We like code commits a lot! They're super handy, and they keep the project going and doing the work it needs to do to be useful to others.
Code contributions of just about any size are acceptable!
The main difference between code contributions and documentation contributions is that contributing code requires inclusion of relevant tests for the code being added or changed. Contributions without accompanying tests will be held off until a test is added, unless the maintainers consider the specific tests to be either impossible, or way too much of a burden for such a contribution.