a property "definition-type" would help find macro-defined tests

a property "definition-type" would help find macro-defined tests

[Stephen Gildea]

The find-function feature of Emacs cannot find "ert-deftest"
forms generated by a macro.  (The find-func library does look
through macro expansions in its search, but the search is too
specific to find "ert-deftest" forms.)

Function "find-function-search-for-symbol" is passed a "type"
for the thing to look for, but that type is based on the
caller's idea of what the thing is.  We need a way to say what
the definer thinks the definition looks like.

The existing property "definition-name" isn't helpful here
because often the call to a test-defining macro contains test
data only.

I propose a new property, "definition-type", that a macro could
put on a symbol.  If present, "find-function-search-for-symbol"
would use that type instead of the passed-in type.

With this enhancement, any subsystem that uses a macro to
define objects could
 - have the macro set property "definition-type" on the
   symbols it defines, and
 - add an entry to "find-function-regexp-alist" saying how to
   find the new type.

Concretely, here's the code change I'm proposing:

diff --git a/lisp/emacs-lisp/find-func.el b/lisp/emacs-lisp/find-func.el
index f3ddf9f81c9..df1eb8deae0 100644
--- a/lisp/emacs-lisp/find-func.el
+++ b/lisp/emacs-lisp/find-func.el
@@ -409,6 +409,8 @@ find-function-search-for-symbol
   ;; Some functions are defined as part of the construct
   ;; that defines something else.
   (while (and (symbolp symbol) (get symbol 'definition-name))
     (setq symbol (get symbol 'definition-name)))
+  (setq type (or (get symbol 'definition-type)
+                 type))
   (if (string-match "\\`src/\\(.*\\.\\(c\\|m\\)\\)\\'" library)
       (find-function-C-source symbol (match-string 1 library) type)


Does this seem like a generally useful addition?

 < Stephen

Re: a property "definition-type" would help find macro-defined tests

[Richard Lawrence]

Stephen Gildea <stepheng+emacs@gildea.com> writes:

> I propose a new property, "definition-type", that a macro could
> put on a symbol.  If present, "find-function-search-for-symbol"
> would use that type instead of the passed-in type.
>
> With this enhancement, any subsystem that uses a macro to
> define objects could
>  - have the macro set property "definition-type" on the
>    symbols it defines, and
>  - add an entry to "find-function-regexp-alist" saying how to
>    find the new type.
> ...
> Does this seem like a generally useful addition?

As someone who's recently written a macro to define a bunch of tests,
and was then mildly frustrated that e.g.
ert-results-pop-to-should-forms-for-test-at-point didn't even come close
to finding the definitions, something like this sounds useful to me!

I wonder if there isn't already some better way to do this, though, that
find-function-search-for-symbol could make use of. I got curious and
briefly went down a rabbit hole looking for one, since there are
functions like `symbol-file' and the intriguing `symbol-with-pos-pos'.
The latter extracts a position from a mysterious-to-me entity called a
"symbol with position". Perhaps there's *already* a standard way to tag
a symbol with a position in a source file somehow, and what's needed is
to encourage macro writers to use it, and to adjust the find-function*
functions to look for it? Someone who knows more than me about Emacs
internals could shed more light here...but anyway, if there isn't, I
like the idea!

Best,
Richard