Override any existing environment variables

[mpessas]

The commit instructs dotenv to override any variables that already exist in the environment, so that the ones we define for pytest take precedence over any defaults defined e.g. in a docker-based setup.

[mpessas]

I was trying pytest-dotenv and noticed that the variables I would define in the .env file used for testing would not override the ones already defined by docker-compose. This creates a problem for me, given that the goal is exactly that: have tests run with their own set of variables no matter what is or is not in the environment already.

[quiqua]

So in your docker-compose you have something like:

my-app:
  env_file:
    - production.env

And your container also contains a .env file which has different contents, so you want to override them?

Or do you configure them via:

my-app:
  environment:
    - FOO=bar

Also this seems somehow related: https://stackoverflow.com/questions/29062522/different-env-file-but-same-yml-with-docker-compose#comment80776332_29063882

I'll just try to understand your use-case a bit further: are you just running the tests when you trigger docker-compose up|start ?

[mpessas]

I do docker-compose run --rm <container> pytest. The docker-compose file defines its own set of variables, which I'd like to override for the test suite.

[mpessas]

I still used the prefix env_ as a namespace, so as to avoid any name collision with other plugins.