From b9754f45918ef0bed5b4f24b41bd83fa6c9654fc Mon Sep 17 00:00:00 2001
From: Till Faelligen <2353100+S7evinK@users.noreply.github.com>
Date: Mon, 16 Jan 2023 13:39:20 +0100
Subject: [PATCH] Test StreamToTopologicalPosition

---
 syncapi/storage/storage_test.go | 82 +++++++++++++++++++++++++++++++++
 1 file changed, 82 insertions(+)

diff --git a/syncapi/storage/storage_test.go b/syncapi/storage/storage_test.go
index 5c31313ec..e65367d8b 100644
--- a/syncapi/storage/storage_test.go
+++ b/syncapi/storage/storage_test.go
@@ -217,6 +217,88 @@ func TestGetEventsInRangeWithTopologyToken(t *testing.T) {
 	})
 }
 
+func TestStreamToTopologicalPosition(t *testing.T) {
+	alice := test.NewUser(t)
+	r := test.NewRoom(t, alice)
+
+	testCases := []struct {
+		name             string
+		roomID           string
+		streamPos        types.StreamPosition
+		backwardOrdering bool
+		wantToken        types.TopologyToken
+	}{
+		{
+			name:             "forward ordering found streamPos returns found position",
+			roomID:           r.ID,
+			streamPos:        1,
+			backwardOrdering: false,
+			wantToken:        types.TopologyToken{Depth: 1, PDUPosition: 1},
+		},
+		{
+			name:             "forward ordering not found streamPos returns max position",
+			roomID:           r.ID,
+			streamPos:        100,
+			backwardOrdering: false,
+			wantToken:        types.TopologyToken{Depth: math.MaxInt64, PDUPosition: math.MaxInt64},
+		},
+		{
+			name:             "backward ordering found streamPos returns found position",
+			roomID:           r.ID,
+			streamPos:        1,
+			backwardOrdering: true,
+			wantToken:        types.TopologyToken{Depth: 1, PDUPosition: 1},
+		},
+		{
+			name:             "backward ordering not found streamPos returns maxDepth with param pduPosition",
+			roomID:           r.ID,
+			streamPos:        100,
+			backwardOrdering: true,
+			wantToken:        types.TopologyToken{Depth: 5, PDUPosition: 100},
+		},
+		{
+			name:             "backward non-existent room returns zero token",
+			roomID:           "!doesnotexist:localhost",
+			streamPos:        1,
+			backwardOrdering: true,
+			wantToken:        types.TopologyToken{Depth: 0, PDUPosition: 1},
+		},
+		{
+			name:             "forward non-existent room returns max token",
+			roomID:           "!doesnotexist:localhost",
+			streamPos:        1,
+			backwardOrdering: false,
+			wantToken:        types.TopologyToken{Depth: math.MaxInt64, PDUPosition: math.MaxInt64},
+		},
+	}
+
+	test.WithAllDatabases(t, func(t *testing.T, dbType test.DBType) {
+		db, close, closeBase := MustCreateDatabase(t, dbType)
+		defer close()
+		defer closeBase()
+
+		txn, err := db.NewDatabaseTransaction(ctx)
+		if err != nil {
+			t.Fatal(err)
+		}
+		defer txn.Rollback()
+		MustWriteEvents(t, db, r.Events())
+
+		for _, tc := range testCases {
+			t.Run(tc.name, func(t *testing.T) {
+				token, err := txn.StreamToTopologicalPosition(ctx, tc.roomID, tc.streamPos, tc.backwardOrdering)
+				if err != nil {
+					t.Fatal(err)
+				}
+				if tc.wantToken != token {
+					t.Fatalf("expected token %q, got %q", tc.wantToken, token)
+				}
+			})
+		}
+
+	})
+}
+
 /*
 // The purpose of this test is to make sure that backpagination returns all events, even if some events have the same depth.
 // For cases where events have the same depth, the streaming token should be used to tie break so events written via WriteEvent