Ensure chainModel is combined with final model. Fixes #9626

Author: graemerocher

grails-plugin-controllers/src/main/groovy/grails/artefact/controller/support/ResponseRedirector.groovy

@@ -25,6 +25,7 @@ import grails.web.mapping.UrlMappings
 import grails.web.mapping.UrlMappingsHolder
 import grails.web.mapping.mvc.RedirectEventListener
 import grails.web.mapping.mvc.exceptions.CannotRedirectException
+import grails.web.mvc.FlashScope
 import groovy.transform.CompileStatic
 import org.grails.core.artefact.ControllerArtefactHandler
 import org.grails.core.artefact.DomainClassArtefactHandler
@@ -124,7 +125,7 @@ trait ResponseRedirector implements WebAttributes {
      * @return The chainModel
      */
     Map getChainModel() {
-        (Map)getFlash().get("chainModel")
+        (Map)getFlash().get(FlashScope.CHAIN_MODEL)
     }
 
 

grails-web-common/src/main/groovy/grails/web/mvc/FlashScope.java

@@ -28,7 +28,12 @@
  * @author Graeme Rocher
  */
 @SuppressWarnings("rawtypes")
-public interface FlashScope extends Map, Serializable {
+public interface FlashScope extends Map<String, Object>, Serializable {
+
+    /**
+     * The attribute containing the chain model
+     */
+    String CHAIN_MODEL = "chainModel";
 
     /**
      * Sets the flash scope to the next state upon a new request

grails-web-common/src/main/groovy/org/grails/web/servlet/GrailsFlashScope.java

@@ -108,27 +108,27 @@ public boolean containsValue(Object value) {
         return (current.containsValue(value) || next.containsValue(value));
     }
 
-    public Collection values() {
+    public Collection<Object> values() {
         Collection c = new ArrayList();
         c.addAll(current.values());
         c.addAll(next.values());
         return c;
     }
 
-    public void putAll(Map t) {
-        for (Map.Entry<Object, Object> entry : ((Map<Object,Object>)t).entrySet()) {
+    public void putAll(Map<? extends String, ? extends Object> t) {
+        for (Entry<? extends String, ? extends Object> entry : t.entrySet()) {
             put(entry.getKey(), entry.getValue());
         }
     }
 
-    public Set entrySet() {
+    public Set<Map.Entry<String, Object>> entrySet() {
         Set entrySet = new HashSet();
         entrySet.addAll(current.entrySet());
         entrySet.addAll(next.entrySet());
         return entrySet;
     }
 
-    public Set keySet() {
+    public Set<String> keySet() {
         Set keySet = new HashSet();
         keySet.addAll(current.keySet());
         keySet.addAll(next.keySet());
@@ -153,7 +153,7 @@ public Object remove(Object key) {
         return next.remove(key);
     }
 
-    public Object put(Object key, Object value) {
+    public Object put(String key, Object value) {
         // create the session if it doesn't exist
         registerWithSessionIfNecessary();
         if (current.containsKey(key)) {

grails-web-url-mappings/src/main/groovy/org/grails/web/mapping/mvc/UrlMappingsInfoHandlerAdapter.groovy

@@ -5,6 +5,7 @@ import grails.util.Environment
 import grails.web.mapping.LinkGenerator
 import grails.web.mapping.ResponseRedirector
 import grails.web.mapping.UrlMappingInfo
+import grails.web.mvc.FlashScope
 import groovy.transform.CompileStatic
 import org.grails.web.servlet.mvc.ActionResultTransformer
 import org.grails.web.servlet.mvc.GrailsWebRequest
@@ -98,7 +99,17 @@ class UrlMappingsInfoHandlerAdapter implements HandlerAdapter, ApplicationContex
                 }
                 else if(result instanceof Map) {
                     String viewName = controllerClass.actionUriToViewName(action)
-                    return new ModelAndView(viewName, new HashMap<String, Object>((Map)result))
+                    def finalModel = new HashMap<String, Object>()
+                    def flashScope = webRequest.getFlashScope()
+                    if(!flashScope.isEmpty()) {
+                        def chainModel = flashScope.get(FlashScope.CHAIN_MODEL)
+                        if(chainModel instanceof Map) {
+                            finalModel.putAll((Map)chainModel)
+                        }
+                    }
+                    finalModel.putAll((Map)result)
+
+                    return new ModelAndView(viewName, finalModel)
                 }
                 else if(result instanceof ModelAndView) {
                     return (ModelAndView) result