:sparkles: registerDiffInformationCommand instead of computeDiff

9 files changed, 89 insertions, 52 deletions

diff --git a/extensions/git/src/commands.ts b/extensions/git/src/commands.ts
index 3cdf9461078..6997c3a80e2 100644
--- a/extensions/git/src/commands.ts
+++ b/extensions/git/src/commands.ts
@@ -5,7 +5,7 @@
 
 'use strict';
 
-import { Uri, commands, scm, Disposable, window, workspace, QuickPickItem, OutputChannel, computeDiff, Range, WorkspaceEdit, Position } from 'vscode';
+import { Uri, commands, scm, Disposable, window, workspace, QuickPickItem, OutputChannel, Range, WorkspaceEdit, Position, LineChange } from 'vscode';
 import { Ref, RefType, Git } from './git';
 import { Model, Resource, Status, CommitOptions } from './model';
 import * as staging from './staging';
@@ -60,15 +60,23 @@ class CheckoutRemoteHeadItem extends CheckoutItem {
 	}
 }
 
-const Commands: { commandId: string; key: string; method: Function; skipModelCheck: boolean; }[] = [];
+interface Command {
+	commandId: string;
+	key: string;
+	method: Function;
+	skipModelCheck: boolean;
+	requiresDiffInformation: boolean;
+}
+
+const Commands: Command[] = [];
 
-function command(commandId: string, skipModelCheck = false): Function {
+function command(commandId: string, skipModelCheck = false, requiresDiffInformation = false): Function {
 	return (target: any, key: string, descriptor: any) => {
 		if (!(typeof descriptor.value === 'function')) {
 			throw new Error('not supported');
 		}
 
-		Commands.push({ commandId, key, method: descriptor.value, skipModelCheck });
+		Commands.push({ commandId, key, method: descriptor.value, skipModelCheck, requiresDiffInformation });
 	};
 }
 
@@ -88,7 +96,15 @@ export class CommandCenter {
 		}
 
 		this.disposables = Commands
-			.map(({ commandId, key, method, skipModelCheck }) => commands.registerCommand(commandId, this.createCommand(commandId, key, method, skipModelCheck)));
+			.map(({ commandId, key, method, skipModelCheck, requiresDiffInformation }) => {
+				const command = this.createCommand(commandId, key, method, skipModelCheck);
+
+				if (requiresDiffInformation) {
+					return commands.registerDiffInformationCommand(commandId, command);
+				} else {
+					return commands.registerCommand(commandId, command);
+				}
+			});
 	}
 
 	@command('git.refresh')
@@ -288,8 +304,8 @@ export class CommandCenter {
 		return await this.model.add();
 	}
 
-	@command('git.stageSelectedRanges')
-	async stageSelectedRanges(): Promise<void> {
+	@command('git.stageSelectedRanges', false, true)
+	async stageSelectedRanges(diffs: LineChange[]): Promise<void> {
 		const textEditor = window.activeTextEditor;
 
 		if (!textEditor) {
@@ -305,7 +321,6 @@ export class CommandCenter {
 
 		const originalUri = modifiedUri.with({ scheme: 'git', query: '~' });
 		const originalDocument = await workspace.openTextDocument(originalUri);
-		const diffs = await computeDiff(originalDocument, modifiedDocument);
 		const selections = textEditor.selections;
 		const selectedDiffs = diffs.filter(diff => {
 			const modifiedRange = diff.modifiedEndLineNumber === 0
@@ -323,8 +338,8 @@ export class CommandCenter {
 		await this.model.stage(modifiedUri, result);
 	}
 
-	@command('git.revertSelectedRanges')
-	async revertSelectedRanges(): Promise<void> {
+	@command('git.revertSelectedRanges', false, true)
+	async revertSelectedRanges(diffs: LineChange[]): Promise<void> {
 		const textEditor = window.activeTextEditor;
 
 		if (!textEditor) {
@@ -340,7 +355,6 @@ export class CommandCenter {
 
 		const originalUri = modifiedUri.with({ scheme: 'git', query: '~' });
 		const originalDocument = await workspace.openTextDocument(originalUri);
-		const diffs = await computeDiff(originalDocument, modifiedDocument);
 		const selections = textEditor.selections;
 		const selectedDiffs = diffs.filter(diff => {
 			const modifiedRange = diff.modifiedEndLineNumber === 0
@@ -385,8 +399,8 @@ export class CommandCenter {
 		return await this.model.revertFiles();
 	}
 
