gnu: tree: Fix problem with no output when fd3 is present.

* gnu/packages/patches/tree-disable-stddata.patch: New file.
* gnu/local.mk (dist_patch_DATA): Adjust accordingly.
* gnu/packages/admin.scm (tree)[source](patches): New field.

gnu/local.mk

@@ -1859,8 +1859,9 @@ dist_patch_DATA =						\
   gnu/packages/patches/tootle-glib-object-naming.patch		\
   gnu/packages/patches/tootle-reason-phrase.patch		\
   %D%/packages/patches/tor-sandbox-i686.patch			\
-  %D%/packages/patches/transcode-ffmpeg.patch	\
+  %D%/packages/patches/transcode-ffmpeg.patch			\
   %D%/packages/patches/transmission-honor-localedir.patch	\
+  %D%/packages/patches/tree-disable-stddata.patch		\
   %D%/packages/patches/tremc-fix-decodestring.patch		\
   %D%/packages/patches/trytond-add-egg-modules-to-path.patch	\
   %D%/packages/patches/trytond-add-guix_trytond_path.patch	\

gnu/packages/admin.scm

@@ -2401,6 +2401,7 @@ recover lost partitions and/or make non-booting disks bootable again.")
               (uri (string-append
                     "http://mama.indstate.edu/users/ice/tree/src/tree-"
                     version ".tgz"))
+              (patches (search-patches "tree-disable-stddata.patch"))
               (sha256
                (base32 "0f92vx6gpz7v29wi9clklzah57v7lgx5kv0m1w4b9xjc35d9qcz3"))))
     (build-system gnu-build-system)

gnu/packages/patches/tree-disable-stddata.patch

@@ -0,0 +1,16 @@
+Tree 2.0.0 and later will write its output in JSON format on fd3 if
+present, instead of the requested output on fd1, which breaks e.g.
+'password-store' tests.  Disable for now; upstream has been notified.
+
+diff --git a/tree.c b/tree.c
+--- a/tree.c
++++ b/tree.c
+@@ -133,7 +133,7 @@ int main(int argc, char **argv)
+   mb_cur_max = 1;
+ #endif
+ 
+-#ifdef __linux__
++#if 0
+   // Output JSON automatically to "stddata" if present:
+   if (fcntl(STDDATA_FILENO, F_GETFD) >= 0) {
+     Jflag = noindent = TRUE;