[Enhancement] Cover more unit test for s1, s2 and mspie

[LeoXing1996]

No description provided.

[codecov]

Codecov Report

Merging #237 (ae82285) into master (40376b4) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #237   +/-   ##
=======================================
  Coverage   76.75%   76.75%           
=======================================
  Files         130      130           
  Lines        9421     9421           
  Branches     1899     1899           
=======================================
  Hits         7231     7231           
  Misses       1726     1726           
  Partials      464      464           

Flag	Coverage Δ
unittests	76.75% <ø> (ø)

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