-	@command('git.unstageSelectedRanges')
-	async unstageSelectedRanges(): Promise<void> {
+	@command('git.unstageSelectedRanges', false, true)
+	async unstageSelectedRanges(diffs: LineChange[]): Promise<void> {
 		const textEditor = window.activeTextEditor;
 
 		if (!textEditor) {
@@ -402,7 +416,6 @@ export class CommandCenter {
 
 		const originalUri = modifiedUri.with({ scheme: 'git', query: 'HEAD' });
 		const originalDocument = await workspace.openTextDocument(originalUri);
-		const diffs = await computeDiff(originalDocument, modifiedDocument);
 		const selections = textEditor.selections;
 		const selectedDiffs = diffs.filter(diff => {
 			const modifiedRange = diff.modifiedEndLineNumber === 0
diff --git a/src/vs/vscode.proposed.d.ts b/src/vs/vscode.proposed.d.ts
index 307de4a1b5c..7c89c247fce 100644
--- a/src/vs/vscode.proposed.d.ts
+++ b/src/vs/vscode.proposed.d.ts
@@ -639,5 +639,22 @@ declare module 'vscode' {
 		readonly modifiedEndLineNumber: number;
 	}
 
-	export function computeDiff(oneDocument: TextDocument, otherDocument: TextDocument): Thenable<LineChange[]>;
-}
+	export namespace commands {
+
+		/**
+		 * Registers a diff information command that can be invoked via a keyboard shortcut,
+		 * a menu item, an action, or directly.
+		 *
+		 * Diff information commands are different from ordinary [commands](#commands.registerCommand) as
+		 * they only execute when there is an active diff editor when the command is called, and the diff
+		 * information has been computed. Also, the command handler of an editor command has access to
+		 * the diff information.
+		 *
+		 * @param command A unique identifier for the command.
+		 * @param callback A command handler function with access to the [diff information](#LineChange).
+		 * @param thisArg The `this` context used when invoking the handler function.
+		 * @return Disposable which unregisters this command on disposal.
+		 */
+		export function registerDiffInformationCommand(command: string, callback: (diff: LineChange[], ...args: any[]) => any, thisArg?: any): Disposable;
+	}
+}
\ No newline at end of file
diff --git a/src/vs/workbench/api/node/extHost.api.impl.ts b/src/vs/workbench/api/node/extHost.api.impl.ts
index 4ce9f9f75c0..9f545cbd710 100644
--- a/src/vs/workbench/api/node/extHost.api.impl.ts
+++ b/src/vs/workbench/api/node/extHost.api.impl.ts
@@ -33,7 +33,6 @@ import { ExtHostEditors } from 'vs/workbench/api/node/extHostTextEditors';
 import { ExtHostLanguages } from 'vs/workbench/api/node/extHostLanguages';
 import { ExtHostLanguageFeatures } from 'vs/workbench/api/node/extHostLanguageFeatures';
 import { ExtHostApiCommands } from 'vs/workbench/api/node/extHostApiCommands';
-import { computeDiff } from 'vs/workbench/api/node/extHostFunctions';
 import { ExtHostTask } from 'vs/workbench/api/node/extHostTask';
 import * as extHostTypes from 'vs/workbench/api/node/extHostTypes';
 import URI from 'vs/base/common/uri';
@@ -167,6 +166,18 @@ export function createApiFactory(initData: IInitData, threadService: IThreadServ
 					});
 				});
 			},
+			registerDiffInformationCommand(id: string, callback: (diff: vscode.LineChange[], ...args: any[]) => any, thisArg?: any): vscode.Disposable {
+				return extHostCommands.registerCommand(id, async (...args: any[]) => {
+					let activeTextEditor = extHostEditors.getActiveTextEditor();
+					if (!activeTextEditor) {
+						console.warn('Cannot execute ' + id + ' because there is no active text editor.');
+						return undefined;
+					}
+
+					const diff = await extHostEditors.getDiffInformation(activeTextEditor.id);
+					callback.apply(thisArg, [diff, ...args]);
+				});
+			},
 			executeCommand<T>(id: string, ...args: any[]): Thenable<T> {
 				return extHostCommands.executeCommand(id, ...args);
 			},
@@ -499,7 +510,6 @@ export function createApiFactory(initData: IInitData, threadService: IThreadServ
 			ViewColumn: extHostTypes.ViewColumn,
 			WorkspaceEdit: extHostTypes.WorkspaceEdit,
 			// functions
-			computeDiff,
 			FileLocationKind: extHostTypes.FileLocationKind,
 			ApplyToKind: extHostTypes.ApplyToKind,
 			RevealKind: extHostTypes.RevealKind,
diff --git a/src/vs/workbench/api/node/extHost.protocol.ts b/src/vs/workbench/api/node/extHost.protocol.ts
index 1f8924d33bf..bda5b5ff0fb 100644
--- a/src/vs/workbench/api/node/extHost.protocol.ts
+++ b/src/vs/workbench/api/node/extHost.protocol.ts
@@ -140,6 +140,7 @@ export abstract class MainThreadEditorsShape {
 	$trySetSelections(id: string, selections: editorCommon.ISelection[]): TPromise<any> { throw ni(); }
 	$tryApplyEdits(id: string, modelVersionId: number, edits: editorCommon.ISingleEditOperation[], opts: IApplyEditsOptions): TPromise<boolean> { throw ni(); }
 	$tryInsertSnippet(id: string, template: string, selections: editorCommon.IRange[], opts: IUndoStopOptions): TPromise<any> { throw ni(); }
+	$getDiffInformation(id: string): TPromise<editorCommon.ILineChange[]> { throw ni(); }
 }
 
