undefined method 'import' when assets:precompile in prod

[rossjones]

When I run assets:precompile for our prod environment

RAILS_ENV=production bin/rake assets:precompile  --trace

I get the following error ...

4: from bin/rake:3:in `<main>'
3: from bin/rake:3:in `require'
2: from ...ruby-2.6.3@.../gems/turnout-2.5.0/lib/turnout/rake_tasks.rb:3:in `<top (required)>'
1: from from ...ruby-2.6.3@.../gems/turnout-2.5.0/lib/turnout/rake_tasks.rb:3:in `each'
from ...ruby-2.6.3@.../gems/turnout-2.5.0/lib/turnout/rake_tasks.rb:3:in 
`block in <top (required)>': undefined method `import' for main:Object (NoMethodError

I'm not sure why assets:precompile is doing this in Rails 5.2.3 but presumably I'm doing something wrong.

[rossjones]

This appears to have been a false alarm. Another error elsewhere content_security_policy seems to have been swallowed and for some reason raised it's head this way.