Function updateEnvVariable

scripts/setup/envFileManager.ts:182–256

(
	config: Record<string, string | number | undefined>,
	options: UpdateEnvOptions = {},
)

}

export async function updateEnvVariable(
	config: Record<string, string | number | undefined>,
	options: UpdateEnvOptions = {},
): Promise<void> {
	const { envFile, backupFile, tempFile } = resolvePaths(options);
	const createBackup = options.createBackup ?? false;
	const restoreFromBackup = options.restoreFromBackup ?? false;

	try {
		const appliedEntries = Object.entries(config).filter(
			(entry): entry is [string, string | number] => entry[1] !== undefined,
		);
		if (appliedEntries.length === 0) {
			return;
		}

		const existingText = await readEnv(envFile);
		const parsedEnv = dotenv.parse(existingText);

		let changed = false;
		for (const [key, rawValue] of appliedEntries) {
			const value = String(rawValue);
			if (parsedEnv[key] !== value) {
				parsedEnv[key] = value;
				changed = true;
			}
			// Intentionally sync the running process environment for every key in
			// `appliedEntries`, even when `parsedEnv` already matches and `changed`
			// stays false (no file rewrite). We may return early on the no-op path,
			// but callers still expect `process.env` to reflect the effective env
			// state represented by `parsedEnv`.
			process.env[key] = value;
		}

		// Preserve the existing file (and its formatting/comments) when the update
		// results in no changes.
		if (!changed) {
			return;
		}

		if (createBackup) {
			await ensureBackup(envFile, backupFile);
		}

		// When we do have changes, we intentionally rewrite the file in a canonical
		// format (dotenv.parse + serialize). This will drop comments/blank lines.
		const nextContent = serializeEnvVars(parsedEnv);
		await writeTemp(tempFile, nextContent);
		await commitTemp(envFile, tempFile);
	} catch (e: unknown) {
		await cleanupTemp(tempFile);
		if (restoreFromBackup) {
			try {
				await restoreBackup(envFile, backupFile);
			} catch (restoreErr: unknown) {
				throw new SetupError(
					SetupErrorCode.RESTORE_FAILED,
					"Update failed and backup restoration also failed",