[issue-9926] add "itemsDepth" property for nested properties

This allows variable-name generation for nested structures without
shadowing violations, like v${{itemsDepth}}.

Author: mitchnull

modules/swagger-codegen/src/main/java/io/swagger/codegen/CodegenProperty.java

@@ -46,6 +46,7 @@ public class CodegenProperty implements Cloneable {
     public List<String> _enum;
     public Map<String, Object> allowableValues;
     public CodegenProperty items;
+    public Integer itemsDepth;
     public Map<String, Object> vendorExtensions;
     public boolean hasValidation; // true if pattern, maximum, etc are set (only used in the mustache template)
     public boolean isInherited;

modules/swagger-codegen/src/main/java/io/swagger/codegen/DefaultCodegen.java

@@ -1596,12 +1596,24 @@ public String getterAndSetterCapitalize(String name) {
      * @return Codegen Property object
      */
     public CodegenProperty fromProperty(String name, Property p) {
+        return fromProperty(name, p, null);
+    }
+    /**
+     * Convert Swagger Property object to Codegen Property object
+     *
+     * @param name name of the property
+     * @param p Swagger property object
+     * @param itemsDepth the depth in nested containers or null
+     * @return Codegen Property object
+     */
+    protected CodegenProperty fromProperty(String name, Property p, Integer itemsDepth) {
         if (p == null) {
             LOGGER.error("unexpected missing property for name " + name);
             return null;
         }
 
         CodegenProperty property = CodegenModelFactory.newInstance(CodegenModelType.PROPERTY);
+        property.itemsDepth = itemsDepth;
         property.name = toVarName(name);
         property.baseName = name;
         property.nameInCamelCase = camelize(property.name, false);
@@ -1864,7 +1876,8 @@ public CodegenProperty fromProperty(String name, Property p) {
             if (itemName == null) {
                 itemName = property.name;
             }
-            CodegenProperty cp = fromProperty(itemName, ap.getItems());
+            CodegenProperty cp = fromProperty(itemName, ap.getItems(),
+                itemsDepth == null ? 1 : itemsDepth.intValue() + 1);
             updatePropertyForArray(property, cp);
         } else if (p instanceof MapProperty) {
             MapProperty ap = (MapProperty) p;
@@ -1877,7 +1890,8 @@ public CodegenProperty fromProperty(String name, Property p) {
             property.maxItems = ap.getMaxProperties();
 
             // handle inner property
-            CodegenProperty cp = fromProperty("inner", ap.getAdditionalProperties());
+            CodegenProperty cp = fromProperty("inner", ap.getAdditionalProperties(),
+                itemsDepth == null ? 1 : itemsDepth.intValue() + 1);
             updatePropertyForMap(property, cp);
         } else {
             setNonArrayMapProperty(property, type);