Ever since enabling automatic testing on Heroku, test runs have been failing after 5-6 minutes of load time. When I look at a specific run in the Tests tab of the pipeline, there’s only a red box saying, “A fatal error occurred running this test node.” There is nothing in the test setup or test outputs. Something is seeming to fail before the tests are even reached, though running the app normally works just fine.

I’ve tried running the command heroku ci:debug on the CLI, but all I get is this output:

Preparing source... done
Creating test run... done
Running setup and attaching to test dyno...
~ $ ci setup && eval $(ci env)
bash: ci: command not found

Here is the current test environment setup in the app.json file:

  "environments": {
    "test": {
      "formation": {
        "test": {
          "quantity": 1,
          "size": "standard-1x"
        }
      },
      "scripts": {
        "test": "pytest tests/"
      },
      "addons": [
        "heroku-postgresql:in-dyno"
      ]
    }
  }

The app is running on a container stack, if that makes any difference.