Change name of setState updater first arg to 'state' (reactjs#1155)

Author: mmcgahan

content/docs/conditional-rendering.md

@@ -215,8 +215,8 @@ class Page extends React.Component {
   }
 
   handleToggleClick() {
-    this.setState(prevState => ({
-      showWarning: !prevState.showWarning
+    this.setState(state => ({
+      showWarning: !state.showWarning
     }));
   }
 

content/docs/faq-state.md

@@ -59,9 +59,9 @@ Passing an update function allows you to access the current state value inside t
 
 ```jsx
 incrementCount() {
-  this.setState((prevState) => {
-    // Important: read `prevState` instead of `this.state` when updating.
-    return {count: prevState.count + 1}
+  this.setState((state) => {
+    // Important: read `state` instead of `this.state` when updating.
+    return {count: state.count + 1}
   });
 }
 

content/docs/handling-events.md

@@ -71,8 +71,8 @@ class Toggle extends React.Component {
   }
 
   handleClick() {
-    this.setState(prevState => ({
-      isToggleOn: !prevState.isToggleOn
+    this.setState(state => ({
+      isToggleOn: !state.isToggleOn
     }));
   }
 

content/docs/optimizing-performance.md

@@ -339,8 +339,8 @@ The simplest way to avoid this problem is to avoid mutating values that you are
 
 ```javascript
 handleClick() {
-  this.setState(prevState => ({
-    words: prevState.words.concat(['marklar'])
+  this.setState(state => ({
+    words: state.words.concat(['marklar'])
   }));
 }
 ```
@@ -349,8 +349,8 @@ ES6 supports a [spread syntax](https://developer.mozilla.org/en-US/docs/Web/Java
 
 ```js
 handleClick() {
-  this.setState(prevState => ({
-    words: [...prevState.words, 'marklar'],
+  this.setState(state => ({
+    words: [...state.words, 'marklar'],
   }));
 };
 ```

content/docs/portals.md

@@ -113,8 +113,8 @@ class Parent extends React.Component {
     // This will fire when the button in Child is clicked,
     // updating Parent's state, even though button
     // is not direct descendant in the DOM.
-    this.setState(prevState => ({
-      clicks: prevState.clicks + 1
+    this.setState(state => ({
+      clicks: state.clicks + 1
     }));
   }
 

content/docs/reference-react-component.md

@@ -428,18 +428,18 @@ Think of `setState()` as a *request* rather than an immediate command to update
 The first argument is an `updater` function with the signature:
 
 ```javascript
-(prevState, props) => stateChange
+(state, props) => stateChange
 ```
 
-`prevState` is a reference to the previous state. It should not be directly mutated. Instead, changes should be represented by building a new object based on the input from `prevState` and `props`. For instance, suppose we wanted to increment a value in state by `props.step`:
+`state` is a reference to the component state at the time the change is being applied. It should not be directly mutated. Instead, changes should be represented by building a new object based on the input from `state` and `props`. For instance, suppose we wanted to increment a value in state by `props.step`:
 
 ```javascript
-this.setState((prevState, props) => {
-  return {counter: prevState.counter + props.step};
+this.setState((state, props) => {
+  return {counter: state.counter + props.step};
 });
 ```
 
-Both `prevState` and `props` received by the updater function are guaranteed to be up-to-date. The output of the updater is shallowly merged with `prevState`.
+Both `state` and `props` received by the updater function are guaranteed to be up-to-date. The output of the updater is shallowly merged with `state`.
 
 The second parameter to `setState()` is an optional callback function that will be executed once `setState` is completed and the component is re-rendered. Generally we recommend using `componentDidUpdate()` for such logic instead.
 
@@ -466,11 +466,11 @@ Object.assign(
 )
 ```
 
-Subsequent calls will override values from previous calls in the same cycle, so the quantity will only be incremented once. If the next state depends on the previous state, we recommend using the updater function form, instead:
+Subsequent calls will override values from previous calls in the same cycle, so the quantity will only be incremented once. If the next state depends on the current state, we recommend using the updater function form, instead:
 
 ```js
-this.setState((prevState) => {
-  return {quantity: prevState.quantity + 1};
+this.setState((state) => {
+  return {quantity: state.quantity + 1};
 });
 ```
 

content/docs/state-and-lifecycle.md

@@ -359,18 +359,18 @@ To fix it, use a second form of `setState()` that accepts a function rather than
 
 ```js
 // Correct
-this.setState((prevState, props) => ({
-  counter: prevState.counter + props.increment
+this.setState((state, props) => ({
+  counter: state.counter + props.increment
 }));
 ```
 
 We used an [arrow function](https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Functions/Arrow_functions) above, but it also works with regular functions:
 
 ```js
 // Correct
-this.setState(function(prevState, props) {
+this.setState(function(state, props) {
   return {
-    counter: prevState.counter + props.increment
+    counter: state.counter + props.increment
   };
 });
 ```

content/home/examples/a-stateful-component.js

@@ -5,8 +5,8 @@ class Timer extends React.Component {
   }
 
   tick() {
-    this.setState(prevState => ({
-      seconds: prevState.seconds + 1
+    this.setState(state => ({
+      seconds: state.seconds + 1
     }));
   }
 

content/home/examples/an-application.js

@@ -41,8 +41,8 @@ class TodoApp extends React.Component {
       text: this.state.text,
       id: Date.now()
     };
-    this.setState(prevState => ({
-      items: prevState.items.concat(newItem),
+    this.setState(state => ({
+      items: state.items.concat(newItem),
       text: ''
     }));
   }