[JENKINS-61438] IllegalArgumentException for ChoiceParameter on bindJSON saving job configuration

core/src/main/java/org/kohsuke/stapler/RequestImpl.java

@@ -734,16 +734,25 @@ public Object convertJSON(Object o) {
 
             if (l==null) {// single value conversion
                 Converter converter = Stapler.lookupConverter(type);
-                if (converter==null)
+                if (converter == null) {
+                    if (type == Object.class) {
+                        return o;
+                    }
                     throw new IllegalArgumentException("Unable to convert to "+type);
+                }
 
                 return converter.convert(type,o);
             } else {// single value in a collection
                 Converter converter = Stapler.lookupConverter(l.itemType);
-                if (converter==null)
-                    throw new IllegalArgumentException("Unable to convert to "+l.itemType);
-
-                l.add(converter.convert(l.itemType, o));
+                if (converter == null) {
+                    if (l.itemType == Object.class) {
+                        l.add(o);
+                    } else {
+                        throw new IllegalArgumentException("Unable to convert to "+l.itemType);
+                    }
+                } else {
+                    l.add(converter.convert(l.itemType, o));
+                }
                 return l.toCollection();
             }
         }

core/src/test/java/org/kohsuke/stapler/RequestImplTest.java

@@ -2,6 +2,7 @@
  * The MIT License
  *
  * Copyright (c) 2015, CloudBees, Inc.
+ * Copyright (c) 2020, Nikolas Falco
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -28,29 +29,106 @@
 import org.apache.http.entity.mime.MultipartEntityBuilder;
 import org.junit.Assert;
 import org.junit.Test;
+import org.jvnet.hudson.test.For;
+import org.jvnet.hudson.test.Issue;
+import org.mockito.Mockito;
+
+import net.sf.json.JSONObject;
 
 import javax.servlet.ReadListener;
+import javax.servlet.ServletContext;
 import javax.servlet.ServletException;
 import javax.servlet.ServletInputStream;
+import javax.servlet.http.HttpServletRequest;
+
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.File;
 import java.io.IOException;
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.Enumeration;
+import java.util.List;
 
 /**
  * @author <a href="mailto:[email protected]">[email protected]</a>
+ * @author Nikolas Falco
  */
 public class RequestImplTest {
 
+    @For(RequestImpl.class)
+    public static class SetterObject {
+        private List<String> choices;
+
+        @DataBoundConstructor
+        public SetterObject() {
+            choices = new ArrayList<String>();
+        }
+
+        @SuppressWarnings("unchecked")
+        @DataBoundSetter
+        public void setChoices(Object choices) {
+            if (choices instanceof String) {
+                for (String choice : ((String) choices).split("\n")) {
+                    this.choices.add(choice);
+                }
+            } else {
+                this.choices = (List<String>) choices;
+            }
+        }
+
+        public List<String> getChoices() {
+            return choices;
+        }
+
+    }
+
+    @Issue("JENKINS-61438")
+    @Test
+    public void verify_JSON_bind_work_with_setter_that_accept_object_type() throws Exception {
+        final Stapler stapler = new Stapler();
+        stapler.setWebApp(new WebApp(Mockito.mock(ServletContext.class)));
+        HttpServletRequest request = Mockito.mock(HttpServletRequest.class);
+        RequestImpl req = new RequestImpl(stapler, request, Collections.<AncestorImpl>emptyList(), null);
+
+        JSONObject json = new JSONObject();
+        json.put("$class", SetterObject.class.getName());
+        json.put("choices", "1\n2\n3");
+
+        SetterObject o = req.bindJSON(SetterObject.class, json);
+        Assert.assertEquals(o.getChoices(), Arrays.asList("1", "2", "3"));
+    }
+
     @Test
     public void test_multipart_formdata() throws IOException, ServletException {
         final Stapler stapler = new Stapler();
-        final byte[] buf = generateMultipartData();
+        final MockRequest mockRequest = mockRequest(generateMultipartData());
+
+        RequestImpl request = new RequestImpl(stapler, mockRequest, Collections.<AncestorImpl>emptyList(), null);
+
+        // Check that we can get the Form Fields. See https://github.com/stapler/stapler/issues/52
+        Assert.assertEquals("text1_val", request.getParameter("text1"));
+        Assert.assertEquals("text2_val", request.getParameter("text2"));
+
+        // Check that we can get the file
+        FileItem fileItem = request.getFileItem("pomFile");
+        Assert.assertNotNull(fileItem);
+
+        // Check getParameterValues
+        Assert.assertEquals("text1_val", request.getParameterValues("text1")[0]);
+
+        // Check getParameterNames
+        Assert.assertTrue(Collections.list(request.getParameterNames()).contains("p1"));
+        Assert.assertTrue(Collections.list(request.getParameterNames()).contains("text1"));
+
+        // Check getParameterMap
+        Assert.assertTrue(request.getParameterMap().containsKey("text1"));        
+    }
+
+    private MockRequest mockRequest(final byte[] buf) {
         final ByteArrayInputStream is = new ByteArrayInputStream(buf);
-        final MockRequest mockRequest = new MockRequest() {
+        return new MockRequest() {
             @Override
             public String getContentType() {
                 return "multipart/form-data; boundary=mpboundary";
@@ -100,26 +178,6 @@ public void setReadListener(ReadListener readListener) {
                 };
             }
         };
-
-        RequestImpl request = new RequestImpl(stapler, mockRequest, Collections.<AncestorImpl>emptyList(), null);
-
-        // Check that we can get the Form Fields. See https://github.com/stapler/stapler/issues/52
-        Assert.assertEquals("text1_val", request.getParameter("text1"));
-        Assert.assertEquals("text2_val", request.getParameter("text2"));
-
-        // Check that we can get the file
-        FileItem fileItem = request.getFileItem("pomFile");
-        Assert.assertNotNull(fileItem);
-
-        // Check getParameterValues
-        Assert.assertEquals("text1_val", request.getParameterValues("text1")[0]);
-
-        // Check getParameterNames
-        Assert.assertTrue(Collections.list(request.getParameterNames()).contains("p1"));
-        Assert.assertTrue(Collections.list(request.getParameterNames()).contains("text1"));
-
-        // Check getParameterMap
-        Assert.assertTrue(request.getParameterMap().containsKey("text1"));        
     }
 
     private byte[] generateMultipartData() throws IOException {