Add catchOnly to ApplicativeError.

[takayahilton]

No description provided.

[codecov-io]

Codecov Report

Merging #3165 into master will decrease coverage by 0.04%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #3165      +/-   ##
==========================================
- Coverage   93.04%   92.99%   -0.05%     
==========================================
  Files         376      376              
  Lines        7374     7381       +7     
  Branches      209      195      -14     
==========================================
+ Hits         6861     6864       +3     
- Misses        513      517       +4

Flag	Coverage Δ
#scala_version_212	93.32% <100%> (-0.03%)	⬇️
#scala_version_213	90.59% <100%> (-0.05%)	⬇️

Impacted Files	Coverage Δ
core/src/main/scala/cats/instances/try.scala	96.72% <100%> (+0.11%)	⬆️
core/src/main/scala/cats/ApplicativeError.scala	86.2% <100%> (-13.8%)	⬇️
core/src/main/scala/cats/data/Kleisli.scala	90.82% <0%> (-0.09%)	⬇️
...n/scala/cats/kernel/instances/QueueInstances.scala	100% <0%> (ø)	⬆️
...in/scala/cats/kernel/instances/ListInstances.scala	100% <0%> (ø)	⬆️
core/src/main/scala/cats/data/Validated.scala	100% <0%> (ø)	⬆️
.../scala/cats/kernel/instances/VectorInstances.scala	100% <0%> (ø)	⬆️
core/src/main/scala/cats/MonadError.scala	100% <0%> (ø)	⬆️
.../scala/cats/kernel/instances/OptionInstances.scala	100% <0%> (ø)	⬆️

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[travisbrown]

Looks reasonable to me.

[rossabaker]

Might it be useful to also test that catchOnly on an unrelated exception does not catch?

[satorg]

Out of curiosity... I'm struggling to understand this.

What was the T >: Null constraint added for in there? To me it seems that due to the latter constraint T <: Throwable the former one will be always satisfied automatically, won't it? This is because Throwable is AnyRef and Null <: T <: AnyRef for any T.

Or am I missing something?
@takayahilton could you clarify please?