skip unsettleable rails

Author: LexLuthr

pdp/contract/FWSS/settle_resolver.go

@@ -105,6 +105,10 @@ func pdpSettleTarget(rail filecoinpayment.PaymentsRailView, currentEpoch, activa
 		return nil, false
 	}
 
+	if shouldSkipFWSSActivationTerminationBoundary(rail, activationEpoch) {
+		return nil, false
+	}
+
 	if activationEpoch != nil && activationEpoch.Sign() > 0 {
 		if maxProvingPeriod == nil || maxProvingPeriod.Sign() <= 0 {
 			return nil, false
@@ -142,3 +146,23 @@ func pdpSettleTarget(rail filecoinpayment.PaymentsRailView, currentEpoch, activa
 
 	return target, true
 }
+
+// shouldSkipFWSSActivationTerminationBoundary is a temporary FWSS contract
+// workaround. When a terminated PDP rail ends exactly at proving activation,
+// FWSS accepts toEpoch == activationEpoch in its outer range check but then
+// treats the same epoch as an invalid proving period internally. Lower targets
+// are also invalid for that rail, so Curio has no settlement epoch to submit
+// until the contract edge case is fixed.
+func shouldSkipFWSSActivationTerminationBoundary(rail filecoinpayment.PaymentsRailView, activationEpoch *big.Int) bool {
+	if activationEpoch == nil || activationEpoch.Sign() <= 0 {
+		return false
+	}
+	if rail.SettledUpTo == nil || rail.EndEpoch == nil || rail.EndEpoch.Sign() <= 0 {
+		return false
+	}
+	if rail.EndEpoch.Cmp(activationEpoch) != 0 {
+		return false
+	}
+
+	return rail.SettledUpTo.Cmp(rail.EndEpoch) < 0
+}

pdp/contract/FWSS/settle_resolver_test.go

@@ -125,6 +125,15 @@ func TestFWSSPDPSettleTarget(t *testing.T) {
 			wantTarget:     900,
 			wantResolvable: true,
 		},
+		{
+			name:           "terminated rail ending at activation is skipped for FWSS contract bug",
+			settledUpTo:    997,
+			endEpoch:       1000,
+			currentEpoch:   7000,
+			activation:     1000,
+			provingPeriod:  2880,
+			wantResolvable: false,
+		},
 		{
 			name:           "no progress skips settlement",
 			settledUpTo:    6760,