Skip computation incase of Null Literal for case/when transformation

[abhioncbr]

As per the discussion of the PR

• Skipping computation of value block in case of Null Literal for case/when transformation.

cc @shenyu0127 @Jackie-Jiang

[codecov-commenter]

Codecov Report

Merging #11444 (b876be1) into master (2b40362) will increase coverage by 0.02%.
Report is 2 commits behind head on master.
The diff coverage is 83.33%.

@@             Coverage Diff              @@
##             master   #11444      +/-   ##
============================================
+ Coverage     62.99%   63.02%   +0.02%     
+ Complexity     1107     1095      -12     
============================================
  Files          2303     2302       -1     
  Lines        124041   124032       -9     
  Branches      18895    18901       +6     
============================================
+ Hits          78137    78168      +31     
+ Misses        40352    40320      -32     
+ Partials       5552     5544       -8     

Flag	Coverage Δ
integration	<0.01% <0.00%> (ø)
integration1	<0.01% <0.00%> (ø)
integration2	0.00% <0.00%> (ø)
java-11	62.99% <83.33%> (+0.02%)	⬆️
java-17	62.85% <83.33%> (+<0.01%)	⬆️
java-20	62.86% <83.33%> (+0.01%)	⬆️
temurin	63.02% <83.33%> (+0.02%)	⬆️
unittests	63.01% <83.33%> (+0.02%)	⬆️
unittests1	67.56% <83.33%> (+0.03%)	⬆️
unittests2	14.47% <0.00%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files Changed	Coverage Δ
...ator/transform/function/CaseTransformFunction.java	57.32% <81.81%> (+1.74%)	⬆️
...r/transform/function/LiteralTransformFunction.java	74.19% <100.00%> (-0.81%)	⬇️

... and 28 files with indirect coverage changes

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[Jackie-Jiang]

LGTM otherwise

[shenyu0127]

If would be good to add a test to CaseTransformFunctionTest which uses a query "SELECT CASE WHEN xx THEN xx ELSE NULL" and assert the query results to exercise the modified code paths.

[shenyu0127]

If would be good to add a test to CaseTransformFunctionTest which uses a query "SELECT CASE WHEN xx THEN xx ELSE NULL" and assert the query results to exercise the modified code paths.

Did you add a test? The rest looks good to me.