Fix for ArrayIndexOutOfBoundsException in #371

[petertrr]

What's done:

• Changed logic
• Added tests

This pull request closes #371

[codecov]

Codecov Report

Merging #612 (17dc903) into master (ac92d54) will increase coverage by 0.01%.
The diff coverage is 86.36%.

@@             Coverage Diff              @@
##             master     #612      +/-   ##
============================================
+ Coverage     80.73%   80.75%   +0.01%     
+ Complexity     1746     1745       -1     
============================================
  Files            89       89              
  Lines          4614     4613       -1     
  Branches       1386     1385       -1     
============================================
  Hits           3725     3725              
  Misses          322      322              
+ Partials        567      566       -1     

Flag	Coverage Δ	Complexity Δ
unittests	80.75% <86.36%> (+0.01%)	0.00 <4.00> (ø)

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Impacted Files	Coverage Δ	Complexity Δ
...tlin/org/cqfn/diktat/ruleset/utils/AstNodeUtils.kt	84.82% <72.72%> (+0.82%)	0.00 <0.00> (ø)
...at/ruleset/rules/identifiers/LocalVariablesRule.kt	92.42% <100.00%> (ø)	24.00 <4.00> (ø)
...fn/diktat/ruleset/rules/classes/DataClassesRule.kt	83.33% <0.00%> (-2.39%)	25.00% <0.00%> (-1.00%)

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[orchestr7]

Why it should return nullable??

[petertrr]

You're right, I use non-null assert on every call. I'll check and throw error here and return non-nullable value.

[orchestr7]

lgtm