[DEV-260] Don't update parents on initBlockNode (#114)

* [DEV-260] Don't update parents on initBlockNode

* [DEV-260] move addNodeAsChildToParents to blockdag/common_test.go

* [DEV-260] update newProvisionalNode comment

blockdag/blockindex.go

@@ -138,19 +138,12 @@ func initBlockNode(node *blockNode, blockHeader *wire.BlockHeader, parents block
 	}
 
 	if len(parents) > 0 {
-		addNodeAsChildToParents(node)
 		node.blues, node.selectedParent, node.blueScore = phantom(node, phantomK)
 		node.height = calculateNodeHeight(node)
 		node.workSum = node.workSum.Add(node.selectedParent.workSum, node.workSum)
 	}
 }
 
-func addNodeAsChildToParents(node *blockNode) {
-	for _, parent := range node.parents {
-		parent.children.add(node)
-	}
-}
-
 func calculateNodeHeight(node *blockNode) int32 {
 	return node.parents.maxHeight() + 1
 }

blockdag/common_test.go

@@ -193,3 +193,9 @@ func newTestNode(parents blockSet, blockVersion int32, bits uint32, timestamp ti
 	}
 	return newBlockNode(header, parents, phantomK)
 }
+
+func addNodeAsChildToParents(node *blockNode) {
+	for _, parent := range node.parents {
+		parent.children.add(node)
+	}
+}

blockdag/dag.go

@@ -568,7 +568,7 @@ func (dag *BlockDAG) applyUTXOChanges(node *blockNode, block *util.Block, fastAd
 	// fail if the block is not valid, thus bringing all the affected nodes (and the virtual)
 	// into an undefined state.
 	provisionalSet := newProvisionalNodeSet()
-	newNodeProvisional := provisionalSet.newProvisionalNode(node, true, block.Transactions())
+	newNodeProvisional := provisionalSet.newProvisionalNode(node, true, true, block.Transactions())
 
 	// Clone the virtual block so that we don't modify the existing one.
 	virtualClone := dag.virtual.clone()
@@ -591,7 +591,7 @@ func (dag *BlockDAG) applyUTXOChanges(node *blockNode, block *util.Block, fastAd
 	virtualClone.AddTip(node)
 
 	// Build a UTXO set for the new virtual block and update the DAG tips' diffs.
-	virtualNodeProvisional := provisionalSet.newProvisionalNode(&virtualClone.blockNode, true, nil)
+	virtualNodeProvisional := provisionalSet.newProvisionalNode(&virtualClone.blockNode, true, true, nil)
 	newVirtualUTXO, _, err := virtualNodeProvisional.pastUTXO(virtualClone, dag.db)
 	if err != nil {
 		newErrString := fmt.Sprintf("could not restore past UTXO for virtual %v: %s", virtualClone, err)
@@ -667,9 +667,9 @@ type provisionalNode struct {
 }
 
 // newProvisionalNode takes a node and builds a provisionalNode from it.
-// To avoid building the entire DAG in provisionalNode format we pass withRelatives = true
+// To avoid building the entire DAG in provisionalNode format we pass withParents = true or withChildren = true,
-// only when the node's relatives (parents and children) are required.
+// only when the node's relatives (parents or children) are required.
-func (pns provisionalNodeSet) newProvisionalNode(node *blockNode, withRelatives bool,
+func (pns provisionalNodeSet) newProvisionalNode(node *blockNode, withParents bool, withChildren bool,
 	transactions []*util.Tx) *provisionalNode {
 	if existingProvisional, ok := pns[node.hash]; ok {
 		return existingProvisional
@@ -683,23 +683,26 @@ func (pns provisionalNodeSet) newProvisionalNode(node *blockNode, withRelatives
 		pns[node.hash] = provisional
 	}
 
-	if withRelatives {
+	if withParents {
 		provisional.parents = []*provisionalNode{}
 		for _, parent := range node.parents {
-			provisional.parents = append(provisional.parents, pns.newProvisionalNode(parent, false, nil))
+			provisional.parents = append(provisional.parents, pns.newProvisionalNode(parent, false, true, nil))
 		}
 		if node.selectedParent != nil {
 			provisional.selectedParent = pns[node.selectedParent.hash]
 		}
+	}
 
+	if withChildren {
 		provisional.children = []*provisionalNode{}
 		for _, child := range node.children {
-			provisional.children = append(provisional.children, pns.newProvisionalNode(child, false, nil))
+			provisional.children = append(provisional.children, pns.newProvisionalNode(child, false, false, nil))
 		}
 		if node.diffChild != nil {
 			provisional.diffChild = pns[node.diffChild.hash]
 		}
 	}
+
 	if node.diff != nil {
 		provisional.diff = node.diff.clone()
 	}

blockdag/phantom_test.go

@@ -831,6 +831,8 @@ func TestPhantom(t *testing.T) {
 			}
 
 			blockDAG.index.AddNode(node)
+			addNodeAsChildToParents(node)
+
 			blockByIDMap[blockData.id] = node
 			idByBlockMap[node] = blockData.id
 

blockdag/virtualblock_test.go

@@ -94,6 +94,7 @@ func TestVirtualBlock(t *testing.T) {
 
 		// Add all blockNodes in tipsToAdd in order
 		for _, tipToAdd := range test.tipsToAdd {
+			addNodeAsChildToParents(tipToAdd)
 			virtual.AddTip(tipToAdd)
 		}