chore: import upstream snapshot with attribution

extensions/github-authentication/src/common/env.ts

@@ -0,0 +1,38 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+import { Uri } from 'vscode';
+import { AuthProviderType } from '../github';
+
+const VALID_DESKTOP_CALLBACK_SCHEMES = [
+	'vscode',
+	'vscode-insiders',
+	// On Windows, some browsers don't seem to redirect back to OSS properly.
+	// As a result, you get stuck in the auth flow. We exclude this from the
+	// list until we can figure out a way to fix this behavior in browsers.
+	// 'code-oss',
+	'vscode-wsl',
+	'vscode-exploration'
+];
+
+export function isSupportedClient(uri: Uri): boolean {
+	return (
+		VALID_DESKTOP_CALLBACK_SCHEMES.includes(uri.scheme) ||
+		// vscode.dev & insiders.vscode.dev
+		/(?:^|\.)vscode\.dev$/.test(uri.authority) ||
+		// github.dev & codespaces
+		/(?:^|\.)github\.dev$/.test(uri.authority)
+	);
+}
+
+export function isSupportedTarget(type: AuthProviderType, gheUri?: Uri): boolean {
+	return (
+		type === AuthProviderType.github ||
+		isHostedGitHubEnterprise(gheUri!)
+	);
+}
+
+export function isHostedGitHubEnterprise(uri: Uri): boolean {
+	return /\.ghe\.com$/.test(uri.authority);
+}