Test scenarios for referenda that fail due to missing deposits or insufficient support/approval. These tests cover all negative outcomes that can actually happen in pallet_referenda.

• Missing decision deposit

  • Submit a referendum without paying the decision deposit.
  • Ensure it never enters Deciding and is automatically rejected or cleaned up after the undeciding timeout.
  • Check correct events (TimedOut, DepositRefunded/Slashed) and state transitions.

• Insufficient support

  • Enter Deciding phase with decision deposit paid.
  • Cast votes so that support (proportion of aye vs possible votes) stays below the track’s minimum support threshold.
  • Expected outcome: referendum rejected for insufficient support.

• Insufficient approval

  • Enter Deciding phase with decision deposit paid.
  • Cast votes so support meets the minimum, but approval (vote-weight adjusted) is below the track’s required approval curve.
  • Expected outcome: referendum rejected for insufficient approval.

• Track capacity / queue overflow (optional)

  • Submit more referenda than max_deciding allows.
  • Verify that queued referenda are handled correctly

• Assertions for all scenarios

  • Correct state transitions: Submitted → deposit → Deciding → Rejected / TimedOut.
  • Correct events emitted: DecisionDepositPlaced, DecisionStarted, Rejected, TimedOut, DepositRefunded / DepositSlashed.
  • Correct application of track curves for support and approval.
  • Deposit refund or slashing behaves according to outcome.