Throw more specific error, ArgumentError, rather than a general Error()

[petershintech]

Also changed the unit test to check ArgumentError, not ErrorException.
#1867

[petershintech]

@bkamins Thanks. I agree your code is easy to read. In fact, I can see several long lines exploiting short circuits. Do you think we need to rewrite the lines to more readable ones? If so, I can help you.

[bkamins]

I can see several long lines exploiting short circuits.

Sure - thank you. The "soft" rule is that lines should not be longer than 92 characters.

[petershintech]

I like the new message about more specific about the cause. Commit to the branch and ready to be merged. Thanks.

[petershintech]

One quick question before merging. In this case,
if !(size(df, 1) == length(item) || size(df, 2) == 0)
should I throw ArgumentError or DimensionMismatch? I think the latter one is more specific about error cause so it would be better than the first one. What do you think of it?

[nalimilan]

Right, DimensionMismatch sounds better.

[petershintech]

Ok. I have replaced ArgumentError with DimensionMismatch and also touched a unit test for it. I can see the same change would be desirable for some other code lines but it can be captured in a separate PR. I think it is ready to merge. Thanks for all your inputs.

[bkamins]

Yes, we used ArgumentError or BoundsError only everywhere up till now. We can be more specific of course 😄. Thank you.