Add server-free plugin behavior tests

src/test/java/com/majinnaibu/bukkitplugins/metropolis/CurrentHomesStoreTest.java

@@ -0,0 +1,41 @@
+package com.majinnaibu.bukkitplugins.metropolis;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.io.File;
+import java.util.Map;
+import java.util.UUID;
+
+import org.bukkit.configuration.file.YamlConfiguration;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+class CurrentHomesStoreTest {
+	@TempDir
+	File temporaryDirectory;
+
+	@Test
+	void roundTripsHomesByUuid() throws Exception {
+		File file = new File(temporaryDirectory, "currentHomes.yml");
+		UUID playerId = UUID.fromString("123e4567-e89b-12d3-a456-426614174000");
+		Map<UUID, Integer> expected = Map.of(playerId, 3);
+
+		CurrentHomesStore.save(file, expected);
+
+		assertEquals(expected, CurrentHomesStore.load(file, ignored -> null));
+	}
+
+	@Test
+	void resolvesLegacyPlayerNameKeys() throws Exception {
+		File file = new File(temporaryDirectory, "currentHomes.yml");
+		UUID playerId = UUID.fromString("123e4567-e89b-12d3-a456-426614174000");
+		YamlConfiguration yaml = new YamlConfiguration();
+		yaml.set("OldPlayerName", 2);
+		yaml.save(file);
+
+		assertEquals(Map.of(playerId, 2), CurrentHomesStore.load(file, name -> {
+			assertEquals("OldPlayerName", name);
+			return playerId;
+		}));
+	}
+}