fix some bug when running jenv uninitialized

libexec/jenv

@@ -28,6 +28,7 @@ resolvepath() {
 }
 
 samedir()  {
+  if [ -d $1 ] && [ -d $2 ]; then
   local path1="$(resolvepath $1)"
   local path2="$(resolvepath $2)"
 
@@ -36,6 +37,8 @@ samedir()  {
   else
    return 1;
   fi
+fi
+return 0;
 }
 
 if [ -z "${JENV_ROOT}" ]; then

libexec/jenv---version

@@ -14,8 +14,10 @@ set -e
 
 version="0.4.0"
 
+if [ -d $JENV_ROOT ]; then
 cd "$JENV_ROOT"
 git_revision="$(git describe --tags HEAD 2>/dev/null || true)"
 git_revision="${git_revision#v}"
+fi
 
 echo "jenv ${git_revision:-$version}"