These tests are "native" to Tvix and exist in addition to the Nix test suite.

All of these are straightforward code snippets which are expected to produce a certain result.

identity-* tests

Files named identity-*.nix contain code that is supposed to produce itself exactly after evaluation.

These are useful for testing literals.

eval-okay-* tests

Files named eval-okay-*.nix contain code which is supposed to evaluate to the output in the corresponding eval-okay-*.exp file.

This convention is taken from the original Nix test suite.