Solved a warn issue with shouldComponentUpdate and PureComponent.

PureComponent cannot be used when declaring shouldComponentUpdate. Changed to React.Component.

index.js

@@ -1,6 +1,6 @@
 /* @flow */
 
-import React, { PureComponent } from 'react'
+import React, { Component } from 'react'
 import { View } from 'react-native'
 import SimpleMarkdown from 'simple-markdown'
 import _ from 'lodash'
@@ -12,58 +12,67 @@ type Props = {
   children?: string,
   rules: Object,
   whitelist: Array,
-  blacklist: Array,
+  blacklist: Array
 }
 
 type DefaultProps = Props & {
-  children: string,
+  children: string
 }
 
-class Markdown extends PureComponent<DefaultProps, Props, void> {
+class Markdown extends Component<DefaultProps, Props, void> {
   static defaultProps = {
     styles: initialStyles,
     children: '',
     rules: {},
     whitelist: [],
-    blacklist: [],
+    blacklist: []
   }
 
   /** Post processes rules to strip out unwanted styling options
     * while keeping the default 'paragraph' and 'text' rules
     */
   _postProcessRules = (preRules: Array<string>): Array<string> => {
-      const defaultRules = ['paragraph', 'text']
-      if (this.props.whitelist.length) {
-        return _.pick(preRules, _.concat(this.props.whitelist, defaultRules))
-      }
-      else if (this.props.blacklist.length) {
-        return _.omit(preRules, _.pullAll(this.props.blacklist, defaultRules))
-      }
-      else {
-        return preRules
-      }
+    const defaultRules = ['paragraph', 'text']
+    if (this.props.whitelist.length) {
+      return _.pick(preRules, _.concat(this.props.whitelist, defaultRules))
+    } else if (this.props.blacklist.length) {
+      return _.omit(preRules, _.pullAll(this.props.blacklist, defaultRules))
+    } else {
+      return preRules
+    }
   }
 
   _renderContent = (children: string): React$Element<any> => {
     try {
       const mergedStyles = Object.assign(initialStyles, this.props.styles)
-      const rules = this._postProcessRules(_.merge({}, SimpleMarkdown.defaultRules, initialRules(mergedStyles), this.props.rules))
+      const rules = this._postProcessRules(
+        _.merge(
+          {},
+          SimpleMarkdown.defaultRules,
+          initialRules(mergedStyles),
+          this.props.rules
+        )
+      )
       const child = Array.isArray(this.props.children)
         ? this.props.children.join('')
         : this.props.children
       const blockSource = child + '\n\n'
-      const tree = SimpleMarkdown.parserFor(rules)(blockSource, { inline: false })
-      return SimpleMarkdown.reactFor(SimpleMarkdown.ruleOutput(rules, 'react'))(tree)
-    } catch(errors) {
+      const tree = SimpleMarkdown.parserFor(rules)(blockSource, {
+        inline: false
+      })
+      return SimpleMarkdown.reactFor(SimpleMarkdown.ruleOutput(rules, 'react'))(
+        tree
+      )
+    } catch (errors) {
       this.props.errorHandler
-        ? this.props.errorHandler(errors,children)
+        ? this.props.errorHandler(errors, children)
         : console.error(errors)
     }
   }
 
-  shouldComponentUpdate = (nextProps: Props): boolean => (
-    this.props.children !== nextProps.children || this.props.styles !== nextProps.styles
-  )
+  shouldComponentUpdate = (nextProps: Props): boolean =>
+    this.props.children !== nextProps.children ||
+    this.props.styles !== nextProps.styles
 
   render() {
     return (
@@ -72,7 +81,6 @@ class Markdown extends PureComponent<DefaultProps, Props, void> {
       </View>
     )
   }
-
 }
 
 export default Markdown