bug#20333: 24.3; Add warning about shell quoting to documentation of combine-and-quote-strings

bug#20333: 24.3; Add warning about shell quoting to documentation of combine-and-quote-strings

[Philipp Stephani]

Context and more discussion:
http://lists.gnu.org/archive/html/help-gnu-emacs/2015-04/msg00179.html

It would be great if the documentation string and the Elisp manual about
`combine-and-quote-strings' could be made a bit clearer by explicitly
stating that this function is not useful for shell quoting.


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bug#20333: 24.3; Add warning about shell quoting to documentation of combine-and-quote-strings

[npostavs]

[-- Attachment #1: Type: text/plain, Size: 406 bytes --]

tags 20333 patch
quit

Philipp Stephani <p.stephani2@gmail.com> writes:

> Context and more discussion:
> http://lists.gnu.org/archive/html/help-gnu-emacs/2015-04/msg00179.html
>
> It would be great if the documentation string and the Elisp manual about
> `combine-and-quote-strings' could be made a bit clearer by explicitly
> stating that this function is not useful for shell quoting.

How about this:


[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: patch --]
[-- Type: text/x-diff, Size: 2037 bytes --]

From 5a1d23231bcf3c279fd3b09654fb132513748e6c Mon Sep 17 00:00:00 2001
From: Noam Postavsky <npostavs@gmail.com>
Date: Sun, 3 Jul 2016 09:56:36 -0400
Subject: [PATCH v1] Note combine-and-quote-strings doesn't shell quote

* doc/lispref/processes.texi (Shell Arguments):
* lisp/subr.el (combine-and-quote-strings): Add a note that
combine-and-quote-strings doesn't protect arguments against shell
evaluation (Bug #20333).
---
 doc/lispref/processes.texi | 5 +++++
 lisp/subr.el               | 5 ++++-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/doc/lispref/processes.texi b/doc/lispref/processes.texi
index 5bd0b11..b4542f6 100644
--- a/doc/lispref/processes.texi
+++ b/doc/lispref/processes.texi
@@ -215,6 +215,11 @@ Shell Arguments
 string arguments to be passed to @code{call-process} or
 @code{start-process}, or for converting such lists of arguments into
 a single Lisp string to be presented in the minibuffer or echo area.
+Note that if a shell is involved (e.g., if using
+@code{call-process-shell-command}), arguments should still be
+protected by @code{shell-quote-argument};
+@code{combine-and-quote-strings} is @emph{not} intended to protect
+special characters from shell evaluation.
 
 @defun split-string-and-unquote string &optional separators
 This function splits @var{string} into substrings at matches for the
diff --git a/lisp/subr.el b/lisp/subr.el
index ed2166a..e9e19d3 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -3706,7 +3706,10 @@ combine-and-quote-strings
   "Concatenate the STRINGS, adding the SEPARATOR (default \" \").
 This tries to quote the strings to avoid ambiguity such that
   (split-string-and-unquote (combine-and-quote-strings strs)) == strs
-Only some SEPARATORs will work properly."
+Only some SEPARATORs will work properly.
+
+Note that this is not intended to protect STRINGS from
+interpretation by shells, use `shell-quote-argument' for that."
   (let* ((sep (or separator " "))
          (re (concat "[\\\"]" "\\|" (regexp-quote sep))))
     (mapconcat
-- 
2.8.0

bug#20333: 24.3; Add warning about shell quoting to documentation of combine-and-quote-strings

[Philipp Stephani]

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<npostavs@users.sourceforge.net> schrieb am So., 3. Juli 2016 um 16:03 Uhr:

> tags 20333 patch
> quit
>
> Philipp Stephani <p.stephani2@gmail.com> writes:
>
> > Context and more discussion:
> > http://lists.gnu.org/archive/html/help-gnu-emacs/2015-04/msg00179.html
> >
> > It would be great if the documentation string and the Elisp manual about
> > `combine-and-quote-strings' could be made a bit clearer by explicitly
> > stating that this function is not useful for shell quoting.
>
> How about this:
>
>
Looks good, thanks.

[-- Attachment #2: Type: text/html, Size: 1062 bytes --]

bug#20333: 24.3; Add warning about shell quoting to documentation of combine-and-quote-strings

[Eli Zaretskii]

> From: npostavs@users.sourceforge.net
> Date: Sun, 03 Jul 2016 10:03:55 -0400
> Cc: 20333@debbugs.gnu.org
> 
> >From 5a1d23231bcf3c279fd3b09654fb132513748e6c Mon Sep 17 00:00:00 2001
> From: Noam Postavsky <npostavs@gmail.com>
> Date: Sun, 3 Jul 2016 09:56:36 -0400
> Subject: [PATCH v1] Note combine-and-quote-strings doesn't shell quote
> 
> * doc/lispref/processes.texi (Shell Arguments):
> * lisp/subr.el (combine-and-quote-strings): Add a note that
> combine-and-quote-strings doesn't protect arguments against shell
> evaluation (Bug #20333).
> ---
>  doc/lispref/processes.texi | 5 +++++
>  lisp/subr.el               | 5 ++++-
>  2 files changed, 9 insertions(+), 1 deletion(-)
> 
> diff --git a/doc/lispref/processes.texi b/doc/lispref/processes.texi
> index 5bd0b11..b4542f6 100644
> --- a/doc/lispref/processes.texi
> +++ b/doc/lispref/processes.texi
> @@ -215,6 +215,11 @@ Shell Arguments
>  string arguments to be passed to @code{call-process} or
>  @code{start-process}, or for converting such lists of arguments into
>  a single Lisp string to be presented in the minibuffer or echo area.
> +Note that if a shell is involved (e.g., if using
> +@code{call-process-shell-command}), arguments should still be
> +protected by @code{shell-quote-argument};
> +@code{combine-and-quote-strings} is @emph{not} intended to protect
> +special characters from shell evaluation.
>  
>  @defun split-string-and-unquote string &optional separators
>  This function splits @var{string} into substrings at matches for the
> diff --git a/lisp/subr.el b/lisp/subr.el
> index ed2166a..e9e19d3 100644
> --- a/lisp/subr.el
> +++ b/lisp/subr.el
> @@ -3706,7 +3706,10 @@ combine-and-quote-strings
>    "Concatenate the STRINGS, adding the SEPARATOR (default \" \").
>  This tries to quote the strings to avoid ambiguity such that
>    (split-string-and-unquote (combine-and-quote-strings strs)) == strs
> -Only some SEPARATORs will work properly."
> +Only some SEPARATORs will work properly.
> +
> +Note that this is not intended to protect STRINGS from
> +interpretation by shells, use `shell-quote-argument' for that."
>    (let* ((sep (or separator " "))
>           (re (concat "[\\\"]" "\\|" (regexp-quote sep))))
>      (mapconcat
> -- 
> 2.8.0

LGTM, thanks.  This is good for emacs-25.

bug#20333: 24.3; Add warning about shell quoting to documentation of combine-and-quote-strings

[npostavs]

tags 20333 fixed
close 20333 25.1
quit

Eli Zaretskii <eliz@gnu.org> writes:
>
> LGTM, thanks.  This is good for emacs-25.

Pushed as 178b2f59