add more unittests

4 jobs for CI in 5 minutes and 44 seconds (queued for 1 second)
Status Job ID Name Coverage
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passed #79661
Linux
clang-c++11

00:05:43

passed #79663
Linux
clang-c++14

00:05:43

passed #79660
Linux
gcc-c++11

00:01:08

passed #79662
Linux
gcc-c++14

00:01:35