salt: winrepo-ng jinjia2 compilation error is too quiet - needs "displaying"

see new comment below here https://github.com/saltstack/salt/issues/34781#issuecomment-233854043, this turned out to be another case where a jinjja2 template compilation simply failed silently with no info whatsoever being displayed.:

Description of Issue/Question

@twangboy help I just cannot get it to use some newly added winrepo-ng pkg files to install them. Pretty sure I am not doing anything wrong or different from previous versions.

Setup

I create a new winrepo-ng file on the saltstack github site (as usual), then I git update my master and refresh_db my windows minions, but pkg.install my-brand-new-pkg, reports that said pkg cannot be located. Although I can see the file being copied to the cache during the refresh_db cmd. but a pgk.get_repo_data does indeed not show me the newly added pkg.

Steps to Reproduce Issue

salt my-win-minion pkg.refresh_db salt my-win-minion pkg.install check_mk-agent-msi and it cannot locate the check_mk-agent-msi file. (Note: there is a number of check-mk-agent* pkgs, 'check-mk' not 'check_mk' they are ‘older’ and I need to test some new ones under the name of ‘check_mk-agent-msi’)

Versions Report

both master and minion are running on 2016.3.1