symbols-mcp

/** * Expands environment variables in a string. * Supports both ${VAR} and $VAR syntax (case-insensitive). * * @param str - String to expand * @param env - Environment object to use for expansion (defaults to process.env) * @returns Expanded string with environment variables replaced * * @example * expandEnvVars('$HOME/.config', process.env) // '/Users/john/.config' * expandEnvVars('${USER}_file', process.env) // 'john_file' */ export function expandEnvVars( str: string, env: NodeJS.ProcessEnv = process.env ): string { return str.replace( /\$\{([^}]+)\}|\$([A-Za-z_][A-Za-z0-9_]*)/g, (match: string, braced: string, simple: string) => { const varName = braced || simple; const value = env[varName]; return value !== undefined ? value : match; } ); }