Add a Share menu and a share vscode.dev command (#152765)

* Add a share menu
Fixes #146309

* Add vscod.dev command in github extension

* Make share menu proposed

* Add share submenu into editor context

* Add proposed to editor share menu

extensions/github/src/links.ts

@@ -0,0 +1,78 @@
+/*---------------------------------------------------------------------------------------------
+ *  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 { API as GitAPI, Repository } from './typings/git';
+import { getRepositoryFromUrl } from './util';
+
+export function isFileInRepo(repository: Repository, file: vscode.Uri): boolean {
+	return file.path.toLowerCase() === repository.rootUri.path.toLowerCase() ||
+		(file.path.toLowerCase().startsWith(repository.rootUri.path.toLowerCase()) &&
+			file.path.substring(repository.rootUri.path.length).startsWith('/'));
+}
+
+export function getRepositoryForFile(gitAPI: GitAPI, file: vscode.Uri): Repository | undefined {
+	for (const repository of gitAPI.repositories) {
+		if (isFileInRepo(repository, file)) {
+			return repository;
+		}
+	}
+	return undefined;
+}
+
+function getFileAndPosition(): { uri: vscode.Uri | undefined; range: vscode.Range | undefined } {
+	let uri: vscode.Uri | undefined;
+	let range: vscode.Range | undefined;
+	if (vscode.window.activeTextEditor) {
+		uri = vscode.window.activeTextEditor.document.uri;
+		range = vscode.window.activeTextEditor.selection;
+	}
+	return { uri, range };
+}
+
+function rangeString(range: vscode.Range | undefined) {
+	if (!range) {
+		return '';
+	}
+	let hash = `#L${range.start.line + 1}`;
+	if (range.start.line !== range.end.line) {
+		hash += `-L${range.end.line + 1}`;
+	}
+	return hash;
+}
+
+export function getPermalink(gitAPI: GitAPI, hostPrefix?: string): string | undefined {
+	hostPrefix = hostPrefix ?? 'https://github.com';
+	const { uri, range } = getFileAndPosition();
+	if (!uri) {
+		return;
+	}
+	const gitRepo = getRepositoryForFile(gitAPI, uri);
+	if (!gitRepo) {
+		return;
+	}
+	let repo: { owner: string; repo: string } | undefined;
+	gitRepo.state.remotes.find(remote => {
+		if (remote.fetchUrl) {
+			const foundRepo = getRepositoryFromUrl(remote.fetchUrl);
+			if (foundRepo && (remote.name === gitRepo.state.HEAD?.upstream?.remote)) {
+				repo = foundRepo;
+				return;
+			} else if (foundRepo && !repo) {
+				repo = foundRepo;
+			}
+		}
+		return;
+	});
+	if (!repo) {
+		return;
+	}
+
+	const commitHash = gitRepo.state.HEAD?.commit;
+	const pathSegment = uri.path.substring(gitRepo.rootUri.path.length);
+
+	return `${hostPrefix}/${repo.owner}/${repo.repo}/blob/${commitHash
+		}${pathSegment}${rangeString(range)}`;
+}