Only generate CommD for what was given, not full sector

I misread the original code ( again - we have no tests :/ )

Author: ribasushi

nonffi/commd.go

@@ -1,6 +1,7 @@
 package nonffi
 
 import (
+	"errors"
 	"fmt"
 	"math/bits"
 
@@ -16,18 +17,18 @@ func GenerateUnsealedCID(proofType abi.RegisteredSealProof, pieces []abi.PieceIn
 	if !found {
 		return cid.Undef, fmt.Errorf("unknown seal proof type %d", proofType)
 	}
-
-	target := abi.PaddedPieceSize(spi.SectorSize)
 	if len(pieces) == 0 {
-		return zerocomm.ZeroPieceCommitment(target.Unpadded()), nil
+		return cid.Undef, errors.New("no pieces provided")
 	}
 
+	maxSize := abi.PaddedPieceSize(spi.SectorSize)
+
 	// sancheck everything
 	for i, p := range pieces {
 		if p.Size < 128 {
 			return cid.Undef, fmt.Errorf("invalid Size of PieceInfo %d: value %d is too small", i, p.Size)
 		}
-		if pieces[i].Size > target {
+		if pieces[i].Size > maxSize {
 			return cid.Undef, fmt.Errorf("invalid Size of PieceInfo %d: value %d is larger than sector size of SealProofType %d", i, p.Size, proofType)
 		}
 		if bits.OnesCount64(uint64(p.Size)) != 1 {
@@ -68,7 +69,7 @@ func GenerateUnsealedCID(proofType abi.RegisteredSealProof, pieces []abi.PieceIn
 		)
 	}
 
-	for len(stack) > 1 || stack[0].Size < target {
+	for len(stack) > 1 {
 		lastSize := stack[len(stack)-1].Size
 		stack = reduceStack(
 			append(
@@ -81,7 +82,7 @@ func GenerateUnsealedCID(proofType abi.RegisteredSealProof, pieces []abi.PieceIn
 		)
 	}
 
-	if stack[0].Size > target {
+	if stack[0].Size > maxSize {
 		return cid.Undef, fmt.Errorf("provided pieces sum up to %d bytes, which is larger than sector size of SealProofType %d", stack[0].Size, proofType)
 	}
 

nonffi/commd_test.go

@@ -3,6 +3,7 @@ package nonffi
 import (
 	"testing"
 
+	"github.com/filecoin-project/go-commp-utils/zerocomm"
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/ipfs/go-cid"
 )
@@ -37,6 +38,10 @@ func TestGenerateUnsealedCID(t *testing.T) {
 			{PieceCID: cidMustParse("baga6ea4seaqa3qbabsbmvk5er6rhsjzt74beplzgulthamm22jue4zgqcuszofi"), Size: 1024 << 20}, // https://filfox.info/en/deal/3755803
 			{PieceCID: cidMustParse("baga6ea4seaqiekvf623muj6jpxg6vsqaikyw3r4ob5u7363z7zcaixqvfqsc2ji"), Size: 256 << 20},  // https://filfox.info/en/deal/3755883
 			{PieceCID: cidMustParse("baga6ea4seaqhsewv65z2d4m5o4vo65vl5o6z4bcegdvgnusvlt7rao44gro36pi"), Size: 512 << 20},  // https://filfox.info/en/deal/3755882
+
+			// GenerateUnsealedCID does not "fill a sector", do it here to match the SP provided sector commD
+			{PieceCID: zerocomm.ZeroPieceCommitment(abi.PaddedPieceSize(8 << 30).Unpadded()), Size: 8 << 30},
+			{PieceCID: zerocomm.ZeroPieceCommitment(abi.PaddedPieceSize(16 << 30).Unpadded()), Size: 16 << 30},
 		},
 	)