These tests verify interactions between the database engine and TVFs.
They happen to use generate_series, but they are not intended to test
the behavior of any specific extension. Tests that verify generate_series
specific behavior remain in extensions.py.
There is a distinction between tests that verify extension-specific
behavior and tests that verify interactions between the database engine
and extensions. Previously, both types of tests were kept in extensions.py.
With this new framework, we can extract the latter type of tests from
extensions.py into TCL. This cleans up extensions.py and provides
compatibility testing with SQLite at no extra cost.
To demonstrate the framework’s usage, tests verifying the handling of
virtual tables were extracted to TCL.
In the future, we may consider moving extension-specific tests to TCL as
well, especially those that have counterparts in SQLite or sqlean.
