Function: _matchIncomingAsk(PerpBook ds, Order incomingOrder, bool amountIsBase)

This internal function matches an incoming taker ask order (SELL order) against existing bid orders in the order book. The function walks through available bids starting from the highest bid price, ensuring that the ask fills at the best possible prices for the seller.

It continues matching until the ask amount is fully matched or there are no more available bids with a price greater than or equal to incomingOrder.price.

Branches and code coverage

Intended branches

• The order book is empty, there is no match, and as a result, totalQuoteTokenReceived and totalBaseTokenSent are zero.

  Test coverage

• Correct totalQuoteTokenReceived and totalBaseTokenSent are calculated across multiple matches.

  Test coverage

• The order book contains only one expired order. The expired order is removed without reverting.

  Test coverage

• The order book contains only one eligible order with minimum amount.

  Test coverage

• The incoming ask is fully filled when the taker ask amount equals the bid.

  Test coverage

• The incoming ask is fully filled using multiple bids.

  Test coverage

• The incoming ask is partially filled when the taker ask amount is smaller than the bid. The remaining amount is returned correctly.

  Test coverage

• All bids are lower the taker's limit price — no match.

  Test coverage

• The incoming ask has the same price as the bid limit.

  Test coverage

• totalTakerFeeInQuote is calculated correctly for one match.

  Test coverage

• totalTakerFeeInQuote is calculated correctly for multiple matches.

  Test coverage