[latex3-commits] [git/LaTeX3-latex3-latex3] master: Update \sys_shell_get:nnN return value (see #538) (01e5777)

[Joseph Wright]

Repository : https://github.com/latex3/latex3
On branch  : master
Link       : https://github.com/latex3/latex3/commit/01e57777ff6c512f60964fb1eb57dabb0c1b9da4

>---------------------------------------------------------------

commit 01e57777ff6c512f60964fb1eb57dabb0c1b9da4
Author: Joseph Wright <joseph.wright at morningstar2.co.uk>
Date:   Sat Feb 16 09:44:17 2019 +0000

    Update \sys_shell_get:nnN return value (see #538)


>---------------------------------------------------------------

01e57777ff6c512f60964fb1eb57dabb0c1b9da4
 l3kernel/CHANGELOG.md     |    4 ++++
 l3kernel/l3candidates.dtx |    7 ++++---
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/l3kernel/CHANGELOG.md b/l3kernel/CHANGELOG.md
index 0ba7dd1..8cf575c 100644
--- a/l3kernel/CHANGELOG.md
+++ b/l3kernel/CHANGELOG.md
@@ -11,6 +11,10 @@ this project uses date-based 'snapshot' version identifiers.
 
 - `\str_log:n`, `\str_log:N`
 
+### Changed
+
+- Return values from `\sys_shell_get:nnN`
+
 ## [2019-02-15]
 
 ### Changed
diff --git a/l3kernel/l3candidates.dtx b/l3kernel/l3candidates.dtx
index e0a2b21..3bba626 100644
--- a/l3kernel/l3candidates.dtx
+++ b/l3kernel/l3candidates.dtx
@@ -873,7 +873,7 @@
 %
 % \section{Additions to \pkg{l3sys}}
 %
-% \begin{function}[added = 2019-01-16]{\sys_shell_get:nnN}
+% \begin{function}[added = 2019-01-16, updated = 2019-02-16]{\sys_shell_get:nnN}
 % \begin{function}[TF,added = 2019-01-16]{\sys_shell_get:nnN}
 %   \begin{syntax}
 %     \cs{sys_shell_get:nnN} \Arg{shell~command} \Arg{setup} \meta{tl~var}
@@ -884,7 +884,8 @@
 %   \cs{tl_to_str:n}.  Category codes may need to be set appropriately
 %   via the \meta{setup} argument, which is run just before running the
 %   \meta{shell command} (in a group).
-%   If shell escape is disabled, the \meta{tl~var} will be empty.
+%   If shell escape is disabled, the \meta{tl~var} will be set to
+%   |\q_no_value| in the non-branching version.
 %   Note that quote characters (|"|) \emph{cannot} be used inside the
 %   \meta{shell command}.  The \cs{sys_shell_get:nnNTF} conditional
 %   returns \texttt{true} if the shell is available and no quote is
@@ -3045,7 +3046,7 @@
 \cs_new_protected:Npn \sys_shell_get:nnN #1#2#3
   {
     \sys_shell_get:nnNF {#1} {#2} #3
-      { \tl_clear:N #3 }
+      { \tl_set:Nn #3 { \q_no_value } }
   }
 \prg_new_protected_conditional:Npnn \sys_shell_get:nnN #1#2#3 { T , F , TF }
   {