microsoft · mjbvz · Sep 11, 2019 · Sep 6, 2019 · Sep 7, 2019 · Sep 7, 2019
diff --git a/extensions/markdown-language-features/src/docIndex.ts b/extensions/markdown-language-features/src/docIndex.ts
@@ -0,0 +1,50 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import * as vscode from 'vscode';
+import { Disposable } from './util/dispose';
+
+
+export class DocumentIndex extends Disposable {
+	private readonly _uriMap = new Map();
+
+	constructor() {
+		super();
+
+		for (let doc of vscode.workspace.textDocuments) {
+			this._registerDoc(doc);
+		}
+
+		this._register(
+			vscode.workspace.onDidOpenTextDocument((doc) => {
+				this._registerDoc(doc);
+			})
+		);
+		this._register(
+			vscode.workspace.onDidCloseTextDocument((doc) => {
+				this._unregisterDoc(doc.uri);
+			})
+		);
+	}
+
+	getByUri(uri: vscode.Uri): vscode.TextDocument | undefined {
+		return this._uriMap.get(uri.toString());
+	}
+
+	private _registerDoc(doc: vscode.TextDocument) {
+		const uri = doc.uri.toString();
+		if (this._uriMap.has(uri)) {
+			throw new Error(`The document ${uri} is already registered.`);
+		}
+		this._uriMap.set(uri, doc);
+	}
+
+	private _unregisterDoc(uri: vscode.Uri) {
+		if (!this._uriMap.has(uri.toString())) {
+			throw new Error(`The document ${uri.toString()} is not registered.`);
+		}
+		this._uriMap.delete(uri.toString());
+	}
+}
diff --git a/extensions/markdown-language-features/src/features/workspaceSymbolProvider.ts b/extensions/markdown-language-features/src/features/workspaceSymbolProvider.ts
@@ -8,8 +8,9 @@ import { Disposable } from '../util/dispose';
 import { isMarkdownFile } from '../util/file';
 import { Lazy, lazy } from '../util/lazy';
 import MDDocumentSymbolProvider from './documentSymbolProvider';
-import { SkinnyTextDocument } from '../tableOfContentsProvider';
+import { SkinnyTextDocument, SkinnyTextLine } from '../tableOfContentsProvider';
 import { flatten } from '../util/arrays';
+import { DocumentIndex } from '../docIndex';
 
 export interface WorkspaceMarkdownDocumentProvider {
 	getAllMarkdownDocuments(): Thenable<Iterable<SkinnyTextDocument>>;
@@ -26,6 +27,7 @@ class VSCodeWorkspaceMarkdownDocumentProvider extends Disposable implements Work
 	private readonly _onDidDeleteMarkdownDocumentEmitter = this._register(new vscode.EventEmitter<vscode.Uri>());
 
 	private _watcher: vscode.FileSystemWatcher | undefined;
+	private _docIndex: DocumentIndex = this._register(new DocumentIndex());
 
 	async getAllMarkdownDocuments() {
 		const resources = await vscode.workspace.findFiles('**/*.md', '**/node_modules/**');
@@ -81,12 +83,39 @@ class VSCodeWorkspaceMarkdownDocumentProvider extends Disposable implements Work
 	}
 
 	private async getMarkdownDocument(resource: vscode.Uri): Promise<SkinnyTextDocument | undefined> {
-		const doc = await vscode.workspace.openTextDocument(resource);
-		return doc && isMarkdownFile(doc) ? doc : undefined;
+		const existingDocument = this._docIndex.getByUri(resource);
+		if (existingDocument) {
+			return existingDocument;
+		}
+
+		const bytes = await vscode.workspace.fs.readFile(resource);
+
+		// We assume that markdown is in UTF-8
+		const text = Buffer.from(bytes).toString('utf-8');
+
+		const lines: SkinnyTextLine[] = [];
+		const parts = text.split(/(\r?\n)/);
+		const lineCount = Math.floor(parts.length / 2) + 1;
+		for (let line = 0; line < lineCount; line++) {
+			lines.push({
+				text: parts[line * 2]
+			});
+		}
+
+		return Promise.resolve({
+			uri: resource,
+			version: 0,
+			lineCount: lineCount,
+			lineAt: (index) => {
+				return lines[index];
+			},
+			getText: () => {
+				return text;
+			}
+		});
 	}
 }
 
-
 export default class MarkdownWorkspaceSymbolProvider extends Disposable implements vscode.WorkspaceSymbolProvider {
 	private _symbolCache = new Map<string, Lazy<Thenable<vscode.SymbolInformation[]>>>();
 	private _symbolCachePopulated: boolean = false;

diff --git a/extensions/markdown-language-features/src/tableOfContentsProvider.ts b/extensions/markdown-language-features/src/tableOfContentsProvider.ts
@@ -15,12 +15,17 @@ export interface TocEntry {
 	readonly location: vscode.Location;
 }
 
+export interface SkinnyTextLine {
+	text: string;
+}
+
 export interface SkinnyTextDocument {
 	readonly uri: vscode.Uri;
 	readonly version: number;
 	readonly lineCount: number;
+
+	lineAt(line: number): SkinnyTextLine;
 	getText(): string;
-	lineAt(line: number): vscode.TextLine;
 }
 
 export class TableOfContentsProvider {
@@ -72,7 +77,8 @@ export class TableOfContentsProvider {
 				text: TableOfContentsProvider.getHeaderText(line.text),
 				level: TableOfContentsProvider.getHeaderLevel(heading.markup),
 				line: lineNumber,
-				location: new vscode.Location(document.uri, line.range)
+				location: new vscode.Location(document.uri,
+					new vscode.Range(lineNumber, 0, lineNumber, line.text.length))
 			});
 		}
 
@@ -85,13 +91,13 @@ export class TableOfContentsProvider {
 					break;
 				}
 			}
-			const endLine = typeof end === 'number' ? end : document.lineCount - 1;
+			const endLine = end !== undefined ? end : document.lineCount - 1;
 			return {
 				...entry,
 				location: new vscode.Location(document.uri,
 					new vscode.Range(
 						entry.location.range.start,
-						new vscode.Position(endLine, document.lineAt(endLine).range.end.character)))
+						new vscode.Position(endLine, document.lineAt(endLine).text.length)))
 			};
 		});
 	}