preallocating memory when we can

.golangci.yml

@@ -25,7 +25,6 @@ linters:
     - scopelint
     - stylecheck
     - deadcode
-    - prealloc
 
 # linters-settings:
 #   govet:

crypto/merkle/proof.go

@@ -98,7 +98,7 @@ func (prt *ProofRuntime) Decode(pop ProofOp) (ProofOperator, error) {
 }
 
 func (prt *ProofRuntime) DecodeProof(proof *Proof) (ProofOperators, error) {
-	var poz ProofOperators
+	poz := make(ProofOperators, 0, len(proof.Ops))
 	for _, pop := range proof.Ops {
 		operator, err := prt.Decode(pop)
 		if err != nil {

libs/common/colors.go

@@ -43,7 +43,7 @@ func treat(s string, color string) string {
 }
 
 func treatAll(color string, args ...interface{}) string {
-	var parts []string
+	parts := make([]string, 0, len(args))
 	for _, arg := range args {
 		parts = append(parts, treat(fmt.Sprintf("%v", arg), color))
 	}

libs/events/events.go

@@ -188,7 +188,7 @@ func (cell *eventCell) RemoveListener(listenerID string) int {
 
 func (cell *eventCell) FireEvent(data EventData) {
 	cell.mtx.RLock()
-	var eventCallbacks []EventCallback
+	eventCallbacks := make([]EventCallback, 0, len(cell.listeners))
 	for _, cb := range cell.listeners {
 		eventCallbacks = append(eventCallbacks, cb)
 	}

p2p/pex/pex_reactor.go

@@ -616,10 +616,9 @@ func (of oldestFirst) Less(i, j int) bool { return of[i].LastAttempt.Before(of[j
 // getPeersToCrawl returns addresses of potential peers that we wish to validate.
 // NOTE: The status information is ordered as described above.
 func (r *PEXReactor) getPeersToCrawl() []crawlPeerInfo {
-	var of oldestFirst
-
 	// TODO: be more selective
 	addrs := r.book.ListOfKnownAddresses()
+	of := make(oldestFirst, 0, len(addrs))
 	for _, addr := range addrs {
 		if len(addr.ID()) == 0 {
 			continue // dont use peers without id