wcl.txt

Note, these test cases are designed such that you can write while loops and randomly vary the # of shares and the price once you've written the first one of each [as long as the price you specify is within the range] and the math'll add up.

Filling a bid [so selling]:

    creator escrowed shares in all outcomes except this one, filler does not have shares in this outcome /// creator is closing a short position, filler is going short:

        - The creator has n shares escrowed in every outcome except the one bidding on and is wanting to buy them at price x for a total of (x - min)*n ETH. Filler fills the bid and should pay a cost of (max - x)*n ETH [since they're shorting]. The filler doesn't have shares so complete sets need to be issued by combining the (x - min)*n from the creator + (max - x)*n from the filler [which makes range] ETH. The creator gets shares in the outcome they're missing, which completes their sets which are sold for range eth, and they then get to keep (max - x)*n ETH, the other part of the range (x-min)*n is used to issue the filler's complete set. N shares of every outcome except the one being sold go to the filler, the n being sold go to the creator.

    creator escrowed cash, filler does not have shares in this outcome /// creator is going long, filler is going short:

        - The creator is placing a bid for n shares at x each, costing them (x - min)*n ETH in escrow with the market. The filler fills the bid and has to pay (max - x)*n ETH total to the market. They get paid (x-min)*n ETH from the creator and need to pay (max - x)*n more ETH to the market + that (x-min)*n from the creator, and complete sets are issued.  Then the creator gets n of the outcome and n of every other outcome go to the filler.

    creator escrowed shares in all outcomes except this one, filler has shares in this outcome /// creator is closing a short position, filler is closing a long position:

        - The creator is placing a bid for n shares at x each and has shares escrowed in every outcome except the one bidding on. Filler fills the bid at x for n shares and has n shares. These n shares are sent to the creator. The creator's now formed complete sets are then sold and (x - min)*n ETH are sent to the filler. The creator ends up with (max - x)*n ETH proceeds after closing their short.

    creator escrowed cash, filler has shares in this outcome /// creator is going long, filler is closing a long position:

        - The creator is placing a bid for n shares at x each, costing them (x - min)*n ETH in escrow with the market. Filler fills the bid at x for n shares and already has n shares. These n shares are sent to the creator. The creator's (x - min)*n ETH are then sent to the filler.

Filling an ask [so buying]:

    creator escrowed shares in this outcome, filler does not have shares in all outcomes except this one /// creator is closing a long position, filler is going long:

        - The creator had n shares escrowed by placing an ask for n shares @ x each. Filler fills an ask at x for n shares, they should spend (price - min)*n ETH on this trade and end up with n more shares of the outcome. The creator should receive (price - min)*n ETH and not have access to those n shares anymore [like they shouldn't be able to cancel their order and get the 10 shares back, they've gone from their account -> market -> filler]. The market should no longer have those n shares in escrow.

    creator escrowed cash, filler does not have shares in all outcomes except this one /// creator is going short, filler is going long:

        - The creator wants to sell n shares and places an ask for n shares @ x each, the creator doesn't own shares so (max - x)*n ETH is escrowed. Filler fills an ask at x for n shares, they should spend (x - min)*n ETH on this trade and end up with n more shares of the outcome. The creator should receive n shares in each outcome except the one they sold. The market should no longer have the creator's (max - x)*n ETH in escrow since they were used with the filler's (x - min)*n ETH to issue a complete set and split it up between the creator and filler. This is effectively short selling by the creator.

    creator escrowed shares in this outcome, filler has shares in all outcomes except this one /// creator is closing a long position, filler is short the outcome and closing:

        - The creator had n shares escrowed by placing an ask for n shares @ x each. Filler fills an ask at x for n shares, they should receive (max - x)*n ETH on this trade and end up with n less shares of every outcome except for no change in the outcome they're buying, the reason is buying this outcome completes a complete set and that is then sold, which essentially closes out a short position. The creator should receive (price - min)*n ETH and not have access to those n shares anymore [like they shouldn't be able to cancel their order and get the n shares back, they've gone from their account -> market -> filler -> complete set sold]. The market should no longer have those n shares in escrow either.

    creator escrowed cash, filler has shares in all outcomes except this one /// creator is going short, filler is short the outcome and closing:

        - The creator wants to sell n shares and places an ask for n shares @ x each, the creator doesn't own shares so (max - x)*n ETH is escrowed. Filler fills an ask at x for n shares, they should receive (max - x)*n ETH on this trade and end up with n less shares of every outcome except for no change in the outcome they're buying, the reason is buying this outcome completes a complete set and that is then sold, which essentially closes out a short position. The creator should receive n shares in each outcome except the one they sold. This is effectively short selling by the creator and closing out a short by the filler. Note, this one is a bit more complex, so more explanation of what is happening under the hood: What happens here is the filler gets the final outcome needed to close their short, which is then sold [the complete sets] and yields range*n ETH. The creator has escrowed (max - x)*n ETH, that's combined with (price - min)*n ETH from the filler's complete set money to then issue n shares in each outcome to the creator who is shorting, except for the one outcome they're shorting. (max - x)*n ETH is left over which is the filler's payment for closing out their short position. Intuitively this makes sense, if you are short outcome x and decide to close your short by buying outcome x back at price x, then your proceeds are (max - x) per share, or (max - x)*n ETH. And as the creator, if you are shorting outcome x at price x, your WCL is (max - x) per share or (max - x)*n ETH as you'd expect.