Adds some tests for the salvage helper

src/test/java/net/knarcraft/blacksmith/CustomServerMock.java

@@ -0,0 +1,31 @@
+package net.knarcraft.blacksmith;
+
+import be.seeseemelk.mockbukkit.ServerMock;
+import org.bukkit.Material;
+import org.bukkit.NamespacedKey;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.Recipe;
+import org.bukkit.inventory.ShapedRecipe;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * A custom server mock specifically for making the SalvageHelperTest work
+ */
+public class CustomServerMock extends ServerMock {
+
+    public @NotNull List<Recipe> getRecipesFor(@NotNull ItemStack itemStack) {
+        List<Recipe> validRecipes = new ArrayList<>();
+        if (itemStack.getType() == Material.DIAMOND_PICKAXE) {
+            ShapedRecipe recipe = new ShapedRecipe(NamespacedKey.minecraft("diamond_pickaxe"), itemStack);
+            recipe.shape("ddd", "asa", "asa");
+            recipe.setIngredient('d', Material.DIAMOND);
+            recipe.setIngredient('s', Material.STICK);
+            validRecipes.add(recipe);
+        }
+        return validRecipes;
+    }
+
+}

src/test/java/net/knarcraft/blacksmith/util/SalvageHelperTest.java

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+package net.knarcraft.blacksmith.util;
+
+import be.seeseemelk.mockbukkit.MockBukkit;
+import net.knarcraft.blacksmith.CustomServerMock;
+import org.bukkit.Material;
+import org.bukkit.Server;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.meta.Damageable;
+import org.bukkit.inventory.meta.ItemMeta;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
+
+/**
+ * A test class to test salvaging
+ */
+public class SalvageHelperTest {
+
+    private static Server server;
+
+    @BeforeAll
+    public static void setUp() {
+        server = MockBukkit.mock(new CustomServerMock());
+    }
+
+    @Test
+    public void getNullForInvalidItemTest() {
+        //Assert that a non-reforge-able item will return null
+        assertNull(SalvageHelper.getSalvage(server, new ItemStack(Material.POTATO, 1), null));
+    }
+
+    @Test
+    public void getNullForLessThanOneItemTest() {
+        //Assert that 0 or 1 items will return null
+        assertNull(SalvageHelper.getSalvage(server, new ItemStack(Material.IRON_AXE, 0), null));
+        assertNull(SalvageHelper.getSalvage(server, new ItemStack(Material.IRON_SWORD, -1), null));
+    }
+
+    @Test
+    public void getFullSalvageTest() {
+        Set<ItemStack> expectedSalvage = new HashSet<>();
+        expectedSalvage.add(new ItemStack(Material.DIAMOND, 3));
+        expectedSalvage.add(new ItemStack(Material.STICK, 2));
+        ItemStack itemToSalvage = new ItemStack(Material.DIAMOND_PICKAXE, 1);
+        //Note: Conversion to sets makes sure the order doesn't matter
+        assertEquals(expectedSalvage, new HashSet<>(SalvageHelper.getSalvage(server, itemToSalvage, null)));
+    }
+
+    @Test
+    public void getNonFullSalvageTest() {
+        List<ItemStack> expectedSalvage = new ArrayList<>();
+        expectedSalvage.add(new ItemStack(Material.DIAMOND, 3));
+        expectedSalvage.add(new ItemStack(Material.STICK, 2));
+        ItemStack itemToSalvage = new ItemStack(Material.DIAMOND_PICKAXE, 1);
+        ItemMeta meta = itemToSalvage.getItemMeta();
+        Damageable damageable = (Damageable) meta;
+        if (damageable != null) {
+            damageable.setDamage(100);
+        }
+        itemToSalvage.setItemMeta(meta);
+        List<ItemStack> salvage = SalvageHelper.getSalvage(server, itemToSalvage, null);
+        //Assert that some items are given
+        assertNotEquals(salvage, new ArrayList<>());
+        //Assert that a damaged item won't give full salvage
+        assertNotEquals(expectedSalvage, salvage);
+    }
+
+}