Test for group creation across all `mode` options

[d-v-b]

Based on #2629 it seems that our test suite does not check group creation with mode=w. This probably means a test is not parametrized completely. This should be fixed.

[dikwickley]

@d-v-b added a pr for this.

[AdityaChaubeyIITM]

Hi, is this issue fixed? If not, I would like to work on it

[asimchoudhary]

Hii @d-v-b , i have opened the pr #2840 for the above issue.