Intlayer

type Primitive = string | number | boolean | null | undefined; type Recursive = Primitive | { [key: string]: Recursive } | Array<Recursive>; /** * Reduce an object to only the shape provided by a format object. * Values are always taken from the source object; the format is used only for structure. * * Examples: * reduceObjectFormat({ a: 1, b: 2 }, { a: 0 }) => { a: 1 } * reduceObjectFormat({ a: { x: 1, y: 2 } }, { a: { x: 0 } }) => { a: { x: 1 } } */ export const reduceObjectFormat = ( source: Recursive, format: Recursive ): Recursive => { // If the format is an array, reduce each element by its counterpart in source if (Array.isArray(format)) { const sourceArray = Array.isArray(source) ? source : []; return format.map((formatItem, index) => reduceObjectFormat(sourceArray[index], formatItem) ); } // If the format is an object (and not null), pick matching keys and recurse if (typeof format === 'object' && format !== null) { const result: Record<string, Recursive> = {}; const sourceObject = typeof source === 'object' && source !== null && !Array.isArray(source) ? (source as Record<string, Recursive>) : ({} as Record<string, Recursive>); for (const key of Object.keys(format)) { const nextSource = sourceObject[key]; const nextFormat = (format as Record<string, Recursive>)[key]; result[key] = reduceObjectFormat(nextSource, nextFormat); } return result; } // For primitives in the format, simply return the source value (can be undefined) return source as Primitive; };