Custom generic tests

Beyond built-in generic tests, you can write custom generic tests to cover complex testing scenarios.

At bottom, generic tests are Jinja macros that return failing rows. These tests are considered project-level assets and can be used across different models in your project.

To define a generic test, simply write a macro and wrap it within {% test %} {% endtest %} block. A generic test should accept one or both standard parameters:

• model: The model or resource where the test is applied.

• column_name: If the test validates assumptions about a specific column's data, include the column_name parameter.

Here's an example:

This payment_amount_reasonable test receives four parameters: the model, column name, minimum and maximum amounts. Inside, the validation logic is organized into a CTE (common table expression) that queries all the payment amounts not in the reasonable range.

We can apply this generic test to models that store payment amount of different kinds.

-- custom generic test for the reasonable payment amount

{% test payment_amount_reasonable(model, column_name, min_amount=0, max_amount=200) %}

with validation as (
    select
        {{ column_name }} as payment_amount
    from {{ model }}
    where {{ column_name }} < {{ min_amount }}
        or {{ column_name }} > {{ max_amount }}
)

select *
from validation

{% endtest %}

Create a custom generic test

To create a custom generic test, follow these steps:

1. In your project, go to Library > Generic Test.

2. Click + Add new.

3. Define the generic test with the following fields:

   • SQL Code: provide the test code.

   • Parameter: hit the Refresh button to fetch the parameters involved in the test definition and provide the type.

   • Description: describe the functionality of the test.

   • Category: select the test category that the test should reflect.

   
4. Click Add.

Add a custom generic test

The created generic test is then accessible from Test case template. You set up the test the same way as a built-in generic test.

Specify parameter values in the Configuration section:

• Generic Test: Select the desired generic test from the dropdown menu.

• Test Category: Assign an appropriate category to the test based on its nature.

• Configuration: The test script will be automatically populated when you select a generic test from the dropdown.

• Parameters: Provide the parameter values.

Once added, you can verify the test by running the model in Console.