Adds a method for visiting IBaseDocument instances

Author: MaggieKimani1

src/Microsoft.OpenApi/Services/OpenApiReferenceResolver.cs

@@ -221,6 +221,8 @@ public override void Visit(ref JsonSchema schema)
             schema = builder.Build();
         }
 
+        public override void Visit(IBaseDocument document) { }
+
         private Dictionary<string, JsonSchema> ResolveJsonSchemas(IDictionary<string, JsonSchema> schemas)
         {
             var resolvedSchemas = new Dictionary<string, JsonSchema>();

src/Microsoft.OpenApi/Services/OpenApiVisitorBase.cs

@@ -243,7 +243,9 @@ public virtual void Visit(OpenApiExternalDocs externalDocs)
         public virtual void Visit(ref JsonSchema schema)
         {
         }
-        
+
+        public virtual void Visit(IBaseDocument document) { }
+
         /// <summary>
         /// Visits <see cref="JsonSchema"/>
         /// </summary>

src/Microsoft.OpenApi/Services/OpenApiWalker.cs

@@ -808,7 +808,7 @@ internal void Walk(OpenApiEncoding encoding)
         internal JsonSchema Walk(JsonSchema schema, bool isComponent = false)
         {
             if (schema == null
-                || (schema.GetRef() != null && !isComponent))
+                || ProcessSchemaAsReference(schema, isComponent))
             {
                 return schema;
             }
@@ -1162,6 +1162,18 @@ private bool ProcessAsReference(IOpenApiReferenceable referenceable, bool isComp
             }
             return isReference;
         }
+
+        private bool ProcessSchemaAsReference(IBaseDocument baseDocument, bool isComponent = false)
+        {
+            var schema = baseDocument as JsonSchema;
+            var isReference = schema?.GetRef() != null && !isComponent;
+            if (isReference)
+            {
+                _visitor.Visit(baseDocument);
+            }
+
+            return isReference;
+        }
     }
 
     /// <summary>

test/Microsoft.OpenApi.Tests/Walkers/WalkerLocationTests.cs

@@ -291,16 +291,15 @@ public override void Visit(OpenApiMediaType mediaType)
             Locations.Add(this.PathString);
         }
 
+        public override void Visit(IBaseDocument document)
+        {
+            var schema = document as JsonSchema;
+            VisitJsonSchema(schema);
+        }
+
         public override void Visit(ref JsonSchema schema)
         {
-            if (schema.GetRef() != null)
-            {
-                Locations.Add("referenceAt: " + this.PathString);
-            }
-            else
-            {
-                Locations.Add(this.PathString);
-            }
+            VisitJsonSchema(schema);
         }
 
         public override void Visit(IList<OpenApiTag> openApiTags)
@@ -317,5 +316,17 @@ public override void Visit(OpenApiServer server)
         {
             Locations.Add(this.PathString);
         }
+
+        private void VisitJsonSchema(JsonSchema schema)
+        {
+            if (schema.GetRef() != null)
+            {
+                Locations.Add("referenceAt: " + this.PathString);
+            }
+            else
+            {
+                Locations.Add(this.PathString);
+            }
+        }
     }
 }