Adaptive questions appear to behave incorrectly when a student submits a given answer, followed by an incomplete/invalid answer, and then the original answer again.
Steps to reproduce:
- Create a new quiz using the Adaptive question behavior.
- Create a new numeric question; provide an answer.
- Preview the quiz, and submit a properly-formatted numeric answer. This can be correct or incorrect; this doesn't affect the bug.
- Submit an ungradeable answer, such as something non-numeric.
- Submit the same properly-formatted answer you used for #3.
Expectation: Moodle displays the properly-formatted answer, along with any feedback and relevant marks.
Actual Behaviour: Moodle displays the most recent invalid answer, along with any feedback and relevant marks-- as though the properly-formatted answer was never submitted.
This isn't limited to the Numeric question type-- the issue appears to be with the Adaptive question behaviours.