Added both options for overrides

- Added the previous settings override in base again
- Added a system property to override the settings folder within tests

Author: Stefterv

app/src/processing/app/Base.java

@@ -2216,6 +2216,10 @@ static public InputStream getLibStream(String filename) throws IOException {
    * @deprecated use processing.utils.Settings.getFolder() instead, this method will invoke AWT
    */
   static public File getSettingsFolder() {
+      var override = getSettingsOverride();
+      if (override != null) {
+          return override;
+      }
       try {
           return processing.utils.Settings.getFolder();
       } catch (processing.utils.Settings.SettingsFolderException e) {

app/utils/src/main/java/processing/utils/Settings.java

@@ -18,7 +18,10 @@ public static File getFolder() throws SettingsFolderException {
     }
 
     private static File getFolderForPlatform() throws SettingsFolderException {
-        // TODO: Detect override file,
+        var settingsOverride = System.getProperty("processing.settings.folder");
+        if (settingsOverride != null && !settingsOverride.isEmpty()) {
+            return new File(settingsOverride);
+        }
 
         if (Platform.isWindows()) {
             var options = new String[]{

app/utils/src/test/java/SettingsTest.java

@@ -0,0 +1,40 @@
+import org.junit.jupiter.api.Test;
+import processing.utils.Settings;
+
+import java.io.IOException;
+import java.nio.file.Files;
+
+public class SettingsTest {
+
+    /**
+     * Requesting the settings folder should create it if it doesn't exist
+     */
+    @Test
+    public void testSettingsFolder() {
+        try {
+            var folder = Settings.getFolder();
+            assert (folder.exists());
+        } catch (Settings.SettingsFolderException e) {
+            assert (false);
+        }
+    }
+
+    /**
+     * Overriding the settings folder via system property should work
+     */
+    @Test
+    public void testOverrideFolder() throws IOException {
+        var settings = Files.createTempDirectory("settings_test");
+        System.setProperty("processing.settings.folder", settings.toString());
+
+        try {
+            var folder = Settings.getFolder();
+            assert (folder.toPath().toString().equals(settings.toString()));
+        } catch (Settings.SettingsFolderException e) {
+            assert (false);
+        } finally {
+            System.clearProperty("processing.settings.folder");
+            Files.deleteIfExists(settings);
+        }
+    }
+}