Current implementation of @stamp/core/mergeOne() does not fully check if its first parameter dst is undefined. If the second parameter src is an object, dst is never checked and assumed to be an array/object and thus a TypeError: Cannot read property 'foo' of undefined is thrown.
stamp/packages/collision/index.js line 33
This issue is triggered by unit tests and standardiseDescriptor() (in packages/it/index.js lines:41, 47 and 56
This issue relates with #52