some refactor about code comments(#20821) (#22707)

fix #22691
backport #20821

Co-authored-by: zeripath <art27@cantab.net>

models/db/list_options.go

@@ -5,8 +5,11 @@
 package db
 
 import (
+	"context"
+
 	"code.gitea.io/gitea/modules/setting"
 
+	"xorm.io/builder"
 	"xorm.io/xorm"
 )
 
@@ -19,6 +22,7 @@ const (
 type Paginator interface {
 	GetSkipTake() (skip, take int)
 	GetStartEnd() (start, end int)
+	IsListAll() bool
 }
 
 // GetPaginatedSession creates a paginated database session
@@ -45,9 +49,12 @@ func SetEnginePagination(e Engine, p Paginator) Engine {
 // ListOptions options to paginate results
 type ListOptions struct {
 	PageSize int
-	Page     int // start from 1
+	Page     int  // start from 1
+	ListAll  bool // if true, then PageSize and Page will not be taken
 }
 
+var _ Paginator = &ListOptions{}
+
 // GetSkipTake returns the skip and take values
 func (opts *ListOptions) GetSkipTake() (skip, take int) {
 	opts.SetDefaultValues()
@@ -61,6 +68,11 @@ func (opts *ListOptions) GetStartEnd() (start, end int) {
 	return start, end
 }
 
+// IsListAll indicates PageSize and Page will be ignored
+func (opts *ListOptions) IsListAll() bool {
+	return opts.ListAll
+}
+
 // SetDefaultValues sets default values
 func (opts *ListOptions) SetDefaultValues() {
 	if opts.PageSize <= 0 {
@@ -80,6 +92,8 @@ type AbsoluteListOptions struct {
 	take int
 }
 
+var _ Paginator = &AbsoluteListOptions{}
+
 // NewAbsoluteListOptions creates a list option with applied limits
 func NewAbsoluteListOptions(skip, take int) *AbsoluteListOptions {
 	if skip < 0 {
@@ -94,6 +108,11 @@ func NewAbsoluteListOptions(skip, take int) *AbsoluteListOptions {
 	return &AbsoluteListOptions{skip, take}
 }
 
+// IsListAll will always return false
+func (opts *AbsoluteListOptions) IsListAll() bool {
+	return false
+}
+
 // GetSkipTake returns the skip and take values
 func (opts *AbsoluteListOptions) GetSkipTake() (skip, take int) {
 	return opts.skip, opts.take
@@ -103,3 +122,32 @@ func (opts *AbsoluteListOptions) GetSkipTake() (skip, take int) {
 func (opts *AbsoluteListOptions) GetStartEnd() (start, end int) {
 	return opts.skip, opts.skip + opts.take
 }
+
+// FindOptions represents a find options
+type FindOptions interface {
+	Paginator
+	ToConds() builder.Cond
+}
+
+// Find represents a common find function which accept an options interface
+func Find[T any](ctx context.Context, opts FindOptions, objects *[]T) error {
+	sess := GetEngine(ctx).Where(opts.ToConds())
+	if !opts.IsListAll() {
+		sess.Limit(opts.GetSkipTake())
+	}
+	return sess.Find(&objects)
+}
+
+// Count represents a common count function which accept an options interface
+func Count[T any](ctx context.Context, opts FindOptions, object T) (int64, error) {
+	return GetEngine(ctx).Where(opts.ToConds()).Count(object)
+}
+
+// FindAndCount represents a common findandcount function which accept an options interface
+func FindAndCount[T any](ctx context.Context, opts FindOptions, objects *[]T) (int64, error) {
+	sess := GetEngine(ctx).Where(opts.ToConds())
+	if !opts.IsListAll() {
+		sess.Limit(opts.GetSkipTake())
+	}
+	return sess.FindAndCount(&objects)
+}