 export abstract class MainThreadTreeExplorersShape {
diff --git a/src/vs/workbench/api/node/extHostFunctions.ts b/src/vs/workbench/api/node/extHostFunctions.ts
deleted file mode 100644
index cb21a24ea0e..00000000000
--- a/src/vs/workbench/api/node/extHostFunctions.ts
+++ /dev/null
@@ -1,30 +0,0 @@
-/*---------------------------------------------------------------------------------------------
- *  Copyright (c) Microsoft Corporation. All rights reserved.
- *  Licensed under the MIT License. See License.txt in the project root for license information.
- *--------------------------------------------------------------------------------------------*/
-
-'use strict';
-
-import * as vscode from 'vscode';
-import { toThenable } from 'vs/base/common/async';
-import { DiffComputer } from 'vs/editor/common/diff/diffComputer';
-
-function getTextDocumentLines(document: vscode.TextDocument): string[] {
-	const result = [];
-	for (let i = 0; i < document.lineCount; i++) {
-		result.push(document.lineAt(i).text);
-	}
-	return result;
-}
-
-export function computeDiff(oneDocument: vscode.TextDocument, otherDocument: vscode.TextDocument): Thenable<vscode.LineChange[]> {
-	const oneLines = getTextDocumentLines(oneDocument);
-	const otherLines = getTextDocumentLines(otherDocument);
-	const computer = new DiffComputer(oneLines, otherLines, {
-		shouldPostProcessCharChanges: false,
-		shouldIgnoreTrimWhitespace: false, // options?
-		shouldConsiderTrimWhitespaceInEmptyCase: false
-	});
-
-	return toThenable(computer.computeDiff());
-}
\ No newline at end of file
diff --git a/src/vs/workbench/api/node/extHostTextEditor.ts b/src/vs/workbench/api/node/extHostTextEditor.ts
index 98eedfcbce5..b0f0ec172e6 100644
--- a/src/vs/workbench/api/node/extHostTextEditor.ts
+++ b/src/vs/workbench/api/node/extHostTextEditor.ts
@@ -322,6 +322,8 @@ export class ExtHostTextEditor implements vscode.TextEditor {
 	private _viewColumn: vscode.ViewColumn;
 	private _disposed: boolean = false;
 
+	get id(): string { return this._id; }
+
 	constructor(proxy: MainThreadEditorsShape, id: string, document: ExtHostDocumentData, selections: Selection[], options: IResolvedTextEditorConfiguration, viewColumn: vscode.ViewColumn) {
 		this._proxy = proxy;
 		this._id = id;
diff --git a/src/vs/workbench/api/node/extHostTextEditors.ts b/src/vs/workbench/api/node/extHostTextEditors.ts
index fb4fd75dfd3..db7f7cb4e9c 100644
--- a/src/vs/workbench/api/node/extHostTextEditors.ts
+++ b/src/vs/workbench/api/node/extHostTextEditors.ts
@@ -6,12 +6,13 @@
 
