Raise test coverage

[Sakhnovkrg]

Q	A
Is bugfix?	❌
New feature?	✔️
Breaks BC?	❌

Related to #233

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 88.42%. Comparing base (5f6c889) to head (f912842). Report is 1 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff              @@
##             master     #279      +/-   ##
============================================
+ Coverage     86.17%   88.42%   +2.24%     
  Complexity      642      642              
============================================
  Files            50       50              
  Lines          2185     2185              
============================================
+ Hits           1883     1932      +49     
+ Misses          302      253      -49     

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[vjik]

@Sakhnovkrg It is not necessary to use force push. Many commits in PR is OK, we are squash them on merge.

[samdark]

Thank you! We'll continue adding more tests.