fix patternproperties handling in SpecFilter

modules/swagger-core/src/main/java/io/swagger/v3/core/filter/SpecFilter.java

@@ -255,6 +255,19 @@ protected Map<String, Schema> filterComponentsSchema(OpenAPISpecFilter filter, M
                     }
                 }
 
+                Map<String, Schema> clonedPatternProperties = new LinkedHashMap<>();
+                if (filteredDefinition.get().getPatternProperties() != null) {
+                    for (Object propName : filteredDefinition.get().getPatternProperties().keySet()) {
+                        Schema property = (Schema) filteredDefinition.get().getPatternProperties().get(propName);
+                        if (property != null) {
+                            Optional<Schema> filteredProperty = filter.filterSchemaProperty(property, definition, (String) propName, params, cookies, headers);
+                            if (filteredProperty.isPresent()) {
+                                clonedPatternProperties.put((String) propName, filteredProperty.get());
+                            }
+                        }
+                    }
+                }
+
                 try {
                     // TODO solve this, and generally handle clone and passing references
                     Schema clonedModel;
@@ -269,6 +282,12 @@ protected Map<String, Schema> filterComponentsSchema(OpenAPISpecFilter filter, M
                     if (!clonedProperties.isEmpty()) {
                         clonedModel.setProperties(clonedProperties);
                     }
+                    if(clonedModel.getPatternProperties() != null) {
+                        clonedModel.getPatternProperties().clear();
+                    }
+                    if(!clonedPatternProperties.isEmpty()) {
+                        clonedModel.setPatternProperties(clonedPatternProperties);
+                    }
                     clonedComponentsSchema.put(key, clonedModel);
 
                 } catch (IOException e) {
@@ -304,6 +323,13 @@ private void addSchemaRef(Schema schema, Set<String> referencedDefinitions) {
             addSchemaRef((Schema)schema.getAdditionalProperties(), referencedDefinitions);
         }
 
+        if (schema.getPatternProperties() != null) {
+            for (Object propName : schema.getPatternProperties().keySet()) {
+                Schema property = (Schema) schema.getPatternProperties().get(propName);
+                addSchemaRef(property, referencedDefinitions);
+            }
+        }
+
         if (schema instanceof ArraySchema &&
                 ((ArraySchema) schema).getItems() != null) {
             addSchemaRef(((ArraySchema) schema).getItems(), referencedDefinitions);

modules/swagger-core/src/test/java/io/swagger/v3/core/filter/SpecFilterTest.java

@@ -297,10 +297,11 @@ public void shouldRemoveBrokenNestedRefsKeepComposedSchemas() throws IOException
         final RemoveUnreferencedDefinitionsFilter remover = new RemoveUnreferencedDefinitionsFilter();
         final OpenAPI filtered = new SpecFilter().filter(openAPI, remover, null, null, null);
 
-        assertEquals(filtered.getComponents().getSchemas().size(), 4, "Expected to have parent and abstract child with both implementations schemas");
+        assertEquals(filtered.getComponents().getSchemas().size(), 5, "Expected to have parent and abstract child with both implementations schemas");
         assertTrue(filtered.getComponents().getSchemas().containsKey("SomeChild1ImplObject"), "Schemas should contains child 1 implementation");
         assertTrue(filtered.getComponents().getSchemas().containsKey("SomeChild2ImplObject"), "Schemas should contains child 2 implementation");
         assertTrue(filtered.getComponents().getSchemas().containsKey("SomeChildObject"), "Schemas should contains child abstract parent");
+        assertTrue(filtered.getComponents().getSchemas().containsKey("PatternPropertiesReferencedObject"), "Schemas should contains pattern properties referenced schema");
     }
 
     @Test

modules/swagger-core/src/test/resources/specFiles/3.1.0/composed-schema-3.1.json

@@ -18,6 +18,9 @@
       "SomeChildObject": {
         "description": "Some child object"
       },
+      "PatternPropertiesReferencedObject": {
+        "description": "An object schema with is ONLY referenced via pattern properties"
+      },
       "SomeParentObject": {
         "description": "Some parent object",
         "properties": {
@@ -37,6 +40,11 @@
               }
             ]
           }
+        },
+        "patternProperties": {
+          "somePattern": {
+            "$ref": "#/components/schemas/PatternPropertiesReferencedObject"
+          }
         }
       }
     }