guardz
Version:
A simple and lightweight TypeScript type guard library for runtime type validation.
61 lines (60 loc) • 2.43 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.isObjectWithEachItem = isObjectWithEachItem;
const generateTypeGuardError_1 = require("./generateTypeGuardError");
/**
* Creates a type guard that checks if a value is a plain object where each property value matches a specific type.
*
* This is a higher-order function that takes a type guard for the property values and returns
* a type guard for objects containing those values. Only checks enumerable own properties.
*
* @param predicate - The type guard function to apply to each property value
* @returns A type guard function that checks if the value is an object with valid property values
*
* @example
* ```typescript
* import { isObjectWithEachItem, isString, isNumber } from 'guardz';
*
* const isStringRecord = isObjectWithEachItem(isString);
* const isNumberRecord = isObjectWithEachItem(isNumber);
*
* console.log(isStringRecord({ a: "hello", b: "world" })); // true
* console.log(isStringRecord({})); // true (empty object is valid)
* console.log(isStringRecord({ a: "hello", b: 123 })); // false (mixed types)
* console.log(isStringRecord([])); // false (array is not a plain object)
* console.log(isStringRecord(null)); // false
*
* // With type narrowing
* const data: unknown = getUserInput();
* if (isStringRecord(data)) {
* // data is now typed as Record<string, string>
* Object.keys(data).forEach(key => {
* console.log(data[key].toUpperCase());
* });
* }
* ```
*/
function isObjectWithEachItem(predicate) {
return function (value, config) {
// Stricter check for plain objects
const isPlainObject = typeof value === 'object' &&
value !== null &&
!Array.isArray(value) &&
value.constructor === Object;
if (!isPlainObject) {
if (config) {
config.callbackOnError((0, generateTypeGuardError_1.generateTypeGuardError)(value, config.identifier, 'Object'));
}
return false;
}
// Cast value to Record<string, unknown> for Object.values compatibility if needed by strict checks
const obj = value;
return Object.values(obj).every((item, index // Use obj here
) => predicate(item, config
? {
...config,
identifier: `${config.identifier}[${index}]`,
}
: null));
};
}