nits

snow/engine/avalanche/vertex_heap.go

@@ -18,13 +18,14 @@ type priorityQueue []*vertexItem
 
 func (pq priorityQueue) Len() int { return len(pq) }
 
+// Returns true if the vertex at index i has greater height than the vertex at
+// index j.
 func (pq priorityQueue) Less(i, j int) bool {
 	statusI := pq[i].vertex.Status()
 	statusJ := pq[j].vertex.Status()
 
-	// Put unknown vertices at the front of the heap to ensure
-	// once we have made it below a certain height in DAG traversal
-	// we do not need to reset
+	// Put unknown vertices at the front of the heap to ensure once we have made
+	// it below a certain height in DAG traversal we do not need to reset
 	if !statusI.Fetched() {
 		return true
 	}
@@ -40,6 +41,7 @@ func (pq priorityQueue) Swap(i, j int) {
 	pq[j].index = j
 }
 
+// Push adds an item to this priority queue. x must have type *vertexItem
 func (pq *priorityQueue) Push(x interface{}) {
 	n := len(*pq)
 	item := x.(*vertexItem)
@@ -47,6 +49,7 @@ func (pq *priorityQueue) Push(x interface{}) {
 	*pq = append(*pq, item)
 }
 
+// Pop returns the last item in this priorityQueue
 func (pq *priorityQueue) Pop() interface{} {
 	old := *pq
 	n := len(old)
@@ -84,6 +87,8 @@ func (vh *maxHeightVertexHeap) Clear() {
 	vh.elementIDs.Clear()
 }
 
+// Push adds an element to this heap. Returns true if the element was added.
+// Returns false if it was already in the heap.
 func (vh *maxHeightVertexHeap) Push(vtx avalanche.Vertex) bool {
 	vtxID := vtx.ID()
 	if vh.elementIDs.Contains(vtxID) {
@@ -98,6 +103,9 @@ func (vh *maxHeightVertexHeap) Push(vtx avalanche.Vertex) bool {
 	return true
 }
 
+// If there are any vertices in this heap with status Unknown, removes one such
+// vertex and returns it. Otherwise, removes and returns the vertex in this heap
+// with the greatest height.
 func (vh *maxHeightVertexHeap) Pop() avalanche.Vertex {
 	vtx := heap.Pop(vh.heap).(*vertexItem).vertex
 	vh.elementIDs.Remove(vtx.ID())

snow/engine/avalanche/vertex_heap_test.go

@@ -49,7 +49,7 @@ func TestUniqueVertexHeapReturnsOrdered(t *testing.T) {
 
 	vtxZ := h.Pop()
 	if !vtxZ.ID().Equals(vtx4.ID()) {
-		t.Fatalf("Heap did not pop unknonw element first")
+		t.Fatalf("Heap did not pop unknown element first")
 	}
 
 	vtxA := h.Pop()

snow/engine/common/vm.go

@@ -36,10 +36,10 @@ type VM interface {
 		fxs []*Fx,
 	) error
 
-	// Bootstrapping is called when the node is starting to bootstrap.
+	// Bootstrapping is called when the node is starting to bootstrap this chain.
 	Bootstrapping() error
 
-	// Bootstrapped is called when the node is exiting bootstrapping.
+	// Bootstrapped is called when the node is done bootstrapping this chain.
 	Bootstrapped() error
 
 	// Shutdown is called when the node is shutting down.

vms/avm/vm.go

@@ -68,6 +68,7 @@ type VM struct {
 	// State management
 	state *prefixedState
 
+	// Set to true once this VM is marked as `Bootstrapped` by the engine
 	bootstrapped bool
 
 	// Transaction issuing
@@ -200,7 +201,8 @@ func (vm *VM) Initialize(
 	return vm.db.Commit()
 }
 
-// Bootstrapping marks this VM as bootstrapping
+// Bootstrapping is called by the consensus engine when it starts bootstrapping
+// this chain
 func (vm *VM) Bootstrapping() error {
 	for _, fx := range vm.fxs {
 		if err := fx.Fx.Bootstrapping(); err != nil {
@@ -210,7 +212,8 @@ func (vm *VM) Bootstrapping() error {
 	return nil
 }
 
-// Bootstrapped marks this VM as bootstrapped
+// Bootstrapped is called by the consensus engine when it is done bootstrapping
+// this chain
 func (vm *VM) Bootstrapped() error {
 	for _, fx := range vm.fxs {
 		if err := fx.Fx.Bootstrapped(); err != nil {