42 lines
1.6 KiB
JavaScript
42 lines
1.6 KiB
JavaScript
"use strict";
|
|
Object.defineProperty(exports, "__esModule", { value: true });
|
|
exports.requireAllProps = requireAllProps;
|
|
/**
|
|
* Helper function to check listed properties according to given type. Check if all properties has been used when object is initialised.
|
|
*
|
|
* Example use:
|
|
*
|
|
* ```ts
|
|
* type SomeType = { propA: string; propB?: number; }
|
|
*
|
|
* // propB has to be mentioned even it is optional. It still should be initialized with undefined.
|
|
* const a: SomeType = requireAllProps<SomeType>({ propA: "value A", propB: undefined });
|
|
*
|
|
* // checked type is implicit for variable.
|
|
* const b = requireAllProps<SomeType>({ propA: "value A", propB: undefined });
|
|
* ```
|
|
*
|
|
* Wrong use of this helper:
|
|
*
|
|
* 1. Omit checked type - all checked properties will be expect as of type never
|
|
*
|
|
* ```ts
|
|
* type SomeType = { propA: string; propB?: number; }
|
|
* // const z: SomeType = requireAllProps({ propC: "no type will work" }); // Property 'propA' is missing in type '{ propC: string; }' but required in type 'SomeType'.
|
|
* ```
|
|
*
|
|
* 2. Apply to spreaded object - there is no way how to check in compile time if spreaded object contains all properties
|
|
*
|
|
* ```ts
|
|
* type SomeType = { propA: string; propB?: number; }
|
|
* const y: SomeType = { propA: "" }; // valid object according to SomeType declaration
|
|
* // const x = requireAllProps<SomeType>({ ...y }); // Argument of type '{ propA: string; propB?: number; }' is not assignable to parameter of type 'AllProps<SomeType>'.
|
|
* ```
|
|
*
|
|
* @param obj object to check if all properties has been used
|
|
* @returns untouched obj parameter is returned
|
|
*/
|
|
function requireAllProps(obj) {
|
|
return obj;
|
|
}
|