first cut of tab completion, #9286

src/vs/editor/browser/editor.all.ts

@@ -33,6 +33,7 @@ import 'vs/editor/contrib/rename/browser/rename';
 import 'vs/editor/contrib/smartSelect/common/smartSelect';
 import 'vs/editor/contrib/smartSelect/common/jumpToBracket';
 import 'vs/editor/contrib/snippet/common/snippet';
+import 'vs/editor/contrib/snippet/common/tabCompletion';
 import 'vs/editor/contrib/snippet/browser/snippet';
 import 'vs/editor/contrib/suggest/browser/suggest';
 import 'vs/editor/contrib/toggleTabFocusMode/common/toggleTabFocusMode';

src/vs/editor/common/modes/supports.ts

@@ -217,5 +217,31 @@ export class SnippetsRegistry {
 
 	}
 
+	public static getSnippetsStrict(model: IReadOnlyModel, position: IPosition): modes.ISuggestion[] {
+		const match = model.getLineContent(position.lineNumber).substr(0, position.column - 1).match(/[^\s]+$/);
+		if (!match) {
+			return [];
+		}
+		const prefix = match[0];
+		const result: modes.ISuggestion[] = [];
+		SnippetsRegistry._fillInSuggestion(this._defaultSnippets[model.getModeId()], prefix, result);
+		let snipppetsByMode = this._snippets[model.getModeId()];
+		if (snipppetsByMode) {
+			for (let path in snipppetsByMode) {
+				SnippetsRegistry._fillInSuggestion(snipppetsByMode[path], prefix, result);
+			}
+		}
+		return result;
+	}
 
+	private static _fillInSuggestion(suggestions: modes.ISuggestion[], prefix: string, bucket: modes.ISuggestion[]): void {
+		if (!suggestions) {
+			return;
+		}
+		for (const suggestion of suggestions) {
+			if (strings.endsWith(prefix, suggestion.label)) {
+				bucket.push(suggestion);
+			}
+		}
+	}
 }

src/vs/editor/contrib/snippet/common/tabCompletion.ts

+/*---------------------------------------------------------------------------------------------
+ *  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 {KeyCode} from 'vs/base/common/keyCodes';
+import {IKeybindingService} from 'vs/platform/keybinding/common/keybinding';
+import {KeybindingsRegistry} from 'vs/platform/keybinding/common/keybindingsRegistry';
+import {SnippetsRegistry} from 'vs/editor/common/modes/supports';
+import {ISuggestion} from 'vs/editor/common/modes';
+import {IDisposable} from 'vs/base/common/lifecycle';
+import * as editor from 'vs/editor/common/editorCommon';
+import {CommonEditorRegistry} from 'vs/editor/common/editorCommonExtensions';
+import {CodeSnippet, ISnippetController, getSnippetController} from 'vs/editor/contrib/snippet/common/snippet';
+
+class TabCompletionController implements editor.IEditorContribution {
+
+	static Id = 'editor.tabCompletionController';
+	static ContextKey = 'hasSnippetCompletions';
+
+	private _snippetController: ISnippetController;
+	private _cursorChangeSubscription: IDisposable;
+	private _currentCompletions: ISuggestion[] = [];
+
+	constructor(
+		editor: editor.ICommonCodeEditor,
+		@IKeybindingService keybindingService: IKeybindingService
+	) {
+		this._snippetController = getSnippetController(editor);
+		const hasSnippets = keybindingService.createKey(TabCompletionController.ContextKey, undefined);
+		this._cursorChangeSubscription = editor.onDidChangeCursorPosition(e => {
+			this._currentCompletions.length = 0;
+			this._currentCompletions = SnippetsRegistry.getSnippetsStrict(editor.getModel(), editor.getPosition());
+			hasSnippets.set(this._currentCompletions.length === 1); //todo@joh make it work with N
+		});
+	}
+
+	dispose(): void {
+		this._cursorChangeSubscription.dispose();
+	}
+
+	performSnippetCompletions(): void {
+		if (this._currentCompletions.length === 1) {
+			const suggestion = this._currentCompletions[0];
+			const snippet = new CodeSnippet(suggestion.codeSnippet);
+			this._snippetController.run(snippet, suggestion.label.length, 0);
+		} else {
+			// todo@joh - show suggest widget with proposals
+		}
+	}
+
+	getId(): string {
+		return TabCompletionController.Id;
+	}
+}
+
+CommonEditorRegistry.registerEditorContribution(TabCompletionController);
+CommonEditorRegistry.registerEditorCommand(
+	'tabCompletion',
+	KeybindingsRegistry.WEIGHT.editorContrib(),
+	{ primary: KeyCode.Tab },
+	true,
+	TabCompletionController.ContextKey,
+	(accessor, editor) => {
+		const controller = <TabCompletionController>editor.getContribution(TabCompletionController.Id);
+		controller.performSnippetCompletions();
+	});