lnd: fix golint warning which requires to add additional comments

channeldb/error.go

@@ -3,31 +3,74 @@ package channeldb
 import "fmt"
 
 var (
-	ErrNoChanDBExists    = fmt.Errorf("channel db has not yet been created")
+	// ErrNoChanDBExists is returned when a channel bucket hasn't been
+	// created.
+	ErrNoChanDBExists = fmt.Errorf("channel db has not yet been created")
+
+	// ErrLinkNodesNotFound is returned when node info bucket hasn't been
+	// created.
 	ErrLinkNodesNotFound = fmt.Errorf("no link nodes exist")
 
+	// ErrNoActiveChannels  is returned when there is no active (open)
+	// channels within the database.
 	ErrNoActiveChannels = fmt.Errorf("no active channels exist")
-	ErrChannelNoExist   = fmt.Errorf("this channel does not exist")
-	ErrNoPastDeltas     = fmt.Errorf("channel has no recorded deltas")
 
-	ErrInvoiceNotFound   = fmt.Errorf("unable to locate invoice")
+	// ErrNoPastDeltas is returned when the channel delta bucket hasn't been
+	// created.
+	ErrNoPastDeltas = fmt.Errorf("channel has no recorded deltas")
+
+	// ErrInvoiceNotFound is returned when a targeted invoice can't be
+	// found.
+	ErrInvoiceNotFound = fmt.Errorf("unable to locate invoice")
+
+	// ErrNoInvoicesCreated is returned when we don't have invoices in
+	// our database to return.
 	ErrNoInvoicesCreated = fmt.Errorf("there are no existing invoices")
-	ErrDuplicateInvoice  = fmt.Errorf("invoice with payment hash already exists")
 
+	// ErrDuplicateInvoice is returned when an invoice with the target
+	// payment hash already exists.
+	ErrDuplicateInvoice = fmt.Errorf("invoice with payment hash already exists")
+
+	// ErrNoPaymentsCreated is returned when bucket of payments hasn't been
+	// created.
 	ErrNoPaymentsCreated = fmt.Errorf("there are no existing payments")
 
+	// ErrNodeNotFound is returned when node bucket exists, but node with
+	// specific identity can't be found.
 	ErrNodeNotFound = fmt.Errorf("link node with target identity not found")
+
+	// ErrMetaNotFound is returned when meta bucket hasn't been
+	// created.
 	ErrMetaNotFound = fmt.Errorf("unable to locate meta information")
 
-	ErrGraphNotFound      = fmt.Errorf("graph bucket not initialized")
-	ErrGraphNodesNotFound = fmt.Errorf("no graph nodes exist")
-	ErrGraphNoEdgesFound  = fmt.Errorf("no graph edges exist")
-	ErrGraphNodeNotFound  = fmt.Errorf("unable to find node")
-	ErrGraphNeverPruned   = fmt.Errorf("graph never pruned")
+	// ErrGraphNotFound is returned when at least one of the components of
+	// graph doesn't exist.
+	ErrGraphNotFound = fmt.Errorf("graph bucket not initialized")
 
+	// ErrGraphNeverPruned is returned when graph was never pruned.
+	ErrGraphNeverPruned = fmt.Errorf("graph never pruned")
+
+	// ErrSourceNodeNotSet is returned if the the source node of the graph
+	// hasn't been added The source node is the center node within a
+	// star-graph.
+	ErrSourceNodeNotSet = fmt.Errorf("source node does not exist")
+
+	// ErrGraphNodesNotFound is returned in case none of the nodes has
+	// been added in graph node bucket.
+	ErrGraphNodesNotFound = fmt.Errorf("no graph nodes exist")
+
+	// ErrGraphNoEdgesFound is returned in case of none of the channel/edges
+	// has been added in graph edge bucket.
+	ErrGraphNoEdgesFound = fmt.Errorf("no graph edges exist")
+
+	// ErrGraphNodeNotFound is returned when we're unable to find the target
+	// node.
+	ErrGraphNodeNotFound = fmt.Errorf("unable to find node")
+
+	// ErrEdgeNotFound is returned when an edge for the target chanID
+	// can't be found.
 	ErrEdgeNotFound = fmt.Errorf("edge for chanID not found")
 
+	// ErrNodeAliasNotFound is returned when alias for node can't be found.
 	ErrNodeAliasNotFound = fmt.Errorf("alias for node not found")
-
-	ErrSourceNodeNotSet = fmt.Errorf("source node does not exist")
 )