Feature support multiple test cases

[marcellovictorino]

This is a:

• bug fix PR with no breaking changes
• new functionality
• a breaking change

Description & motivation

Addressing this issue, enables to define a test once, to be applied over multiple test cases.

Applicable when there are multiple test case scenarios, where the mocked input and expected output data (seed) represent a single case, having the seed file names identified by test_case_1, test_case_2 etc.

Checklist

• I have verified that these changes work locally on the following warehouses (Note: it's okay if you do not have access to all warehouses, this helps us understand what has been covered)
  • BigQuery
  • Postgres
  • Redshift
  • Snowflake
• I have updated the README.md (if applicable)
• I have added tests & descriptions to my macros (and models if applicable) -> added descriptions. Not sure how to add tests

Additional comments

1. I am not sure what is the best way to adapt the proposed code change to the new dispatch pattern. I developed these changes against an old package version (v 0.1.2). I marked it with the comment {% FIXME: ...

2. Also, I have changed the get_test macro behavior to always store the mocked model output as a view, which provides better visibility on failing tests. As a view, it is possible to inspect its definition, quickly debugging any issues

Note: this is my first time contributing to an open-source project 🎉! Please let me know if there is anything else I could/should do 👍

[marcellovictorino]

Forgot to tag you here for visibility:
@mjirv

[marcellovictorino]

This model.database/schema will retrieve the value from the model where the test is being applied.
Alternatively, I wanted to use the default value as defined in the dbt_project.yaml, for the seeds. Any idea how to do this?

In my use case, I was able to hard-code the value, but would be nice to have a more elegant solution

[mjirv]

Hey @marcellovictorino. Thanks again for submitting this. Great work, and it will be an awesome feature to add.

I left a few comments in the code. Curious to get your thoughts.

Also, I'm finding it a little hard to review both the "multiple test case" feature and the "save output for inspection" feature all at once. Could you split them into 2 separate PRs?

[marcellovictorino]

Thanks for the review @mjirv . I really appreciate it :)
Been a busy week, but I will perform the required changes before the end of the week (2022-10-14)

[marcellovictorino]

Closing this in favor of splitting the different features into separate PRs: #56