Merge pull request #5840 from dnmfarrell/dnmfarrell/arvo-dojo-check-dir-exists-before-switch

dojo: check =dir exists before switching

pkg/arvo/app/dojo.hoon

@@ -568,6 +568,8 @@
                       ?:  ?=([@ ~] pax)  ~[i.pax %base '0']
                       ?:  ?=([@ @ ~] pax)  ~[i.pax i.t.pax '0']
                       pax
+                  ?:  =(~ .^((list path) %ct pax))
+                    +(..dy (he-diff %tan 'dojo: dir does not exist' ~))
                   =.  dir  (need (de-beam pax))
                   =-  +>(..dy (he-diff %tan - ~))
                   rose+[" " `~]^~[leaf+"=%" (smyt (en-beam he-beak s.dir))]