EuiErrorBoundary: converted to Typescript

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 - Converted `EuiFieldPassword` to Typescript ([#2683](https://github.com/elastic/eui/pull/2683))
 - Converted `EuiHighlight` to Typescript ([#2681](https://github.com/elastic/eui/pull/2681))
+- Converted `EuiErroBoundary` to Typescript  ([#2690](https://github.com/elastic/eui/pull/2690))
 - Converted `EuiTextArea` to Typescript ([#2695](https://github.com/elastic/eui/pull/2695))
 - Converted `EuiPage` and related child components to  TypeScript ([#2669](https://github.com/elastic/eui/pull/2669))
 

src/components/error_boundary/error_boundary.test.js → src/components/error_boundary/error_boundary.test.tsx

@@ -17,7 +17,7 @@ describe('EuiErrorBoundary', () => {
   test('is rendered without an error', () => {
     const component = takeMountedSnapshot(
       mount(
-        <EuiErrorBoundary {...requiredProps}>
+        <EuiErrorBoundary {...requiredProps} hasError={false}>
           <GoodComponent />
         </EuiErrorBoundary>
       )
@@ -33,7 +33,10 @@ describe('EuiErrorBoundary', () => {
     // Because the error contains the stack trace, it's non-deterministic. So we'll just check that
     // it contains our error message.
     const errorText = mount(
-      <EuiErrorBoundary {...requiredProps}>
+      <EuiErrorBoundary
+        {...requiredProps}
+        error={new Error(errorMessage)}
+        hasError={true}>
         <BadComponent />
       </EuiErrorBoundary>
     ).text();

src/components/error_boundary/error_boundary.js → src/components/error_boundary/error_boundary.tsx

@@ -1,23 +1,40 @@
 import React, { Component } from 'react';
+import { CommonProps } from '../common';
 import PropTypes from 'prop-types';
 
 import { EuiText } from '../text';
 
-export class EuiErrorBoundary extends Component {
+interface Error {
+  stack?: any;
+}
+
+interface EuiErrorBoundaryState {
+  hasError: boolean;
+  error?: Error;
+}
+
+export type EuiErrorBoundaryProps = EuiErrorBoundaryState & CommonProps & {};
+
+export class EuiErrorBoundary extends Component<
+  EuiErrorBoundaryProps,
+  EuiErrorBoundaryState
+> {
   static propTypes = {
     children: PropTypes.node,
   };
 
-  constructor(props) {
+  constructor(props: EuiErrorBoundaryProps) {
     super(props);
 
-    this.state = {
+    const errorState: EuiErrorBoundaryState = {
       hasError: false,
       error: undefined,
     };
+
+    this.state = errorState;
   }
 
-  componentDidCatch(error) {
+  componentDidCatch(error: Error) {
     // Display fallback UI
     this.setState({
       hasError: true,