1 files changed, 58 insertions, 0 deletions
diff --git a/roomserver/state/state_test.go b/roomserver/state/state_test.go
new file mode 100644
index 00000000..c5705678
--- /dev/null
+++ b/roomserver/state/state_test.go
@@ -0,0 +1,58 @@
+// Copyright 2017 Vector Creations Ltd
+// Copyright 2018 New Vector Ltd
+// Copyright 2019-2020 The Matrix.org Foundation C.I.C.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package state
+
+import (
+	"testing"
+
+	"github.com/matrix-org/dendrite/roomserver/types"
+)
+
+func TestFindDuplicateStateKeys(t *testing.T) {
+	testCases := []struct {
+		Input []types.StateEntry
+		Want  []types.StateEntry
+	}{{
+		Input: []types.StateEntry{
+			{StateKeyTuple: types.StateKeyTuple{EventTypeNID: 1, EventStateKeyNID: 1}, EventNID: 1},
+			{StateKeyTuple: types.StateKeyTuple{EventTypeNID: 1, EventStateKeyNID: 1}, EventNID: 2},
+			{StateKeyTuple: types.StateKeyTuple{EventTypeNID: 2, EventStateKeyNID: 2}, EventNID: 3},
+		},
+		Want: []types.StateEntry{
+			{StateKeyTuple: types.StateKeyTuple{EventTypeNID: 1, EventStateKeyNID: 1}, EventNID: 1},
+			{StateKeyTuple: types.StateKeyTuple{EventTypeNID: 1, EventStateKeyNID: 1}, EventNID: 2},
+		},
+	}, {
+		Input: []types.StateEntry{
+			{StateKeyTuple: types.StateKeyTuple{EventTypeNID: 1, EventStateKeyNID: 1}, EventNID: 1},
+			{StateKeyTuple: types.StateKeyTuple{EventTypeNID: 1, EventStateKeyNID: 2}, EventNID: 2},
+		},
+		Want: nil,
+	}}
+
+	for _, test := range testCases {
+		got := findDuplicateStateKeys(test.Input)
+		if len(got) != len(test.Want) {
+			t.Fatalf("Wanted %v, got %v", test.Want, got)
+		}
+		for i := range got {
+			if got[i] != test.Want[i] {
+				t.Fatalf("Wanted %v, got %v", test.Want, got)
+			}
+		}
+	}
+}