fix(api)!: list only open pull requests when no state is given (#40078)

`GET /repos/{owner}/{repo}/pulls` is documented with `state` defaulting
to `open`, but without `state` it returned every pull request, closed
and merged ones included. Now it parses `state` with
`ParseIssueFilterStateIsClosed`, like the issues and milestones
endpoints, so no state means open, as documented. `closed` and `all`
work as before. GitHub's pulls endpoint also defaults to open.

models/issues/pull_list.go

@@ -14,6 +14,7 @@ import (
 	user_model "gitea.dev/models/user"
 	"gitea.dev/modules/container"
 	"gitea.dev/modules/log"
+	"gitea.dev/modules/optional"
 	"gitea.dev/modules/timeutil"
 	"gitea.dev/modules/util"
 
@@ -23,7 +24,7 @@ import (
 // PullRequestsOptions holds the options for PRs
 type PullRequestsOptions struct {
 	db.ListOptions
-	State       string
+	IsClosed    optional.Option[bool]
 	SortType    string
 	Labels      []int64
 	MilestoneID int64
@@ -39,9 +40,8 @@ func listPullRequestStatement(ctx context.Context, baseRepoID int64, opts *PullR
 	}
 
 	sess.Join("INNER", "issue", "pull_request.issue_id = issue.id")
-	switch opts.State {
-	case "closed", "open":
-		sess.And("issue.is_closed=?", opts.State == "closed")
+	if opts.IsClosed.Has() {
+		sess.And("issue.is_closed=?", opts.IsClosed.Value())
 	}
 
 	if len(opts.Labels) > 0 {

models/issues/pull_test.go

@@ -13,6 +13,7 @@ import (
 	repo_model "gitea.dev/models/repo"
 	"gitea.dev/models/unittest"
 	user_model "gitea.dev/models/user"
+	"gitea.dev/modules/optional"
 	"gitea.dev/modules/setting"
 
 	"github.com/stretchr/testify/assert"
@@ -92,7 +93,7 @@ func testPullRequestsNewest(t *testing.T) {
 		ListOptions: db.ListOptions{
 			Page: 1,
 		},
-		State:    "open",
+		IsClosed: optional.Some(false),
 		SortType: "newest",
 	})
 	assert.NoError(t, err)
@@ -130,7 +131,7 @@ func testPullRequestsClosedRecentSortType(t *testing.T) {
 				ListOptions: db.ListOptions{
 					Page: 1,
 				},
-				State:    "closed",
+				IsClosed: optional.Some(true),
 				SortType: test.sortType,
 			})
 			require.NoError(t, err)
@@ -175,7 +176,7 @@ func testPullRequestsOldest(t *testing.T) {
 		ListOptions: db.ListOptions{
 			Page: 1,
 		},
-		State:    "open",
+		IsClosed: optional.Some(false),
 		SortType: "oldest",
 	})
 	assert.NoError(t, err)

routers/api/v1/repo/pull.go

@@ -131,7 +131,7 @@ func ListPullRequests(ctx *context.APIContext) {
 	listOptions := utils.GetListOptions(ctx)
 	prs, maxResults, err := issues_model.PullRequests(ctx, ctx.Repo.Repository.ID, &issues_model.PullRequestsOptions{
 		ListOptions: listOptions,
-		State:       ctx.FormTrim("state"),
+		IsClosed:    common.ParseIssueFilterStateIsClosed(ctx.FormTrim("state")),
 		SortType:    ctx.FormTrim("sort"),
 		Labels:      labelIDs,
 		MilestoneID: ctx.FormInt64("milestone"),

tests/integration/api_pull_test.go

@@ -144,6 +144,28 @@ func TestAPIViewPulls(t *testing.T) {
 			}))
 	}
 
+	t.Run("DefaultState", func(t *testing.T) {
+		writeToken := getTokenForLoggedInUser(t, ctx.Session, auth_model.AccessTokenScopeWriteRepository)
+		req := NewRequestWithJSON(t, http.MethodPatch, fmt.Sprintf("/api/v1/repos/%s/%s/pulls/3", owner.Name, repo.Name), &api.EditPullRequestOption{
+			State: new(string(api.StateClosed)),
+		}).AddTokenAuth(writeToken)
+		MakeRequest(t, req, http.StatusCreated)
+
+		for query, want := range map[string][]int64{
+			"":             {2, 5},
+			"state=closed": {3},
+			"state=all":    {2, 3, 5},
+		} {
+			req := NewRequestf(t, "GET", "/api/v1/repos/%s/%s/pulls?%s", owner.Name, repo.Name, query).AddTokenAuth(ctx.Token)
+			listed := DecodeJSON(t, ctx.Session.MakeRequest(t, req, http.StatusOK), []*api.PullRequest{})
+			indexes := make([]int64, 0, len(listed))
+			for _, pr := range listed {
+				indexes = append(indexes, pr.Index)
+			}
+			assert.ElementsMatch(t, want, indexes, query)
+		}
+	})
+
 	t.Run("APIViewPullsByBaseHead", func(t *testing.T) {
 		req := NewRequestf(t, "GET", "/api/v1/repos/%s/%s/pulls/master/branch2", owner.Name, repo.Name).
 			AddTokenAuth(ctx.Token)