Try fixing your unit tests

models/issues/issue_project.go

@@ -62,7 +62,7 @@ func LoadProjectIssueColumnMap(ctx context.Context, projectID, defaultColumnID i
 func LoadIssuesFromColumn(ctx context.Context, b *project_model.Column, opts *IssuesOptions) (IssueList, error) {
 	issueList, err := Issues(ctx, opts.Copy(func(o *IssuesOptions) {
 		o.ProjectColumnID = b.ID
-		o.ProjectID = b.ProjectID
+		o.ProjectIDs = []int64{b.ProjectID}
 		o.SortType = "project-column-sorting"
 	}))
 	if err != nil {
@@ -72,7 +72,7 @@ func LoadIssuesFromColumn(ctx context.Context, b *project_model.Column, opts *Is
 	if b.Default {
 		issues, err := Issues(ctx, opts.Copy(func(o *IssuesOptions) {
 			o.ProjectColumnID = db.NoConditionID
-			o.ProjectID = b.ProjectID
+			o.ProjectIDs = []int64{b.ProjectID}
 			o.SortType = "project-column-sorting"
 		}))
 		if err != nil {

models/issues/issue_search.go

@@ -36,7 +36,7 @@ type IssuesOptions struct { //nolint
 	ReviewedID         int64
 	SubscriberID       int64
 	MilestoneIDs       []int64
-	ProjectID          int64
+	ProjectIDs         []int64
 	ProjectColumnID    int64
 	IsClosed           optional.Option[bool]
 	IsPull             optional.Option[bool]
@@ -196,11 +196,17 @@ func applyMilestoneCondition(sess *xorm.Session, opts *IssuesOptions) {
 }
 
 func applyProjectCondition(sess *xorm.Session, opts *IssuesOptions) {
-	if opts.ProjectID > 0 { // specific project
+	if len(opts.ProjectIDs) > 0 { // specific project
+		var includedProjectIDs []int64
+		for _, projectID := range opts.ProjectIDs {
+			if projectID > 0 {
+				includedProjectIDs = append(includedProjectIDs, projectID)
+			}
+		}
+		if len(includedProjectIDs) > 0 {
 			sess.Join("INNER", "project_issue", "issue.id = project_issue.issue_id").
-			And("project_issue.project_id=?", opts.ProjectID)
+				In("project_issue.project_id", includedProjectIDs)
-	} else if opts.ProjectID == db.NoConditionID { // show those that are in no project
+		}
-		sess.And(builder.NotIn("issue.id", builder.Select("issue_id").From("project_issue").And(builder.Neq{"project_id": 0})))
 	}
 	// opts.ProjectID == 0 means all projects,
 	// do not need to apply any condition

modules/indexer/issues/bleve/bleve.go

@@ -241,9 +241,14 @@ func (b *Indexer) Search(ctx context.Context, options *internal.SearchOptions) (
 		queries = append(queries, bleve.NewDisjunctionQuery(milestoneQueries...))
 	}
 
-	if options.ProjectID.Has() {
+	if len(options.ProjectIDs) > 0 {
-		queries = append(queries, inner_bleve.NumericEqualityQuery(options.ProjectID.Value(), "project_id"))
+		var projectQueries []query.Query
+		for _, projectID := range options.ProjectIDs {
+			projectQueries = append(projectQueries, inner_bleve.NumericEqualityQuery(projectID, "project_id"))
 		}
+		queries = append(queries, bleve.NewDisjunctionQuery(projectQueries...))
+	}
+
 	if options.ProjectColumnID.Has() {
 		queries = append(queries, inner_bleve.NumericEqualityQuery(options.ProjectColumnID.Value(), "project_board_id"))
 	}

modules/indexer/issues/db/options.go

@@ -65,7 +65,6 @@ func ToDBOptions(ctx context.Context, options *internal.SearchOptions) (*issue_m
 		ReviewRequestedID:  convertID(options.ReviewRequestedID),
 		ReviewedID:         convertID(options.ReviewedID),
 		SubscriberID:       convertID(options.SubscriberID),
-		ProjectID:          convertID(options.ProjectID),
 		ProjectColumnID:    convertID(options.ProjectColumnID),
 		IsClosed:           options.IsClosed,
 		IsPull:             options.IsPull,
@@ -88,6 +87,10 @@ func ToDBOptions(ctx context.Context, options *internal.SearchOptions) (*issue_m
 		opts.MilestoneIDs = options.MilestoneIDs
 	}
 
+	if len(options.ProjectIDs) > 0 {
+		opts.ProjectIDs = options.ProjectIDs
+	}
+
 	if options.NoLabelOnly {
 		opts.LabelIDs = []int64{0} // Be careful, it's zero, not db.NoConditionID
 	} else {

modules/indexer/issues/dboptions.go

@@ -46,10 +46,8 @@ func ToSearchOptions(keyword string, opts *issues_model.IssuesOptions) *SearchOp
 		searchOpt.MilestoneIDs = opts.MilestoneIDs
 	}
 
-	if opts.ProjectID > 0 {
+	if len(opts.ProjectIDs) > 0 {
-		searchOpt.ProjectID = optional.Some(opts.ProjectID)
+		searchOpt.ProjectIDs = opts.ProjectIDs
-	} else if opts.ProjectID == db.NoConditionID { // FIXME: this is inconsistent from other places
-		searchOpt.ProjectID = optional.Some[int64](0) // Those issues with no project(projectid==0)
 	}
 
 	searchOpt.AssigneeID = opts.AssigneeID

modules/indexer/issues/elasticsearch/elasticsearch.go

@@ -204,8 +204,8 @@ func (b *Indexer) Search(ctx context.Context, options *internal.SearchOptions) (
 		query.Must(elastic.NewTermsQuery("milestone_id", toAnySlice(options.MilestoneIDs)...))
 	}
 
