JENKINS-75299 Jenkins not starting due to NPE

src/main/java/org/jenkinsci/plugins/scriptler/config/ScriptSet.java

@@ -33,7 +33,7 @@
  */
 public class ScriptSet {
     // have it sorted
-    protected final Set<Script> scriptSet = new TreeSet<>();
+    protected Set<Script> scriptSet = new TreeSet<>();
 
     public Script getScriptById(String id) {
         for (Script scr : scriptSet) {
@@ -89,6 +89,9 @@ private Script merge(Script origin, Script newScript) {
     }
 
     public final Set<Script> getScripts() {
+        if (scriptSet == null) {
+            scriptSet = new TreeSet<>();
+        }
         return Collections.unmodifiableSet(scriptSet);
     }
 
@@ -103,6 +106,9 @@ public final Set<Script> getUserScripts() {
     }
 
     public void setScripts(Set<Script> scripts) {
+        if (scriptSet == null) {
+            scriptSet = new TreeSet<>();
+        }
         scriptSet.clear();
         scriptSet.addAll(scripts);
     }

src/test/java/org/jenkinsci/plugins/scriptler/config/ScriptSetTest.java

@@ -0,0 +1,31 @@
+package org.jenkinsci.plugins.scriptler.config;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
+import java.util.Collections;
+import org.junit.jupiter.api.Test;
+
+public class ScriptSetTest {
+
+    @Test
+    public void testGetScriptsHandlesNull() {
+        ScriptSet scriptSet = new ScriptSet();
+
+        scriptSet.scriptSet = null;
+
+        assertNotNull(scriptSet.getScripts(), "getScripts() should never return null");
+        assertEquals(
+                Collections.emptySet(), scriptSet.getScripts(), "Should return empty set when internal state is null");
+    }
+
+    @Test
+    public void testSetScriptsHandlesNull() {
+        ScriptSet scriptSet = new ScriptSet();
+        scriptSet.scriptSet = null;
+
+        scriptSet.setScripts(Collections.emptySet());
+
+        assertNotNull(scriptSet.getScripts(), "Internal set should be initialized after setter");
+    }
+}