@augment-vir/common/dist/augments/selection-set/select-from.js

A collection of augments, helpers types, functions, and classes for any JavaScript environment.

import { check } from '@augment-vir/assert';
import { mapObjectValues } from '../object/map-values.js';
import { omitObjectKeys } from '../object/object-keys.js';
/**
 * Determine if the given input should be preserved in the selection output, meaning it won't be
 * recursed into.
 *
 * @ignore
 */
export function shouldPreserveInSelectionSet(input) {
    return check.isPrimitive(input) || input instanceof RegExp || input instanceof Promise;
}
/**
 * Performs a SQL-like nested selection on an object, extracting the selected values.
 *
 * @category Selection
 * @category Package : @augment-vir/common
 * @example
 *
 * ```ts
 * import {selectFrom} from '@augment-vir/common';
 *
 * selectFrom(
 *     [
 *         {
 *             child: {
 *                 grandChild: 'hi',
 *                 grandChild2: 3,
 *                 grandChild3: /something/,
 *             },
 *         },
 *         {
 *             child: {
 *                 grandChild: 'hi',
 *                 grandChild2: 4,
 *                 grandChild3: /something/,
 *             },
 *         },
 *     ],
 *     {
 *         child: {
 *             grandChild2: true,
 *         },
 *     },
 * );
 * // output is `[{child: {grandChild2: 3}}, {child: {grandChild2: 4}}]`
 * ```
 *
 * @package [`@augment-vir/common`](https://www.npmjs.com/package/@augment-vir/common)
 */
export function selectFrom(originalObject, selectionSet) {
    if (Array.isArray(originalObject)) {
        return originalObject.map((originalEntry) => selectFrom(originalEntry, selectionSet));
    }
    const keysToRemove = [];
    return omitObjectKeys(mapObjectValues(originalObject, (key, value) => {
        const selection = selectionSet[key];
        if (selection === true) {
            return value;
        }
        else if (!selection) {
            keysToRemove.push(key);
            return undefined;
        }
        else if (shouldPreserveInSelectionSet(value)) {
            return value;
        }
        else {
            return selectFrom(value, selection);
        }
    }), keysToRemove);
}