[MacPorts] #63534: Installing old version of port fails with "Can't map the URL 'file://.' to a port description file"

[MacPorts]

#63534: Installing old version of port fails with "Can't map the URL 'file://.' to
a port description file"
-----------------------+--------------------
 Reporter:  essandess  |      Owner:  (none)
     Type:  defect     |     Status:  new
 Priority:  Normal     |  Milestone:
Component:  ports      |    Version:  2.7.1
 Keywords:             |       Port:
-----------------------+--------------------
 I'm trying to install the previous version of port {{{google-glog}}} to
 (temporarily) address an issue building {{{pytorch}}}
 (https://trac.macports.org/ticket/62921).

 I've followed these instructions on my local repo:
 https://trac.macports.org/wiki/howto/InstallingOlderPort
 {{{
 git checkout master && git fetch --all && git merge upstream/master && git
 push
 git checkout 055ddcb475c444d137c5412dce86a167d59d6b4c
 cd devel/google-glog
 sudo port install
 }}}

 Error:

 {{{
 Can't map the URL 'file://.' to a port description file ("wrong # args:
 should be "source ?-encoding name? fileName"").
 Please verify that the directory and portfile syntax are correct.
 To use the current port, you must be in a port's directory.
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/63534>
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