fix(TS): help typescript to find his way for the ErrorBoundaryProps u…

…nion (#90)

This fixes a lot of issue concerning the union and ensures typescript which is which

src/__tests__/hook.tsx

@@ -49,7 +49,7 @@ test('handleError forwards along async errors', async () => {
     "The above error occurred in the <AsyncBomb> component:
 
         at AsyncBomb (<PROJECT_ROOT>/src/__tests__/hook.tsx:21:41)
-        at ErrorBoundary (<PROJECT_ROOT>/src/index.tsx:66:3)
+        at ErrorBoundary (<PROJECT_ROOT>/src/index.tsx:72:3)
 
     React will try to recreate this component tree from scratch using the error boundary you provided, ErrorBoundary."
   `)
@@ -95,7 +95,7 @@ test('can pass an error to useErrorHandler', async () => {
     "The above error occurred in the <AsyncBomb> component:
 
         at AsyncBomb (<PROJECT_ROOT>/src/__tests__/hook.tsx:66:37)
-        at ErrorBoundary (<PROJECT_ROOT>/src/index.tsx:66:3)
+        at ErrorBoundary (<PROJECT_ROOT>/src/index.tsx:72:3)
 
     React will try to recreate this component tree from scratch using the error boundary you provided, ErrorBoundary."
   `)

src/__tests__/index.tsx

@@ -57,7 +57,7 @@ test('standard use-case', () => {
     "The above error occurred in the <Bomb> component:
 
         at Bomb (<PROJECT_ROOT>/src/__tests__/index.tsx:18:9)
-        at ErrorBoundary (<PROJECT_ROOT>/src/index.tsx:66:3)
+        at ErrorBoundary (<PROJECT_ROOT>/src/index.tsx:72:3)
         at div
         at div
         at App (<PROJECT_ROOT>/src/__tests__/index.tsx:28:43)
@@ -162,7 +162,7 @@ test('withErrorBoundary HOC', () => {
     "The above error occurred in one of your React components:
 
         at Boundary.FallbackComponent (<PROJECT_ROOT>/src/__tests__/index.tsx:150:13)
-        at ErrorBoundary (<PROJECT_ROOT>/src/index.tsx:66:3)
+        at ErrorBoundary (<PROJECT_ROOT>/src/index.tsx:72:3)
         at withErrorBoundary(Unknown)
 
     React will try to recreate this component tree from scratch using the error boundary you provided, ErrorBoundary."
@@ -178,7 +178,7 @@ test('withErrorBoundary HOC', () => {
     Object {
       "componentStack": "
         at Boundary.FallbackComponent (<PROJECT_ROOT>/src/__tests__/index.tsx:150:13)
-        at ErrorBoundary (<PROJECT_ROOT>/src/index.tsx:66:3)
+        at ErrorBoundary (<PROJECT_ROOT>/src/index.tsx:72:3)
         at withErrorBoundary(Unknown)",
     }
   `)

src/index.tsx

@@ -16,7 +16,9 @@ interface ErrorBoundaryPropsWithComponent {
   onReset?: (...args: Array<unknown>) => void
   onError?: (error: Error, info: {componentStack: string}) => void
   resetKeys?: Array<unknown>
+  fallback?: never
   FallbackComponent: React.ComponentType<FallbackProps>
+  fallbackRender?: never
 }
 
 declare function FallbackRender(
@@ -34,6 +36,8 @@ interface ErrorBoundaryPropsWithRender {
   onReset?: (...args: Array<unknown>) => void
   onError?: (error: Error, info: {componentStack: string}) => void
   resetKeys?: Array<unknown>
+  fallback?: never
+  FallbackComponent?: never
   fallbackRender: typeof FallbackRender
 }
 
@@ -49,6 +53,8 @@ interface ErrorBoundaryPropsWithFallback {
     unknown,
     string | React.FunctionComponent | typeof React.Component
   > | null
+  FallbackComponent?: never
+  fallbackRender?: never
 }
 
 type ErrorBoundaryProps =
@@ -115,7 +121,7 @@ class ErrorBoundary extends React.Component<
 
   render() {
     const {error} = this.state
-    // @ts-expect-error ts(2339) (at least one of these will be defined though, and we check for their existence)
+
     const {fallbackRender, FallbackComponent, fallback} = this.props
 
     if (error !== null) {
@@ -126,7 +132,7 @@ class ErrorBoundary extends React.Component<
       if (React.isValidElement(fallback)) {
         return fallback
       } else if (typeof fallbackRender === 'function') {
-        return (fallbackRender as typeof FallbackRender)(props)
+        return fallbackRender(props)
       } else if (FallbackComponent) {
         return <FallbackComponent {...props} />
       } else {