 import URI from 'vs/base/common/uri';
 import Event, { Emitter } from 'vs/base/common/event';
+import { toThenable } from 'vs/base/common/async';
 import { TPromise } from 'vs/base/common/winjs.base';
 import { IThreadService } from 'vs/workbench/services/thread/common/threadService';
 import { TextEditorSelectionChangeKind } from './extHostTypes';
 import { IResolvedTextEditorConfiguration, ISelectionChangeEvent } from 'vs/workbench/api/node/mainThreadEditor';
 import * as TypeConverters from './extHostTypeConverters';
-import { TextEditorDecorationType } from './extHostTextEditor';
+import { TextEditorDecorationType, ExtHostTextEditor } from './extHostTextEditor';
 import { ExtHostDocumentsAndEditors } from './extHostDocumentsAndEditors';
 import { MainContext, MainThreadEditorsShape, ExtHostEditorsShape, ITextEditorPositionData } from './extHost.protocol';
 import * as vscode from 'vscode';
@@ -46,7 +47,7 @@ export class ExtHostEditors extends ExtHostEditorsShape {
 		this._extHostDocumentsAndEditors.onDidChangeActiveTextEditor(e => this._onDidChangeActiveTextEditor.fire(e));
 	}
 
-	getActiveTextEditor(): vscode.TextEditor {
+	getActiveTextEditor(): ExtHostTextEditor {
 		return this._extHostDocumentsAndEditors.activeEditor();
 	}
 
@@ -102,4 +103,8 @@ export class ExtHostEditors extends ExtHostEditorsShape {
 			}
 		}
 	}
+
+	getDiffInformation(id: string): Thenable<vscode.LineChange[]> {
+		return toThenable(this._proxy.$getDiffInformation(id));
+	}
 }
diff --git a/src/vs/workbench/api/node/mainThreadEditors.ts b/src/vs/workbench/api/node/mainThreadEditors.ts
index 9c3833207dd..23d8972ab30 100644
--- a/src/vs/workbench/api/node/mainThreadEditors.ts
+++ b/src/vs/workbench/api/node/mainThreadEditors.ts
@@ -8,7 +8,7 @@ import URI from 'vs/base/common/uri';
 import { IDisposable, dispose } from 'vs/base/common/lifecycle';
 import { TPromise } from 'vs/base/common/winjs.base';
 import { IThreadService } from 'vs/workbench/services/thread/common/threadService';
-import { ISingleEditOperation, ISelection, IRange, IDecorationRenderOptions, IDecorationOptions } from 'vs/editor/common/editorCommon';
+import { ISingleEditOperation, ISelection, IRange, IDecorationRenderOptions, IDecorationOptions, ILineChange } from 'vs/editor/common/editorCommon';
 import { ICodeEditorService } from 'vs/editor/common/services/codeEditorService';
 import { IWorkbenchEditorService } from 'vs/workbench/services/editor/common/editorService';
 import { IEditorGroupService } from 'vs/workbench/services/group/common/groupService';
@@ -200,6 +200,24 @@ export class MainThreadEditors extends MainThreadEditorsShape {
 
 	$removeTextEditorDecorationType(key: string): void {
 		this._codeEditorService.removeDecorationType(key);
+	}
+
+	$getDiffInformation(id: string): TPromise<ILineChange[]> {
+		const editor = this._documentsAndEditors.getEditor(id);
+
+		if (!editor) {
+			return TPromise.wrapError('No such TextEditor');
+		}
+
+		const codeEditor = editor.getCodeEditor();
+		const codeEditorId = codeEditor.getId();
+		const diffEditors = this._codeEditorService.listDiffEditors();
+		const [diffEditor] = diffEditors.filter(d => d.getOriginalEditor().getId() === codeEditorId || d.getModifiedEditor().getId() === codeEditorId);
+
+		if (!diffEditor) {
+			return TPromise.as([]);
+		}
 
+		return TPromise.as(diffEditor.getLineChanges());
 	}
 }
diff --git a/src/vs/workbench/test/node/api/extHostTextEditor.test.ts b/src/vs/workbench/test/node/api/extHostTextEditor.test.ts
index 87e55295017..fdb5aedf62c 100644
--- a/src/vs/workbench/test/node/api/extHostTextEditor.test.ts
+++ b/src/vs/workbench/test/node/api/extHostTextEditor.test.ts
@@ -64,7 +64,8 @@ suite('ExtHostTextEditorOptions', () => {
 			$tryRevealRange: undefined,
 			$trySetSelections: undefined,
 			$tryApplyEdits: undefined,
-			$tryInsertSnippet: undefined
+			$tryInsertSnippet: undefined,
+			$getDiffInformation: undefined
 		};
 		opts = new ExtHostTextEditorOptions(mockProxy, '1', {
 			tabSize: 4,