-	if options.ProjectID.Has() {
+	if len(options.ProjectIDs) > 0 {
-		query.Must(elastic.NewTermQuery("project_id", options.ProjectID.Value()))
+		query.Must(elastic.NewTermsQuery("project_id", toAnySlice(options.ProjectIDs)...))
 	}
 	if options.ProjectColumnID.Has() {
 		query.Must(elastic.NewTermQuery("project_board_id", options.ProjectColumnID.Value()))

modules/indexer/issues/internal/model.go

@@ -94,7 +94,7 @@ type SearchOptions struct {
 
 	MilestoneIDs []int64 // milestones the issues have
 
-	ProjectID       optional.Option[int64] // project the issues belong to
+	ProjectIDs      []int64                // project the issues belong to
 	ProjectColumnID optional.Option[int64] // project column the issues belong to
 
 	PosterID   string // poster of the issues, "(none)" or "(any)" or a user ID

modules/indexer/issues/internal/tests/tests.go

@@ -307,7 +307,7 @@ var cases = []*testIndexerCase{
 			Paginator: &db.ListOptions{
 				PageSize: 5,
 			},
-			ProjectID: optional.Some(int64(1)),
+			ProjectIDs: []int64{1},
 		},
 		Expected: func(t *testing.T, data map[int64]*internal.IndexerData, result *internal.SearchResult) {
 			assert.Len(t, result.Hits, 5)
@@ -325,7 +325,7 @@ var cases = []*testIndexerCase{
 			Paginator: &db.ListOptions{
 				PageSize: 5,
 			},
-			ProjectID: optional.Some(int64(0)),
+			ProjectIDs: []int64{0},
 		},
 		Expected: func(t *testing.T, data map[int64]*internal.IndexerData, result *internal.SearchResult) {
 			assert.Len(t, result.Hits, 5)

modules/indexer/issues/meilisearch/meilisearch.go

@@ -180,8 +180,8 @@ func (b *Indexer) Search(ctx context.Context, options *internal.SearchOptions) (
 		query.And(inner_meilisearch.NewFilterIn("milestone_id", options.MilestoneIDs...))
 	}
 
-	if options.ProjectID.Has() {
+	if len(options.ProjectIDs) > 0 {
-		query.And(inner_meilisearch.NewFilterEq("project_id", options.ProjectID.Value()))
+		query.And(inner_meilisearch.NewFilterIn("project_id", options.ProjectIDs...))
 	}
 	if options.ProjectColumnID.Has() {
 		query.And(inner_meilisearch.NewFilterEq("project_board_id", options.ProjectColumnID.Value()))

routers/web/repo/issue_list.go

@@ -189,7 +189,7 @@ func SearchIssues(ctx *context.Context) {
 		IsClosed:            isClosed,
 		IncludedAnyLabelIDs: includedAnyLabels,
 		MilestoneIDs:        includedMilestones,
-		ProjectID:           projectID,
+		ProjectIDs:          projectID,
 		SortBy:              issue_indexer.SortByCreatedDesc,
 	}
 
@@ -349,7 +349,7 @@ func SearchRepoIssuesJSON(ctx *context.Context) {
 		RepoIDs:    []int64{ctx.Repo.Repository.ID},
 		IsPull:     isPull,
 		IsClosed:   isClosed,
-		ProjectID: projectID,
+		ProjectIDs: projectID,
 		SortBy:     issue_indexer.SortByCreatedDesc,
 	}
 	if since != 0 {
@@ -542,7 +542,7 @@ func prepareIssueFilterAndList(ctx *context.Context, milestoneID, projectID int6
 		RepoIDs:           []int64{repo.ID},
 		LabelIDs:          preparedLabelFilter.SelectedLabelIDs,
 		MilestoneIDs:      mileIDs,
-		ProjectID:         projectID,
+		ProjectIDs:        []int64{projectID},
 		AssigneeID:        assigneeID,
 		MentionedID:       mentionedID,
 		PosterID:          posterUserID,
@@ -629,7 +629,7 @@ func prepareIssueFilterAndList(ctx *context.Context, milestoneID, projectID int6
 			ReviewRequestedID: reviewRequestedID,
 			ReviewedID:        reviewedID,
 			MilestoneIDs:      mileIDs,
-			ProjectID:         projectID,
+			ProjectIDs:        []int64{projectID},
 			IsClosed:          isShowClosed,
 			IsPull:            isPullOption,
 			LabelIDs:          preparedLabelFilter.SelectedLabelIDs,

services/projects/issue.go

@@ -89,7 +89,7 @@ func MoveIssuesOnProjectColumn(ctx context.Context, doer *user_model.User, colum
 // LoadIssuesFromProject load issues assigned to each project column inside the given project
 func LoadIssuesFromProject(ctx context.Context, project *project_model.Project, opts *issues_model.IssuesOptions) (map[int64]issues_model.IssueList, error) {
 	issueList, err := issues_model.Issues(ctx, opts.Copy(func(o *issues_model.IssuesOptions) {
-		o.ProjectID = project.ID
+		o.ProjectIDs = []int64{project.ID}
 		o.SortType = "project-column-sorting"
 	}))
 	if err != nil {
@@ -180,7 +180,7 @@ func LoadIssueNumbersForProject(ctx context.Context, project *project_model.Proj
 
 	// for user or org projects, we need to check access permissions
 	opts := issues_model.IssuesOptions{
-		ProjectID: project.ID,
+		ProjectIDs: []int64{project.ID},
 		Doer:       doer,
 		AllPublic:  doer == nil,
 		Owner:      project.Owner,