plugins/nodenv: use `_command_exists`

clean_files.txt

@@ -90,6 +90,7 @@ plugins/available/history.plugin.bash
 plugins/available/hub.plugin.bash
 plugins/available/jump.plugin.bash
 plugins/available/node.plugin.bash
+plugins/available/nodenv.plugin.bash
 plugins/available/plenv.plugin.bash
 plugins/available/pyenv.plugin.bash
 plugins/available/rbenv.plugin.bash

plugins/available/nodenv.plugin.bash

@@ -1,7 +1,10 @@
+# shellcheck shell=bash
 cite about-plugin
 about-plugin 'load nodenv, if you are using it'
 
 export NODENV_ROOT="$HOME/.nodenv"
 pathmunge "$NODENV_ROOT/bin"
 
-[[ `which nodenv` ]] && eval "$(nodenv init - bash)"
+if _command_exists nodenv; then
+	eval "$(nodenv init - bash)"
+fi