From 87283e9de785f5153c5cf9b326d2640e202a36b3 Mon Sep 17 00:00:00 2001
From: Kegan Dougal <kegan@matrix.org>
Date: Fri, 6 Mar 2020 14:31:12 +0000
Subject: [PATCH] bugfix: fix sytest 155 by actually returning depth+1 and not
 0

---
 roomserver/storage/sqlite3/events_table.go | 10 ++++++----
 syncapi/routing/messages.go                |  4 ++++
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/roomserver/storage/sqlite3/events_table.go b/roomserver/storage/sqlite3/events_table.go
index 56e379100..4fa095913 100644
--- a/roomserver/storage/sqlite3/events_table.go
+++ b/roomserver/storage/sqlite3/events_table.go
@@ -111,7 +111,6 @@ type eventStatements struct {
 	bulkSelectEventReferenceStmt           *sql.Stmt
 	bulkSelectEventIDStmt                  *sql.Stmt
 	bulkSelectEventNIDStmt                 *sql.Stmt
-	selectMaxEventDepthStmt                *sql.Stmt
 }
 
 func (s *eventStatements) prepare(db *sql.DB) (err error) {
@@ -135,7 +134,6 @@ func (s *eventStatements) prepare(db *sql.DB) (err error) {
 		{&s.bulkSelectEventReferenceStmt, bulkSelectEventReferenceSQL},
 		{&s.bulkSelectEventIDStmt, bulkSelectEventIDSQL},
 		{&s.bulkSelectEventNIDStmt, bulkSelectEventNIDSQL},
-		{&s.selectMaxEventDepthStmt, selectMaxEventDepthSQL},
 	}.prepare(db)
 }
 
@@ -462,8 +460,12 @@ func (s *eventStatements) bulkSelectEventNID(ctx context.Context, txn *sql.Tx, e
 
 func (s *eventStatements) selectMaxEventDepth(ctx context.Context, txn *sql.Tx, eventNIDs []types.EventNID) (int64, error) {
 	var result int64
-	selectStmt := common.TxStmt(txn, s.selectMaxEventDepthStmt)
-	err := selectStmt.QueryRowContext(ctx, eventNIDsAsArray(eventNIDs)).Scan(&result)
+	iEventIDs := make([]interface{}, len(eventNIDs))
+	for i, v := range eventNIDs {
+		iEventIDs[i] = v
+	}
+	sqlStr := strings.Replace(selectMaxEventDepthSQL, "($1)", common.QueryVariadic(len(iEventIDs)), 1)
+	err := txn.QueryRowContext(ctx, sqlStr, iEventIDs...).Scan(&result)
 	if err != nil {
 		return 0, err
 	}
diff --git a/syncapi/routing/messages.go b/syncapi/routing/messages.go
index 7bbe16f3c..83bf75b2e 100644
--- a/syncapi/routing/messages.go
+++ b/syncapi/routing/messages.go
@@ -16,6 +16,7 @@ package routing
 
 import (
 	"context"
+	"fmt"
 	"net/http"
 	"sort"
 	"strconv"
@@ -176,6 +177,7 @@ func (r *messagesReq) retrieveEvents() (
 		r.ctx, r.from, r.to, r.roomID, r.limit, r.backwardOrdering,
 	)
 	if err != nil {
+		err = fmt.Errorf("GetEventsInRange: %s", err)
 		return
 	}
 
@@ -226,12 +228,14 @@ func (r *messagesReq) retrieveEvents() (
 		r.ctx, events[0].EventID(),
 	)
 	if err != nil {
+		err = fmt.Errorf("EventPositionInTopology: for start event %s: %s", events[0].EventID(), err)
 		return
 	}
 	endPos, err := r.db.EventPositionInTopology(
 		r.ctx, events[len(events)-1].EventID(),
 	)
 	if err != nil {
+		err = fmt.Errorf("EventPositionInTopology: for end event %s: %s", events[len(events)-1].EventID(), err)
 		return
 	}
 	// Generate pagination tokens to send to the client using the positions