[marketplace] test & fix slotState()

contracts/Marketplace.sol

@@ -247,24 +247,25 @@ contract Marketplace is Collateral, Proofs, StateRetrieval {
     }
   }
 
-  function slotState(SlotId slotId) internal view override returns (SlotState) {
+  function slotState(SlotId slotId) public view override returns (SlotState) {
     Slot storage slot = slots[slotId];
+    if (RequestId.unwrap(slot.requestId) == 0) {
+      return SlotState.Free;
+    }
     RequestState reqState = requestState(slot.requestId);
     if (slot.state == SlotState.Paid) {
       return SlotState.Paid;
-    } else if (
-      slot.state == SlotState.Failed || reqState == RequestState.Failed
-    ) {
-      return SlotState.Failed;
-    } else if (
-      slot.state == SlotState.Finished ||
-      reqState == RequestState.Finished ||
-      reqState == RequestState.Cancelled
-    ) {
-      return SlotState.Finished;
-    } else {
-      return slot.state;
     }
+    if (reqState == RequestState.Cancelled) {
+      return SlotState.Finished;
+    }
+    if (reqState == RequestState.Finished) {
+      return SlotState.Finished;
+    }
+    if (reqState == RequestState.Failed) {
+      return SlotState.Failed;
+    }
+    return slot.state;
   }
 
   struct RequestContext {

contracts/Proofs.sol

@@ -19,7 +19,7 @@ abstract contract Proofs is Periods {
   mapping(SlotId => mapping(Period => bool)) private received;
   mapping(SlotId => mapping(Period => bool)) private missing;
 
-  function slotState(SlotId id) internal view virtual returns (SlotState);
+  function slotState(SlotId id) public view virtual returns (SlotState);
 
   function missingProofs(SlotId slotId) public view returns (uint256) {
     return missed[slotId];

contracts/Requests.sol

@@ -46,10 +46,10 @@ enum RequestState {
 }
 
 enum SlotState {
-  Free, // [default] not filled yet, or host has freed slot
+  Free, // [default] not filled yet, or host has vacated the slot
   Filled, // host has filled slot
   Finished, // successfully completed
-  Failed, // host has missed too many proofs
+  Failed, // the request has failed
   Paid // host has been paid
 }
 

contracts/TestMarketplace.sol

@@ -8,10 +8,9 @@ contract TestMarketplace is Marketplace {
   constructor(
     IERC20 token,
     MarketplaceConfig memory config
-  ) Marketplace(token, config) // solhint-disable-next-line no-empty-blocks
+  )
-  {
+    Marketplace(token, config) // solhint-disable-next-line no-empty-blocks
-
+  {}
-  }
 
   function forciblyFreeSlot(SlotId slotId) public {
     _forciblyFreeSlot(slotId);

contracts/TestProofs.sol

@@ -10,7 +10,7 @@ contract TestProofs is Proofs {
   // solhint-disable-next-line no-empty-blocks
   constructor(ProofConfig memory config) Proofs(config) {}
 
-  function slotState(SlotId slotId) internal view override returns (SlotState) {
+  function slotState(SlotId slotId) public view override returns (SlotState) {
     return states[slotId];
   }
 

test/Marketplace.test.js

@@ -6,7 +6,7 @@ const { expect } = require("chai")
 const { exampleConfiguration, exampleRequest } = require("./examples")
 const { periodic, hours } = require("./time")
 const { requestId, slotId, askToArray } = require("./ids")
-const { RequestState } = require("./requests")
+const { RequestState, SlotState } = require("./requests")
 const {
   waitUntilCancelled,
   waitUntilStarted,
@@ -548,6 +548,86 @@ describe("Marketplace", function () {
     })
   })
 
+  describe("slot state", function () {
+    const { Free, Filled, Finished, Failed, Paid } = SlotState
+    let period, periodEnd
+
+    beforeEach(async function () {
+      period = config.proofs.period
+      ;({ periodOf, periodEnd } = periodic(period))
+
+      switchAccount(client)
+      await token.approve(marketplace.address, price(request))
+      await marketplace.requestStorage(request)
+      switchAccount(host)
+      await token.approve(marketplace.address, config.collateral.initialAmount)
+      await marketplace.deposit(config.collateral.initialAmount)
+    })
+
+    async function waitUntilProofIsRequired(id) {
+      await advanceTimeTo(periodEnd(periodOf(await currentTime())))
+      while (
+        !(
+          (await marketplace.isProofRequired(id)) &&
+          (await marketplace.getPointer(id)) < 250
+        )
+      ) {
+        await advanceTime(period)
+      }
+    }
+
+    it("is 'Free' initially", async function () {
+      expect(await marketplace.slotState(slotId(slot))).to.equal(Free)
+    })
+
+    it("changes to 'Filled' when slot is filled", async function () {
+      await marketplace.fillSlot(slot.request, slot.index, proof)
+      expect(await marketplace.slotState(slotId(slot))).to.equal(Filled)
+    })
+
+    it("changes to 'Finished' when request finishes", async function () {
+      await waitUntilStarted(marketplace, request, proof)
+      await waitUntilFinished(marketplace, slot.request)
+      expect(await marketplace.slotState(slotId(slot))).to.equal(Finished)
+    })
+
+    it("changes to 'Finished' when request is cancelled", async function () {
+      await marketplace.fillSlot(slot.request, slot.index, proof)
+      await waitUntilCancelled(request)
+      expect(await marketplace.slotState(slotId(slot))).to.equal(Finished)
+    })
+
+    it("changes to 'Free' when host frees the slot", async function () {
+      await marketplace.fillSlot(slot.request, slot.index, proof)
+      await marketplace.freeSlot(slotId(slot))
+      expect(await marketplace.slotState(slotId(slot))).to.equal(Free)
+    })
+
+    it("changes to 'Free' when too many proofs are missed", async function () {
+      await waitUntilStarted(marketplace, request, proof)
+      while ((await marketplace.slotState(slotId(slot))) === Filled) {
+        await waitUntilProofIsRequired(slotId(slot))
+        const missedPeriod = periodOf(await currentTime())
+        await advanceTime(period)
+        await marketplace.markProofAsMissing(slotId(slot), missedPeriod)
+      }
+      expect(await marketplace.slotState(slotId(slot))).to.equal(Free)
+    })
+
+    it("changes to 'Failed' when request fails", async function () {
+      await waitUntilStarted(marketplace, request, proof)
+      await waitUntilSlotFailed(marketplace, request, slot)
+      expect(await marketplace.slotState(slotId(slot))).to.equal(Failed)
+    })
+
+    it("changes to 'Paid' when host has been paid", async function () {
+      await waitUntilStarted(marketplace, request, proof)
+      await waitUntilFinished(marketplace, slot.request)
+      await marketplace.freeSlot(slotId(slot))
+      expect(await marketplace.slotState(slotId(slot))).to.equal(Paid)
+    })
+  })
+
   describe("proof requirements", function () {
     let period, periodOf, periodEnd
 

test/requests.js

@@ -10,6 +10,8 @@ const SlotState = {
   Free: 0,
   Filled: 1,
   Finished: 2,
+  Failed: 3,
+  Paid: 4,
 }
 
 module.exports = { RequestState, SlotState }