From a17240466aa6306e84a61e6643059d0d1a0c0158 Mon Sep 17 00:00:00 2001
From: Alexander Zinchuk <alx.zinchuk@gmail.com>
Date: Sun, 9 May 2021 02:00:00 +0300
Subject: [PATCH] [Debug] Some more debug tools

---
 src/lib/teact/teact.ts           | 33 ++++++++++++++++++++++++++++++--
 src/lib/teact/teactn.tsx         | 18 ++++-------------
 src/util/arePropsShallowEqual.ts | 12 ++++++++++++
 3 files changed, 47 insertions(+), 16 deletions(-)

diff --git a/src/lib/teact/teact.ts b/src/lib/teact/teact.ts
index 87066357d..8c2b71cc1 100644
--- a/src/lib/teact/teact.ts
+++ b/src/lib/teact/teact.ts
@@ -3,12 +3,15 @@ import {
   fastRaf, onTickEnd, throttleWithPrimaryRaf, throttleWithRaf,
 } from '../../util/schedulers';
 import { flatten, orderBy } from '../../util/iteratees';
-import arePropsShallowEqual from '../../util/arePropsShallowEqual';
+import arePropsShallowEqual, { getUnequalProps } from '../../util/arePropsShallowEqual';
 import { handleError } from '../../util/handleError';
 import { removeAllDelegatedListeners } from './dom-events';
 
 export type Props = AnyLiteral;
 export type FC<P extends Props = any> = (props: P) => any;
+export type FC_withDebug = FC & {
+  DEBUG_contentComponentName?: string;
+};
 
 export enum VirtualElementTypesEnum {
   Empty,
@@ -444,6 +447,10 @@ export function useState<T>(initial?: T): [T, StateHookSetter<T>] {
       value: initial,
       nextValue: initial,
       setter: ((componentInstance) => (newValue: ((current: T) => T) | T) => {
+        if (!componentInstance.isMounted) {
+          return;
+        }
+
         if (byCursor[cursor].nextValue !== newValue) {
           byCursor[cursor].nextValue = typeof newValue === 'function'
             ? (newValue as (current: T) => T)(byCursor[cursor].value)
@@ -454,6 +461,20 @@ export function useState<T>(initial?: T): [T, StateHookSetter<T>] {
             componentInstance.forceUpdate = throttleWithRaf(() => forceUpdateComponent(componentInstance));
           }
 
+          if (DEBUG_MORE) {
+            // eslint-disable-next-line no-console
+            console.log(
+              '[Teact.useState]',
+              componentInstance.name,
+              // eslint-disable-next-line max-len
+              (componentInstance.Component as FC_withDebug).DEBUG_contentComponentName
+                ? `> ${(componentInstance.Component as FC_withDebug).DEBUG_contentComponentName}`
+                : '',
+              `Forced update at cursor #${cursor}, next value: `,
+              byCursor[cursor].nextValue,
+            );
+          }
+
           componentInstance.scheduleNextState();
           componentInstance.forceUpdate();
         }
@@ -556,13 +577,21 @@ export function useRef<T>(initial?: T | null) {
   }), []);
 }
 
-export function memo<T extends FC>(Component: T, areEqual = arePropsShallowEqual) {
+export function memo<T extends FC>(Component: T, areEqual = arePropsShallowEqual, withDebug = false) {
   return function TeactMemoWrapper(props: Props) {
     // eslint-disable-next-line react-hooks/rules-of-hooks
     const propsRef = useRef(props);
     const renderedRef = useRef();
 
     if (!renderedRef.current || (propsRef.current && !areEqual(propsRef.current, props))) {
+      if (DEBUG && withDebug) {
+        // eslint-disable-next-line no-console
+        console.log(
+          `[Teact.memo] ${Component.name}: Update is caused by:`,
+          getUnequalProps(propsRef.current!, props).join(', '),
+        );
+      }
+
       propsRef.current = props;
       renderedRef.current = createElement(Component, props) as VirtualElementComponent;
     }
diff --git a/src/lib/teact/teactn.tsx b/src/lib/teact/teactn.tsx
index 2d910855f..1b003db8b 100644
--- a/src/lib/teact/teactn.tsx
+++ b/src/lib/teact/teactn.tsx
@@ -1,12 +1,12 @@
 import React, {
-  FC, Props, useEffect, useState,
+  FC, FC_withDebug, Props, useEffect, useState,
 } from './teact';
 
 import { DEBUG, DEBUG_MORE } from '../../config';
 import useForceUpdate from '../../hooks/useForceUpdate';
 import generateIdFor from '../../util/generateIdFor';
 import { throttleWithRaf } from '../../util/schedulers';
-import arePropsShallowEqual from '../../util/arePropsShallowEqual';
+import arePropsShallowEqual, { getUnequalProps } from '../../util/arePropsShallowEqual';
 import { orderBy } from '../../util/iteratees';
 import { GlobalState, GlobalActions, ActionTypes } from '../../global/types';
 import { handleError } from '../../util/handleError';
@@ -164,6 +164,8 @@ export function withGlobal<OwnProps>(
 ) {
   return (Component: FC) => {
     return function TeactNContainer(props: OwnProps) {
+      (TeactNContainer as FC_withDebug).DEBUG_contentComponentName = Component.name;
+
       const [id] = useState(generateIdFor(containers));
       const forceUpdate = useForceUpdate();
 
@@ -211,18 +213,6 @@ export function withGlobal<OwnProps>(
   };
 }
 
-function getUnequalProps(currentProps: AnyLiteral, newProps: AnyLiteral) {
-  const currentKeys = Object.keys(currentProps);
-  const currentKeysLength = currentKeys.length;
-  const newKeysLength = Object.keys(newProps).length;
-
-  if (currentKeysLength !== newKeysLength) {
-    return ['LENGTH'];
-  }
-
-  return currentKeys.filter((prop) => currentProps[prop] !== newProps[prop]);
-}
-
 if (DEBUG) {
   (window as any).getGlobal = getGlobal;
 
diff --git a/src/util/arePropsShallowEqual.ts b/src/util/arePropsShallowEqual.ts
index 0568e8269..ac702087b 100644
--- a/src/util/arePropsShallowEqual.ts
+++ b/src/util/arePropsShallowEqual.ts
@@ -24,3 +24,15 @@ export default function arePropsShallowEqual(currentProps: AnyLiteral, newProps:
 
   return true;
 }
+
+export function getUnequalProps(currentProps: AnyLiteral, newProps: AnyLiteral) {
+  const currentKeys = Object.keys(currentProps);
+  const currentKeysLength = currentKeys.length;
+  const newKeysLength = Object.keys(newProps).length;
+
+  if (currentKeysLength !== newKeysLength) {
+    return ['%LENGTH%'];
+  }
+
+  return currentKeys.filter((prop) => currentProps[prop] !== newProps[prop]);
+}