Performance improvements for pull request list page (#29900)

This PR will avoid load pullrequest.Issue twice in pull request list
page. It will reduce x times database queries for those WIP pull
requests.

Partially fix #29585

---------

Co-authored-by: Giteabot <teabot@gitea.io>

1 files changed, 10 insertions, 1 deletions

diff --git a/modules/util/slice.go b/modules/util/slice.go
index f00e84bf06..9c878c24be 100644
--- a/modules/util/slice.go
+++ b/modules/util/slice.go
@@ -54,7 +54,7 @@ func Sorted[S ~[]E, E cmp.Ordered](values S) S {
 	return values
 }
 
-// TODO: Replace with "maps.Values" once available
+// TODO: Replace with "maps.Values" once available, current it only in golang.org/x/exp/maps but not in standard library
 func ValuesOfMap[K comparable, V any](m map[K]V) []V {
 	values := make([]V, 0, len(m))
 	for _, v := range m {
@@ -62,3 +62,12 @@ func ValuesOfMap[K comparable, V any](m map[K]V) []V {
 	}
 	return values
 }
+
+// TODO: Replace with "maps.Keys" once available, current it only in golang.org/x/exp/maps but not in standard library
+func KeysOfMap[K comparable, V any](m map[K]V) []K {
+	keys := make([]K, 0, len(m))
+	for k := range m {
+		keys = append(keys, k)
+	}
+	return keys
+}