hooks-available: avoid some errors with empty repositories

[config/vcsh.git] / .config / vcsh / hooks-available / populate-sparsely.sh

diff --git a/.config/vcsh/hooks-available/populate-sparsely.sh b/.config/vcsh/hooks-available/populate-sparsely.sh
index a49e4b4..33c1fb0 100755 (executable)
--- a/.config/vcsh/hooks-available/populate-sparsely.sh
+++ b/.config/vcsh/hooks-available/populate-sparsely.sh
@@ -2,16 +2,28 @@
 
 set -e
 
-# Only the same instance of vcsh that had the work dir fully populated is
+# Only the same instance of vcsh that had the working tree fully populated is
 # allowed to repopulate it sparsely.
 LOCKDIR=/run/lock/vcsh
+
+# If LOCKDIR does not exist it means that the lock is not active so there's no
+# need to do anything.
+[ -d "$LOCKDIR" ] || exit 0
+
 LOCKPID=$(cat "$LOCKDIR/pid")
 # Use the parent pid because the hooks are launched as children of vcsh.
 [ "$LOCKPID" = $PPID ] || { echo "Repository entered from another vcsh instance. Aborting." 1>&2; exit 1; }
 
 : "${XDG_CONFIG_HOME:="$HOME/.config"}"
 . "$XDG_CONFIG_HOME/vcsh/hooks-available/sparse-checkout.sh"
-git read-tree -mu HEAD
 
-# Unlock the work dir.
+# Verify if the current branch is valid before updating the working tree.
+# This avoids errors with empty repositories which would only confuse the
+# user.
+if git rev-parse --verify HEAD >/dev/null 2>&1;
+then
+  git read-tree -mu HEAD
+fi
+
+# Unlock the working tree.
 rm -rf "$LOCKDIR"