"Basil L. Contovounesios" <contovob@tcd.ie> writes:

> "Basil L. Contovounesios" <contovob@tcd.ie> writes:
>
>> diff --git a/lisp/button.el b/lisp/button.el
>> index 9112e518b0..ae2488bac6 100644
>> --- a/lisp/button.el
>> +++ b/lisp/button.el
>> @@ -470,13 +470,22 @@ push-button
>>  	(button-activate button use-mouse-action)
>>  	t))))
>>  
>> +(defun button--help-echo (button)
>> +  "Evaluate BUTTON's `help-echo' property and return its value."
>> +  (let ((help (button-get button 'help-echo)))
>> +    (if (functionp help)
>> +        (let ((obj (if (overlayp button) button (current-buffer))))
>> +          (funcall help (selected-window) obj (button-start button)))
>> +      (eval help lexical-binding))))
>
> Note that I intend to enable lexical-binding in button.el in a future
> patch, in which case this call to eval will not need changing.

Er, I was confused when I wrote this - whether button.el uses
lexical-binding is irrelevant to the lexical evaluation of forms.

The following is an updated patch which tests form evaluation under both
dynamic and lexical scoping.  I still intend to push it soon, if there
are no objections.