Fix merge when object is undefined

[lucianodltec]

Please check changes in merge.ts. That allows restoring initial null object from storage.

[codecov]

Codecov Report

Merging #40 (2b44bb7) into master (57721d9) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##            master       #40   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            6         6           
  Lines           98        99    +1     
  Branches        13        14    +1     
=========================================
+ Hits            98        99    +1     

Impacted Files	Coverage Δ
src/merge.ts	100.00% <100.00%> (ø)

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[maple3142]

Could you add a test case about this change?

[lucianodltec]

Hi mapple3142.

In my app, I have vuex namespaced two modules. On system module, it does have a state called "auth" which is an object like the below:

auth = { token: '.....hold jwt token...', access: { 'GET/system/user': true, 'GET/system/role: true }, user: { id: 'some-guid', name: 'xxxx', } }

So, configure vuejs-storage to persist "system.auth" state. It writes OK on localStorage, but when I try to reload app it's raising an exception that could not use operator "in" to retrieve "user". I guess the "merge" code I propposed creates an empty "user" object so it can interacts creating user attrs id and name.

Hope this helps to understand. If not I'll try to give you an sample app.

Thanks for your attention.

[atilacamurca]

I had similar problems with attributes containing null values