Fix assertion helper function

Author: bvaughn

src/assertErrorBoundaryContext.ts

@@ -2,14 +2,12 @@ import { ErrorBoundaryContextType } from "./ErrorBoundaryContext";
 
 export function assertErrorBoundaryContext(
   value: any
-): value is ErrorBoundaryContextType {
+): asserts value is ErrorBoundaryContextType {
   if (
     value == null ||
     typeof value.didCatch !== "boolean" ||
     typeof value.resetErrorBoundary !== "function"
   ) {
     throw new Error("ErrorBoundaryContext not found");
   }
-
-  return true;
 }

src/useErrorBoundary.ts

@@ -24,7 +24,7 @@ export function useErrorBoundary<TError = any>(): UseErrorBoundaryApi<TError> {
   const memoized = useMemo(
     () => ({
       resetBoundary: () => {
-        context?.resetErrorBoundary();
+        context.resetErrorBoundary();
         setState({ error: null, hasError: false });
       },
       showBoundary: (error: TError) =>
@@ -33,7 +33,7 @@ export function useErrorBoundary<TError = any>(): UseErrorBoundaryApi<TError> {
           hasError: true,
         }),
     }),
-    [context?.resetErrorBoundary]
+    [context.resetErrorBoundary]
   );
 
   if (state.hasError) {