[bugfix] set link header lo,hi values directly from returned slice, don't account for filtering (#4421)

this fixes an issue with list pagination in list timelines as seen here: https://codeberg.org/tusky/Tusky/issues/5235

Reviewed-on: https://codeberg.org/superseriousbusiness/gotosocial/pulls/4421
Co-authored-by: kim <grufwub@gmail.com>
Co-committed-by: kim <grufwub@gmail.com>

internal/cache/timeline/status.go

@@ -387,10 +387,6 @@ func (t *StatusTimeline) Load(
 				return nil, "", "", gtserror.Newf("error loading statuses: %w", err)
 			}
 
-			// Set returned lo, hi values.
-			lo = metas[len(metas)-1].ID
-			hi = metas[0].ID
-
 			// Prepare frontend API models for
 			// the cached statuses. For now this
 			// also does its own extra filtering.
@@ -408,8 +404,8 @@ func (t *StatusTimeline) Load(
 	// we need to call to database.
 	if len(apiStatuses) < limit {
 
-		// Pass through to main timeline db load function.
+		// Pass to main timeline db load function.
-		apiStatuses, lo, hi, err = loadStatusTimeline(ctx,
+		apiStatuses, err = loadStatusTimeline(ctx,
 			nextPg,
 			metas,
 			apiStatuses,
@@ -422,6 +418,15 @@ func (t *StatusTimeline) Load(
 		}
 	}
 
+	// Reset values.
+	lo, hi = "", ""
+
+	if len(apiStatuses) > 0 {
+		// Set returned lo, hi paging values.
+		lo = apiStatuses[len(apiStatuses)-1].ID
+		hi = apiStatuses[0].ID
+	}
+
 	if order.Ascending() {
 		// The caller always expects the statuses
 		// to be returned in DESC order, but we
@@ -452,18 +457,12 @@ func loadStatusTimeline(
 	prepareAPI func(status *gtsmodel.Status) (apiStatus *apimodel.Status, err error),
 ) (
 	[]*apimodel.Status,
-	string, // lo
-	string, // hi
 	error,
 ) {
 	if loadPage == nil {
 		panic("nil load page func")
 	}
 
-	// Lowest and highest ID
-	// vals of loaded statuses.
-	var lo, hi string
-
 	// Extract paging params, in particular
 	// limit is used separate to nextPg to
 	// determine the *expected* return limit,
@@ -489,7 +488,7 @@ func loadStatusTimeline(
 		// Load next timeline statuses.
 		statuses, err := loadPage(nextPg)
 		if err != nil {
-			return nil, "", "", gtserror.Newf("error loading timeline: %w", err)
+			return nil, gtserror.Newf("error loading timeline: %w", err)
 		}
 
 		// No more statuses from
@@ -498,12 +497,6 @@ func loadStatusTimeline(
 			break
 		}
 
-		if hi == "" {
-			// Set hi returned paging
-			// value if not already set.
-			hi = statuses[0].ID
-		}
-
 		// Update nextPg cursor parameter for next database query.
 		nextPageParams(nextPg, statuses[len(statuses)-1].ID, order)
 
@@ -530,13 +523,7 @@ func loadStatusTimeline(
 		)
 	}
 
-	if len(apiStatuses) > 0 {
+	return apiStatuses, nil
-		// We finished loading statuses with
-		// values to return, set lo paging value.
-		lo = apiStatuses[len(apiStatuses)-1].ID
-	}
-
-	return apiStatuses, lo, hi, nil
 }
 
 // InsertOne allows you to insert a single status into the timeline, with optional prepared API model.
@@ -671,6 +658,9 @@ func (t *StatusTimeline) UnprepareByStatusIDs(statusIDs ...string) {
 // timeline entries authored by account ID, including boosts by account ID.
 func (t *StatusTimeline) UnprepareByAccountIDs(accountIDs ...string) {
 	keys := make([]structr.Key, len(accountIDs))
+	if len(keys) != len(accountIDs) {
+		panic(gtserror.New("BCE"))
+	}
 
 	// Nil check indices outside loops.
 	if t.idx_AccountID == nil ||

internal/processing/timeline/public_test.go

@@ -91,9 +91,9 @@ func (suite *PublicTestSuite) TestPublicTimelineGetNotEmpty() {
 	// some other statuses were filtered out.
 	suite.NoError(errWithCode)
 	suite.Len(resp.Items, 1)
-	suite.Equal(`<http://localhost:8080/api/v1/timelines/public?limit=1&local=false&max_id=01F8MHCP5P2NWYQ416SBA0XSEV>; rel="next", <http://localhost:8080/api/v1/timelines/public?limit=1&local=false&min_id=01FF25D5Q0DH7CHD57CTRS6WK0>; rel="prev"`, resp.LinkHeader)
+	suite.Equal("<http://localhost:8080/api/v1/timelines/public?limit=1&local=false&max_id=01F8MHCP5P2NWYQ416SBA0XSEV>; rel=\"next\", <http://localhost:8080/api/v1/timelines/public?limit=1&local=false&min_id=01F8MHCP5P2NWYQ416SBA0XSEV>; rel=\"prev\"", resp.LinkHeader)
-	suite.Equal(`http://localhost:8080/api/v1/timelines/public?limit=1&local=false&max_id=01F8MHCP5P2NWYQ416SBA0XSEV`, resp.NextLink)
+	suite.Equal("http://localhost:8080/api/v1/timelines/public?limit=1&local=false&max_id=01F8MHCP5P2NWYQ416SBA0XSEV", resp.NextLink)
-	suite.Equal(`http://localhost:8080/api/v1/timelines/public?limit=1&local=false&min_id=01FF25D5Q0DH7CHD57CTRS6WK0`, resp.PrevLink)
+	suite.Equal("http://localhost:8080/api/v1/timelines/public?limit=1&local=false&min_id=01F8MHCP5P2NWYQ416SBA0XSEV", resp.PrevLink)
 }
 
 // A timeline containing a status hidden due to filtering should return other statuses with no error.