Add Api Enum Unit tests

src/test/java/EnumTestHelper.java

@@ -0,0 +1,116 @@
+/*
+ *    This file is part of the Distant Horizons mod (formerly the LOD Mod),
+ *    licensed under the GNU LGPL v3 License.
+ *
+ *    Copyright (C) 2020-2022  James Seibel
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the GNU Lesser General Public License as published by
+ *    the Free Software Foundation, version 3.
+ *
+ *    This program 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 Lesser General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Lesser General Public License
+ *    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import org.junit.Assert;
+
+import java.io.File;
+import java.io.FilenameFilter;
+import java.net.URL;
+import java.util.ArrayList;
+
+/**
+ * A list of methods related to the Enum unit tests.
+ *
+ * @author James Seibel
+ * @version 6-9-2022
+ */
+public class EnumTestHelper
+{
+	
+	/**
+	 * Returns a list of every Enum in the package with the given full name.
+	 *
+	 * @param packageFullName includes the package path
+	 */
+	@SuppressWarnings("unchecked")
+	public static ArrayList<Class<? extends Enum<?>>> getAllEnumsFromPackage(String packageFullName)
+	{
+		ArrayList<Class<? extends Enum<?>>> enumList = new ArrayList<>();
+		URL packageRoot = Thread.currentThread().getContextClassLoader().getResource(packageFullName.replace(".", "/"));
+		
+		// find all .class files in the package folder
+		Assert.assertNotNull("No enums found in the package [" + packageFullName + "].", packageRoot); // asserts can be used since this method should only ever be used in the context of unit tests
+		File[] files = new File(packageRoot.getFile()).listFiles(new FilenameFilter()
+		{
+			public boolean accept(File dir, String name)
+			{
+				return name.endsWith(".class");
+			}
+		});
+		
+		// get the enums from each file
+		Assert.assertNotNull("No files found in the package [" + packageFullName + "].", files);
+		for (File file : files)
+		{
+			String className = file.getName().replaceAll(".class$", "");
+			
+			// ignore internal classes
+			if (!className.contains("$"))
+			{
+				String fullClassName = packageFullName + "." + className;
+				try
+				{
+					// attempt to parse the file's class into an enum
+					Class<?> enumClass = Class.forName(fullClassName);
+					if (Enum.class.isAssignableFrom(enumClass))
+					{
+						enumList.add((Class<? extends Enum<?>>) enumClass);
+					}
+					else
+					{
+						System.out.println("The Class [" + fullClassName + "] isn't an enum.");
+					}
+				}
+				catch (ClassNotFoundException e)
+				{
+					System.out.println("No enum found with the full name [" + fullClassName + "].");
+				}
+			}
+		}
+		
+		return enumList;
+	}
+	
+	/**
+	 * Returns every loaded package that begins with the given string.
+	 *
+	 * Note: this will only search packages that have been loaded
+	 * at some point during the JVM's lifetime.
+	 * To Make sure the package(s) you want to find are loaded you can
+	 * initialize an object from that package to load it.
+	 */
+	public static ArrayList<String> findPackageNamesStartingWith(String packagePrefix)
+	{
+		ArrayList<String> nestedPackages = new ArrayList<>();
+		
+		// search all the loaded packages
+		Package[] packageArray = Package.getPackages();
+		for (Package pack : packageArray)
+		{
+			String packageName = pack.getName();
+			if (packageName.startsWith(packagePrefix))
+			{
+				nestedPackages.add(packageName);
+			}
+		}
+		
+		return nestedPackages;
+	}
+	
+}