bug#65852: 30.0.50; image-auto-resize :type has choices in wrong order

[Mattias Engdegård]

I now see that we have an existing defcustom check that runs very late in the 
compilation.
Although I prefer this kind of check to be carried out during macro-expansion, 
doing so has the disadvantage that actual values aren't always available. On 
the other hand, defcustom arguments are usually constants.

Anyway, I went overboard and wrote a sizeable expansion to the current set of 
warnings and now also checks :type args in define-widget (see attached patch). 
Try it out and tell me what you think. Maybe the regexp check is too ad-hocky.

Another warning that I rather like but may give too many false positives is 
that of `const` and `other` types without an actual value which is then assumed 
to be nil. This seems to be an undocumented 'feature' but it doesn't help 
readability; it's often unclear whether `nil` was intended or just a result of 
a forgotten value.

more-defcustom-warnings.diff
Description: Binary data