test(ngMock window.inject): test extending inject error stack info

Angular's ngMock inject() function, when called outside of a test spec
context will not directly call the provided callback but will instead
return a wrapper function to call the provided function at a later time,
presumably while in some test spec context. And if that is the case,
Angular would like to include the information on the inject() calling
location to be included in the thrown error's stack trace information,
so it manually appends it to the ones included in the actual error's
stack trace.

The added test makes sure this functionality works as expected.

Closes angular#13591

Author: jurko-gospodnetic

test/ngMock/angular-mocksSpec.js

@@ -919,6 +919,23 @@ describe('ngMock', function() {
           });
         }).toThrow('test message');
       }));
+
+      describe('when called outside of test spec context and inject callback throws an Error', function () {
+        function testCaller() {
+          return inject(function () {
+            throw new Error();
+          });
+        }
+        var throwErrorFromInjectCallback = testCaller();
+
+        it('should update thrown Error stack with inject call location', function () {
+          try {
+            throwErrorFromInjectCallback();
+          } catch (e) {
+            expect(e.stack).toMatch('testCaller');
+          }
+        });
+      });
     });
   });