Add ReceiverSelectorTest

core/src/test/java/bisq/core/util/FeeReceiverSelectorTest.java

@@ -0,0 +1,107 @@
+/*
+ * This file is part of Bisq.
+ *
+ * Bisq is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or (at
+ * your option) any later version.
+ *
+ * Bisq is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public
+ * License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with Bisq. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package bisq.core.util;
+
+import bisq.core.dao.DaoFacade;
+import bisq.core.dao.governance.param.Param;
+import bisq.core.filter.Filter;
+import bisq.core.filter.FilterManager;
+
+import com.google.common.primitives.Longs;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Random;
+
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import static org.junit.Assert.assertEquals;
+import static org.mockito.Mockito.when;
+
+@RunWith(MockitoJUnitRunner.class)
+public class FeeReceiverSelectorTest {
+    @Mock
+    private DaoFacade daoFacade;
+    @Mock
+    private FilterManager filterManager;
+
+    @Test
+    public void testGetAddress() {
+        Random rnd = new Random(123);
+        when(filterManager.getFilter()).thenReturn(filterWithReceivers(
+                List.of("", "foo#0.001", "ill-formed", "bar#0.002", "baz#0.001", "partial#bad")));
+
+        Map<String, Integer> selectionCounts = new HashMap<>();
+        for (int i = 0; i < 400; i++) {
+            String address = FeeReceiverSelector.getAddress(daoFacade, filterManager, rnd);
+            selectionCounts.compute(address, (k, n) -> n != null ? n + 1 : 1);
+        }
+
+        assertEquals(3, selectionCounts.size());
+
+        // Check within 2 std. of the expected values (95% confidence each):
+        assertEquals(100.0, selectionCounts.get("foo"), 18);
+        assertEquals(200.0, selectionCounts.get("bar"), 20);
+        assertEquals(100.0, selectionCounts.get("baz"), 18);
+    }
+
+    @Test
+    public void testGetAddress_noValidReceivers() {
+        when(daoFacade.getParamValue(Param.RECIPIENT_BTC_ADDRESS)).thenReturn("default");
+
+        when(filterManager.getFilter()).thenReturn(null);
+        assertEquals("default", FeeReceiverSelector.getAddress(daoFacade, filterManager));
+
+        when(filterManager.getFilter()).thenReturn(filterWithReceivers(null));
+        assertEquals("default", FeeReceiverSelector.getAddress(daoFacade, filterManager));
+
+        when(filterManager.getFilter()).thenReturn(filterWithReceivers(List.of()));
+        assertEquals("default", FeeReceiverSelector.getAddress(daoFacade, filterManager));
+
+        when(filterManager.getFilter()).thenReturn(filterWithReceivers(List.of("ill-formed")));
+        assertEquals("default", FeeReceiverSelector.getAddress(daoFacade, filterManager));
+    }
+
+    @Test
+    public void testWeightedSelection() {
+        Random rnd = new Random(456);
+
+        int[] selections = new int[3];
+        for (int i = 0; i < 6000; i++) {
+            selections[FeeReceiverSelector.weightedSelection(Longs.asList(1, 2, 3), rnd)]++;
+        }
+
+        // Check within 2 std. of the expected values (95% confidence each):
+        assertEquals(1000.0, selections[0], 58);
+        assertEquals(2000.0, selections[1], 74);
+        assertEquals(3000.0, selections[2], 78);
+    }
+
+    private static Filter filterWithReceivers(List<String> btcFeeReceiverAddresses) {
+        return new Filter(null, null, null, null,
+                null, null, null, null,
+                false, null, false, null,
+                null, null, null, null,
+                btcFeeReceiverAddresses);
+    }
+}