Commit 6f3ff47c authored by Juanma Barranquero's avatar Juanma Barranquero

Make help-split-fundoc more flexible about what returns

* lisp/help.el (help-split-fundoc): New arg SECTION to return
only the usage or doc parts of the docstring, or both even if
there is no usage.

* test/lisp/help-tests.el: New file.
parent 4b5d04be
......@@ -1380,27 +1380,39 @@ The result, when formatted by `substitute-command-keys', should equal STRING."
;; But for various reasons, they are more widely needed, so they were
;; moved to this file, which is preloaded. https://debbugs.gnu.org/17001
(defun help-split-fundoc (docstring def)
(defun help-split-fundoc (docstring def &optional section)
"Split a function DOCSTRING into the actual doc and the usage info.
Return (USAGE . DOC) or nil if there's no usage info, where USAGE info
is a string describing the argument list of DEF, such as
\"(apply FUNCTION &rest ARGUMENTS)\".
DEF is the function whose usage we're looking for in DOCSTRING."
Return (USAGE . DOC), where USAGE is a string describing the argument
list of DEF, such as \"(apply FUNCTION &rest ARGUMENTS)\".
DEF is the function whose usage we're looking for in DOCSTRING.
With SECTION nil, return nil if there is no usage info; conversely,
SECTION t means to return (USAGE . DOC) even if there's no usage info.
When SECTION is \\='usage or \\='doc, return only that part."
;; Functions can get the calling sequence at the end of the doc string.
;; In cases where `function' has been fset to a subr we can't search for
;; function's name in the doc string so we use `fn' as the anonymous
;; function name instead.
(when (and docstring (string-match "\n\n(fn\\(\\( .*\\)?)\\)\\'" docstring))
(let ((doc (unless (zerop (match-beginning 0))
(substring docstring 0 (match-beginning 0))))
(usage-tail (match-string 1 docstring)))
(cons (format "(%s%s"
;; Replace `fn' with the actual function name.
(if (symbolp def)
(help--docstring-quote (format "%S" def))
'anonymous)
usage-tail)
doc))))
(let* ((found (and docstring
(string-match "\n\n(fn\\(\\( .*\\)?)\\)\\'" docstring)))
(doc (if found
(and (memq section '(t nil doc))
(not (zerop (match-beginning 0)))
(substring docstring 0 (match-beginning 0)))
docstring))
(usage (and found
(memq section '(t nil usage))
(let ((tail (match-string 1 docstring)))
(format "(%s%s"
;; Replace `fn' with the actual function name.
(if (and (symbolp def) def)
(help--docstring-quote (format "%S" def))
'anonymous)
tail)))))
(pcase section
(`nil (and usage (cons usage doc)))
(`t (cons usage doc))
(`usage usage)
(`doc doc))))
(defun help-add-fundoc-usage (docstring arglist)
"Add the usage info to DOCSTRING.
......
;;; help-tests.el --- Tests for help.el -*- lexical-binding: t; -*-
;; Copyright (C) 2019 Free Software Foundation, Inc.
;; Author: Juanma Barranquero <lekktu@gmail.com>
;; Keywords: help, internal
;; This file is part of GNU Emacs.
;; GNU Emacs is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.
;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;; GNU General Public License for more details.
;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs. If not, see <https://www.gnu.org/licenses/>.
;;; Code:
(require 'ert)
(ert-deftest help-split-fundoc-SECTION ()
"Test new optional arg SECTION."
(let* ((doc "Doc first line.\nDoc second line.")
(usg "\n\n(fn ARG1 &optional ARG2)")
(full (concat doc usg))
(usage "(t ARG1 &optional ARG2)"))
;; Docstring has both usage and doc
(should (equal (help-split-fundoc full t nil) `(,usage . ,doc)))
(should (equal (help-split-fundoc full t t) `(,usage . ,doc)))
(should (equal (help-split-fundoc full t 'usage) usage))
(should (equal (help-split-fundoc full t 'doc) doc))
;; Docstring has no usage, only doc
(should (equal (help-split-fundoc doc t nil) nil))
(should (equal (help-split-fundoc doc t t) `(nil . ,doc)))
(should (equal (help-split-fundoc doc t 'usage) nil))
(should (equal (help-split-fundoc doc t 'doc) doc))
;; Docstring is only usage, no doc
(should (equal (help-split-fundoc usg t nil) `(,usage . nil)))
(should (equal (help-split-fundoc usg t t) `(,usage . nil)))
(should (equal (help-split-fundoc usg t 'usage) usage))
(should (equal (help-split-fundoc usg t 'doc) nil))
;; Docstring is null
(should (equal (help-split-fundoc nil t nil) nil))
(should (equal (help-split-fundoc nil t t) '(nil)))
(should (equal (help-split-fundoc nil t 'usage) nil))
(should (equal (help-split-fundoc nil t 'doc) nil))))
(provide 'help-tests)
;;; help-tests.el ends here
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment