Fix Manga Meta, add Manga Meta test (#245)

* Fix Manga Meta, add Manga Meta test

* Tweak assertion strings

server/src/test/kotlin/suwayomi/tachidesk/manga/impl/MangaTest.kt

@@ -0,0 +1,61 @@
+package suwayomi.tachidesk.manga.impl
+
+/*
+ * Copyright (C) Contributors to the Suwayomi project
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+import org.junit.jupiter.api.AfterEach
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.TestInstance
+import suwayomi.tachidesk.manga.model.table.MangaMetaTable
+import suwayomi.tachidesk.manga.model.table.MangaTable
+import suwayomi.tachidesk.test.ApplicationTest
+import suwayomi.tachidesk.test.clearTables
+import suwayomi.tachidesk.test.createLibraryManga
+
+@TestInstance(TestInstance.Lifecycle.PER_CLASS)
+class MangaTest : ApplicationTest() {
+    @Test
+    fun getMangaMeta() {
+        val metaManga = createLibraryManga("META_TEST")
+        val emptyMeta = Manga.getMangaMetaMap(metaManga).size
+        assertEquals(0, emptyMeta, "Default Manga meta should be empty at start")
+
+        Manga.modifyMangaMeta(metaManga, "test", "value")
+        assertEquals(1, Manga.getMangaMetaMap(metaManga).size, "Manga meta should have one member")
+        assertEquals("value", Manga.getMangaMetaMap(metaManga)["test"], "Manga meta use the value 'value' for key 'test'")
+
+        Manga.modifyMangaMeta(metaManga, "test", "newValue")
+        assertEquals(
+            1,
+            Manga.getMangaMetaMap(metaManga).size,
+            "Manga meta should still only have one pair"
+        )
+        assertEquals(
+            "newValue", Manga.getMangaMetaMap(metaManga)["test"],
+            "Manga meta with key 'test' should use the value `newValue`"
+        )
+
+        Manga.modifyMangaMeta(metaManga, "test2", "value2")
+        assertEquals(
+            2, Manga.getMangaMetaMap(metaManga).size,
+            "Manga Meta should have an additional pair"
+        )
+        assertEquals(
+            "value2", Manga.getMangaMetaMap(metaManga)["test2"],
+            "Manga Meta for key 'test2' should be 'value2'"
+        )
+    }
+
+    @AfterEach
+    internal fun tearDown() {
+        clearTables(
+            MangaMetaTable,
+            MangaTable
+        )
+    }
+}