chore: Preallocate space for slices with known size (#575)

Signed-off-by: satoru <[email protected]>

Author: suzaku

pkg/registry/endpoints.go

@@ -247,9 +247,9 @@ func SetRegistryEndpointCredentials(prefix, credentials string) error {
 
 // ConfiguredEndpoints returns a list of prefixes that are configured
 func ConfiguredEndpoints() []string {
-	r := []string{}
 	registryLock.RLock()
 	defer registryLock.RUnlock()
+	r := make([]string, 0, len(registries))
 	for _, v := range registries {
 		r = append(r, v.RegistryPrefix)
 	}

pkg/tag/tag.go

@@ -124,7 +124,7 @@ func (il ImageTagList) Add(tag *ImageTag) {
 
 // SortByName returns an array of ImageTag objects, sorted by the tag's name
 func (il ImageTagList) SortAlphabetically() SortableImageTagList {
-	sil := SortableImageTagList{}
+	sil := make(SortableImageTagList, 0, len(il.items))
 	for _, v := range il.items {
 		sil = append(sil, v)
 	}
@@ -136,7 +136,7 @@ func (il ImageTagList) SortAlphabetically() SortableImageTagList {
 
 // SortByDate returns a SortableImageTagList, sorted by the tag's date
 func (il ImageTagList) SortByDate() SortableImageTagList {
-	sil := SortableImageTagList{}
+	sil := make(SortableImageTagList, 0, len(il.items))
 	for _, v := range il.items {
 		sil = append(sil, v)
 	}