(function-documentation): Make it work for the remaining cases

* lisp/simple.el (function-documentation):
Use `internal-subr-documentation` and make it work also with symbols
and macros.

* src/doc.c (Fsubr_documentation): New function, extracted
from Fdocumentation.
(syms_of_doc): defsubr it.
(Fdocumentation): Don't handle subrs and module functions here.

1 files changed, 21 insertions, 13 deletions

diff --git a/src/doc.c b/src/doc.c
index df57f84603e..174341523d7 100644
--- a/src/doc.c
+++ b/src/doc.c
@@ -330,19 +330,7 @@ string is passed through `substitute-command-keys'.  */)
     xsignal1 (Qvoid_function, function);
   if (CONSP (fun) && EQ (XCAR (fun), Qmacro))
     fun = XCDR (fun);
-#ifdef HAVE_NATIVE_COMP
-  if (!NILP (Fsubr_native_elisp_p (fun)))
-    doc = native_function_doc (fun);
-  else
-#endif
-  if (SUBRP (fun))
-    doc = make_fixnum (XSUBR (fun)->doc);
-#ifdef HAVE_MODULES
-  else if (MODULE_FUNCTIONP (fun))
-    doc = module_function_documentation (XMODULE_FUNCTION (fun));
-#endif
-  else
-    doc = call1 (Qfunction_documentation, fun);
+  doc = call1 (Qfunction_documentation, fun);
 
   /* If DOC is 0, it's typically because of a dumped file missing
      from the DOC file (bug in src/Makefile.in).  */
@@ -371,6 +359,25 @@ string is passed through `substitute-command-keys'.  */)
   return doc;
 }
 
+DEFUN ("internal-subr-documentation", Fsubr_documentation, Ssubr_documentation, 1, 1, 0,
+       doc: /* Return the raw documentation info of a C primitive.  */)
+  (Lisp_Object function)
+{
+#ifdef HAVE_NATIVE_COMP
+  if (!NILP (Fsubr_native_elisp_p (function)))
+    return native_function_doc (function);
+  else
+#endif
+  if (SUBRP (function))
+    return make_fixnum (XSUBR (function)->doc);
+#ifdef HAVE_MODULES
+  else if (MODULE_FUNCTIONP (function))
+    return module_function_documentation (XMODULE_FUNCTION (function));
+#endif
+  else
+    return Qt;
+}
+
 DEFUN ("documentation-property", Fdocumentation_property,
        Sdocumentation_property, 2, 3, 0,
        doc: /* Return the documentation string that is SYMBOL's PROP property.
@@ -713,6 +720,7 @@ compute the correct value for the current terminal in the nil case.  */);
   /* Initialized by ‘main’.  */
 
   defsubr (&Sdocumentation);
+  defsubr (&Ssubr_documentation);
   defsubr (&Sdocumentation_property);
   defsubr (&Ssnarf_documentation);
   defsubr (&Stext_quoting_style);