[FLINK-15266] Fix NPE for case operator code gen in blink planner#10594

Merged

wuchong merged 4 commits intoapache:masterfrom libenchao:bugfix/fix_npe_for_case_when_in_blink

Dec 20, 2019

+10-3

Commits on Dec 16, 2019

[FLINK-15266] Fix NPE for case operator code gen in blink planner
libenchao
committed

Commits on Dec 19, 2019

add tests, and check null before assignment
libenchao
committed

Commits on Dec 20, 2019