@applicaster/zapp-react-native-utils/equalUtils/index.ts

Applicaster Zapp React Native utilities package

/* eslint no-console: off */

import { equals } from "ramda";

const alwaysTrue = () => true;

export const isParentFocusEqual = (
  prevParentFocus: ParentFocus,
  nextParentFocus: ParentFocus
): boolean => {
  return (
    prevParentFocus.nextFocusUp === nextParentFocus.nextFocusUp &&
    prevParentFocus.nextFocusDown === nextParentFocus.nextFocusDown &&
    prevParentFocus.nextFocusRight === nextParentFocus.nextFocusRight &&
    prevParentFocus.nextFocusLeft === nextParentFocus.nextFocusLeft
  );
};

export const isEqual =
  ({
    byValue = [],
    byReference = [],
    byComparator = { comparator: alwaysTrue, keys: [] },
    debug = false,
    compareRemainingKeysBySameValue = false,
  }: {
    byValue?: string[];
    byReference?: string[];
    byComparator?: { comparator: (a: any, b: any) => boolean; keys: string[] };
    debug?: boolean;
    compareRemainingKeysBySameValue?: boolean;
  }) =>
  (prev, next) => {
    for (const key of byReference) {
      if (prev[key] !== next[key]) {
        if (debug) console.log({ isEqualByReference: false });

        return false;
      }
    }

    for (const key of byValue) {
      if (!equals(prev[key], next[key])) {
        if (debug) console.log({ isEqualByValue: false });

        return false;
      }
    }

    for (const key of byComparator.keys) {
      if (!byComparator.comparator(prev[key], next[key])) {
        if (debug) console.log({ isEqualByComparator: false });

        return false;
      }
    }

    if (compareRemainingKeysBySameValue) {
      const allKeys = new Set([...Object.keys(prev), ...Object.keys(next)]);

      const declaredKeys = new Set([
        ...byValue,
        ...byReference,
        ...byComparator.keys,
      ]);

      for (const key of Array.from(allKeys)) {
        if (!declaredKeys.has(key) && !Object.is(prev[key], next[key])) {
          if (debug) console.log({ isRestKeysEqualAllBySameValue: false });

          return false;
        }
      }
    }

    // if we made it here, everything matched
    if (debug) {
      console.log({
        isEqualByValue: true,
        isEqualByReference: true,
        isEqualByComparator: true,
        isRestKeysEqualAllBySameValue: compareRemainingKeysBySameValue
          ? true
          : undefined,
      });
    }

    return true;
  };