontInfo)
 			&& this.viewInfo.equals(other.viewInfo)
@@ -1134,6 +1143,7 @@ export class InternalEditorOptions {
 			autoClosingBrackets: (this.autoClosingBrackets !== newOpts.autoClosingBrackets),
 			useTabStops: (this.useTabStops !== newOpts.useTabStops),
 			tabFocusMode: (this.tabFocusMode !== newOpts.tabFocusMode),
+			enableDragAndDrop: (this.enableDragAndDrop !== newOpts.enableDragAndDrop),
 			layoutInfo: (!this.layoutInfo.equals(newOpts.layoutInfo)),
 			fontInfo: (!this.fontInfo.equals(newOpts.fontInfo)),
 			viewInfo: this.viewInfo.createChangeEvent(newOpts.viewInfo),
@@ -1160,6 +1170,7 @@ export interface IConfigurationChangedEvent {
 	readonly autoClosingBrackets: boolean;
 	readonly useTabStops: boolean;
 	readonly tabFocusMode: boolean;
+	readonly enableDragAndDrop: boolean;
 	readonly layoutInfo: boolean;
 	readonly fontInfo: boolean;
 	readonly viewInfo: IViewConfigurationChangedEvent;

src/vs/monaco.d.ts

@@ -1340,6 +1340,11 @@ declare module monaco.editor {
          * Defaults to false.
          */
         formatOnPaste?: boolean;
+        /**
+         * Controls if the editor should allow to move selections via drag and drop.
+         * Defaults to false.
+         */
+        enableDragAndDrop?: boolean;
         /**
          * Enable the suggestion box to pop-up on trigger characters.
          * Defaults to true.
@@ -1599,6 +1604,7 @@ declare module monaco.editor {
         readonly autoClosingBrackets: boolean;
         readonly useTabStops: boolean;
         readonly tabFocusMode: boolean;
+        readonly enableDragAndDrop: boolean;
         readonly layoutInfo: EditorLayoutInfo;
         readonly fontInfo: FontInfo;
         readonly viewInfo: InternalEditorViewOptions;
@@ -1616,6 +1622,7 @@ declare module monaco.editor {
         readonly autoClosingBrackets: boolean;
         readonly useTabStops: boolean;
         readonly tabFocusMode: boolean;
+        readonly enableDragAndDrop: boolean;
         readonly layoutInfo: boolean;
         readonly fontInfo: boolean;
         readonly viewInfo: IViewConfigurationChangedEvent;

src/vs/platform/telemetry/common/telemetryUtils.ts

@@ -213,6 +213,7 @@ const configurationValueWhitelist = [
 	'editor.formatOnType',
 	'editor.formatOnSave',
 	'editor.formatOnPaste',
+	'editor.enableDragAndDrop',
 	'window.openFilesInNewWindow',
 	'javascript.validate.enable',
 	'editor.mouseWheelZoom',