1 files changed, 64 insertions, 0 deletions
diff --git a/packages/upgrade/src/actions/context.ts b/packages/upgrade/src/actions/context.ts
new file mode 100644
index 000000000..1588eb509
--- /dev/null
+++ b/packages/upgrade/src/actions/context.ts
@@ -0,0 +1,64 @@
+import { pathToFileURL } from 'node:url';
+import { prompt } from '@astrojs/cli-kit';
+import arg from 'arg';
+import { type DetectResult, detect } from 'package-manager-detector';
+
+export interface Context {
+	help: boolean;
+	prompt: typeof prompt;
+	version: string;
+	dryRun?: boolean;
+	cwd: URL;
+	stdin?: typeof process.stdin;
+	stdout?: typeof process.stdout;
+	packageManager: DetectResult;
+	packages: PackageInfo[];
+	exit(code: number): never;
+}
+
+export interface PackageInfo {
+	name: string;
+	currentVersion: string;
+	targetVersion: string;
+	tag?: string;
+	isDevDependency?: boolean;
+	isMajor?: boolean;
+	changelogURL?: string;
+	changelogTitle?: string;
+}
+
+export async function getContext(argv: string[]): Promise<Context> {
+	const flags = arg(
+		{
+			'--dry-run': Boolean,
+			'--help': Boolean,
+
+			'-h': '--help',
+		},
+		{ argv, permissive: true },
+	);
+
+	const packageManager = (await detect({
+		// Include the `install-metadata` strategy to have the package manager that's
+		// used for installation take precedence
+		strategies: ['install-metadata', 'lockfile', 'packageManager-field'],
+	})) ?? { agent: 'npm', name: 'npm' };
+	const {
+		_: [version = 'latest'] = [],
+		'--help': help = false,
+		'--dry-run': dryRun,
+	} = flags;
+
+	return {
+		help,
+		prompt,
+		packageManager,
+		packages: [],
+		cwd: new URL(pathToFileURL(process.cwd()) + '/'),
+		dryRun,
+		version,
+		exit(code) {
+			process.exit(code);
+		},
+	} satisfies Context;
+}