Merge pull request #630 from callstack-internal/task/877-refactor-onyx-to-use-for-of-loops

Task/877 refactor onyx to use for of loops

Author: carlosmiceli

lib/Onyx.ts

@@ -40,7 +40,7 @@ function init({
     initialKeyStates = {},
     safeEvictionKeys = [],
     maxCachedKeysCount = 1000,
-    shouldSyncMultipleInstances = Boolean(global.localStorage),
+    shouldSyncMultipleInstances = !!global.localStorage,
     debugSetState = false,
     enablePerformanceMetrics = false,
     skippableCollectionMemberIDs = [],

lib/OnyxCache.ts

@@ -231,10 +231,9 @@ class OnyxCache {
             numKeysToRemove--;
         }
 
-        // eslint-disable-next-line @typescript-eslint/prefer-for-of
-        for (let i = 0; i < temp.length; ++i) {
-            delete this.storageMap[temp[i]];
-            this.recentKeys.delete(temp[i]);
+        for (const key of temp) {
+            delete this.storageMap[key];
+            this.recentKeys.delete(key);
         }
     }
 

lib/OnyxUtils.ts

@@ -1,4 +1,3 @@
-/* eslint-disable @typescript-eslint/prefer-for-of */
 /* eslint-disable no-continue */
 import {deepEqual} from 'fast-equals';
 import lodashClone from 'lodash/clone';
@@ -666,8 +665,9 @@ function keysChanged<TKey extends CollectionKeyBase>(
     // and does not represent all of the combined keys and values for a collection key. It is just the "new" data that was merged in via mergeCollection().
     const stateMappingKeys = Object.keys(callbackToStateMapping);
     const collectionKeyLength = collectionKey.length;
-    for (let i = 0; i < stateMappingKeys.length; i++) {
-        const subscriber = callbackToStateMapping[stateMappingKeys[i]];
+
+    for (const stateMappingKey of stateMappingKeys) {
+        const subscriber = callbackToStateMapping[stateMappingKey];
         if (!subscriber) {
             continue;
         }
@@ -704,9 +704,7 @@ function keysChanged<TKey extends CollectionKeyBase>(
                 // If they are not using waitForCollectionCallback then we notify the subscriber with
                 // the new merged data but only for any keys in the partial collection.
                 const dataKeys = Object.keys(partialCollection ?? {});
-                for (let j = 0; j < dataKeys.length; j++) {
-                    const dataKey = dataKeys[j];
-
+                for (const dataKey of dataKeys) {
                     if (deepEqual(cachedCollection[dataKey], previousCollection[dataKey])) {
                         continue;
                     }
@@ -763,8 +761,7 @@ function keysChanged<TKey extends CollectionKeyBase>(
                     const prevCollection = prevState?.[subscriber.statePropertyName] ?? {};
                     const finalCollection = lodashClone(prevCollection);
                     const dataKeys = Object.keys(partialCollection ?? {});
-                    for (let j = 0; j < dataKeys.length; j++) {
-                        const dataKey = dataKeys[j];
+                    for (const dataKey of dataKeys) {
                         finalCollection[dataKey] = cachedCollection[dataKey];
                     }
 
@@ -883,8 +880,8 @@ function keyChanged<TKey extends OnyxKey>(
 
     const cachedCollections: Record<string, ReturnType<typeof getCachedCollection>> = {};
 
-    for (let i = 0; i < stateMappingKeys.length; i++) {
-        const subscriber = callbackToStateMapping[stateMappingKeys[i]];
+    for (const stateMappingKey of stateMappingKeys) {
+        const subscriber = callbackToStateMapping[stateMappingKey];
         if (!subscriber || !isKeyMatch(subscriber.key, key) || !canUpdateSubscriber(subscriber)) {
             continue;
         }
@@ -1348,7 +1345,7 @@ function subscribeToKey<TKey extends OnyxKey>(connectOptions: ConnectOptions<TKe
             // Performance improvement
             // If the mapping is connected to an onyx key that is not a collection
             // we can skip the call to getAllKeys() and return an array with a single item
-            if (Boolean(mapping.key) && typeof mapping.key === 'string' && !isCollectionKey(mapping.key) && cache.getAllKeys().has(mapping.key)) {
+            if (!!mapping.key && typeof mapping.key === 'string' && !isCollectionKey(mapping.key) && cache.getAllKeys().has(mapping.key)) {
                 return new Set([mapping.key]);
             }
             return getAllKeys();

lib/utils.ts

@@ -1,5 +1,3 @@
-/* eslint-disable @typescript-eslint/prefer-for-of */
-
 import type {ConnectOptions, OnyxInput, OnyxKey} from './types';
 
 type EmptyObject = Record<string, never>;
@@ -154,16 +152,15 @@ function filterObject<TValue>(obj: Record<string, TValue>, condition: string | s
     const result: Record<string, TValue> = {};
     const entries = Object.entries(obj);
 
-    for (let i = 0; i < entries.length; i++) {
-        const [key, value] = entries[i];
+    for (const [key, value] of entries) {
         let shouldInclude: boolean;
 
         if (Array.isArray(condition)) {
             shouldInclude = condition.includes(key);
         } else if (typeof condition === 'string') {
             shouldInclude = key === condition;
         } else {
-            shouldInclude = condition(entries[i]);
+            shouldInclude = condition([key, value]);
         }
 
         if (include ? shouldInclude : !shouldInclude) {