please flow gods

jestjs · Apr 16, 2018 · 7e87a84 · 7e87a84
1 parent d01429f
commit 7e87a84
Showing 1 changed file with 11 additions and 4 deletions.
diff --git a/packages/jest-jasmine2/src/expectation_result_factory.js b/packages/jest-jasmine2/src/expectation_result_factory.js
@@ -31,16 +31,20 @@ function messageFormatter({error, message, passed}) {
   return `thrown: ${prettyFormat(error, {maxDepth: 3})}`;
 }
 
-function stackFormatter(options, initError, errorMessage) {
+function stackFormatter(options, initError?, errorMessage) {
   if (options.passed) {
     return '';
   }
 
-  if ((options.error && options.error.stack)) {
+  if (options.error && options.error.stack) {
     return options.error.stack;
   }
 
-  return errorMessage + '\n' + initError.stack;
+  if (initError) {
+    return errorMessage + '\n' + initError.stack;
+  }
+
+  return new Error(errorMessage).stack;
 }
 
 type Options = {
@@ -52,7 +56,10 @@ type Options = {
   message?: string,
 };
 
-export default function expectationResultFactory(options: Options, initError) {
+export default function expectationResultFactory(
+  options: Options,
+  initError?: Error,
+) {
   const message = messageFormatter(options);
   const stack = stackFormatter(options, initError, message);