bug#563: `find-func.el': interactive-form of `find-library' fails

bug#563: `find-func.el': interactive-form of `find-library' fails

[Richard Copley]

To reproduce,
   Visit a library file containing a `require' form, e.g.,
   "M-x find-library RET yow RET". Search for a `require' form and
   position point on its the opening left parenthesis.  Invoke
   `find-library' interactively with "M-x find-library RET".

Symptom
   Instead of prompting for a library name, Emacs displays the error message
   `Scan error: "Unbalanced parentheses", 1222, 1'.

Problem
   The error is in the interactive form of `find-library' in `find-func.el'.
   If point is over the opening left-paren of the `require' form then
   `function-called-at-point' returns `require', whereupon `backward-up-list'
   fails because point is not in a list.

Suggestions (for what they're worth :)
   (a) Handle this special case in the `find-library' interactive form.
   (b) Modify `function-called-at-point' to do what its docstring says.
   (c) In the `find-function' interactive form, use `condtition-case'
       to detect errors in computing the default.



In GNU Emacs 22.2.1 (i386-mingw-nt6.0.6001)
 of 2008-03-26 on RELEASE
Windowing system distributor `Microsoft Corp.', version 6.0.6001
configured using `configure --with-gcc (3.4)'

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: ENG
  locale-coding-system: cp1252
  default-enable-multibyte-characters: t

Major mode: Fundamental

Minor modes in effect:
  show-paren-mode: t
  encoded-kbd-mode: t
  tooltip-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  blink-cursor-mode: t
  unify-8859-on-encoding-mode: t
  utf-translate-cjk-mode: t
  auto-compression-mode: t
  line-number-mode: t

bug#563: marked as done (`find-func.el': interactive-form of `find-library' fails)

[Emacs bug Tracking System]

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Your message dated Tue, 12 Aug 2008 23:08:37 -0400
with message-id <5d4p5pipca.fsf@fencepost.gnu.org>
and subject line Re: bug#563: `find-func.el': interactive-form of `find-library' fails
has caused the Emacs bug report #563,
regarding `find-func.el': interactive-form of `find-library' fails
to be marked as done.

This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
bug report if necessary, and/or fix the problem forthwith.

(NB: If you are a system administrator and have no idea what this
message is talking about, this may indicate a serious mail system
misconfiguration somewhere. Please contact don@donarmstrong.com
immediately.)


-- 
563: http://emacsbugs.donarmstrong.com/cgi-bin/bugreport.cgi?bug=563
Emacs Bug Tracking System
Contact don@donarmstrong.com with problems

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From: "Richard Copley" <rcopley@gmail.com>
To: "bug-gnu-emacs@gnu.org" <bug-gnu-emacs@gnu.org>
Subject: `find-func.el': interactive-form of `find-library' fails
Date: Tue, 15 Jul 2008 15:46:55 +0100
Message-ID: <afe5197f0807150746w2baf5658hffc559be1be4a857@mail.gmail.com>

To reproduce,
   Visit a library file containing a `require' form, e.g.,
   "M-x find-library RET yow RET". Search for a `require' form and
   position point on its the opening left parenthesis.  Invoke
   `find-library' interactively with "M-x find-library RET".

Symptom
   Instead of prompting for a library name, Emacs displays the error message
   `Scan error: "Unbalanced parentheses", 1222, 1'.

Problem
   The error is in the interactive form of `find-library' in `find-func.el'.
   If point is over the opening left-paren of the `require' form then
   `function-called-at-point' returns `require', whereupon `backward-up-list'
   fails because point is not in a list.

Suggestions (for what they're worth :)
   (a) Handle this special case in the `find-library' interactive form.
   (b) Modify `function-called-at-point' to do what its docstring says.
   (c) In the `find-function' interactive form, use `condtition-case'
       to detect errors in computing the default.



In GNU Emacs 22.2.1 (i386-mingw-nt6.0.6001)
 of 2008-03-26 on RELEASE
Windowing system distributor `Microsoft Corp.', version 6.0.6001
configured using `configure --with-gcc (3.4)'

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: ENG
  locale-coding-system: cp1252
  default-enable-multibyte-characters: t

Major mode: Fundamental

Minor modes in effect:
  show-paren-mode: t
  encoded-kbd-mode: t
  tooltip-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  blink-cursor-mode: t
  unify-8859-on-encoding-mode: t
  utf-translate-cjk-mode: t
  auto-compression-mode: t
  line-number-mode: t




[-- Attachment #3: Type: message/rfc822, Size: 1842 bytes --]

From: Glenn Morris <rgm@gnu.org>
To: Richard Copley <rcopley@gmail.com>
Cc: 563-done@emacsbugs.donarmstrong.com
Subject: Re: bug#563: `find-func.el': interactive-form of `find-library' fails
Date: Tue, 12 Aug 2008 23:08:37 -0400
Message-ID: <5d4p5pipca.fsf@fencepost.gnu.org>


Fix sync'd from trunk to 22, bug closed.

2008-08-13  Martin Rudalics  <rudalics@gmx.at>

            * emacs-lisp/find-func.el (find-library): Wrap search for
            library name in condition-case to avoid reporting a scan-error.
            (Bug#563)  (sync from trunk 2008-01-25)