Make GraphQLRequest.Extensions dictionary (#556)

Author: sungam3r

src/GraphQL.Client/GraphQLHttpRequest.cs

@@ -11,11 +11,13 @@ public GraphQLHttpRequest()
     {
     }
 
-    public GraphQLHttpRequest(string query, object? variables = null, string? operationName = null) : base(query, variables, operationName)
+    public GraphQLHttpRequest(string query, object? variables = null, string? operationName = null, Dictionary<string, object?>? extensions = null)
+        : base(query, variables, operationName, extensions)
     {
     }
 
-    public GraphQLHttpRequest(GraphQLRequest other) : base(other)
+    public GraphQLHttpRequest(GraphQLRequest other)
+        : base(other)
     {
     }
 

src/GraphQL.Primitives/GraphQLRequest.cs

@@ -40,15 +40,15 @@ public object? Variables
     /// <summary>
     /// Represents the request extensions
     /// </summary>
-    public object? Extensions
+    public Dictionary<string, object?>? Extensions
     {
-        get => TryGetValue(EXTENSIONS_KEY, out object value) ? value : null;
+        get => TryGetValue(EXTENSIONS_KEY, out object value) && value is Dictionary<string, object?> d ? d : null;
         set => this[EXTENSIONS_KEY] = value;
     }
 
     public GraphQLRequest() { }
 
-    public GraphQLRequest(string query, object? variables = null, string? operationName = null, object? extensions = null)
+    public GraphQLRequest(string query, object? variables = null, string? operationName = null, Dictionary<string, object?>? extensions = null)
     {
         Query = query;
         Variables = variables;

tests/GraphQL.Client.Serializer.Tests/TestData/SerializeToStringTestData.cs

@@ -10,6 +10,10 @@ public IEnumerator<object[]> GetEnumerator()
             "{\"query\":\"simplequerystring\",\"variables\":null,\"operationName\":null,\"extensions\":null}",
             new GraphQLRequest("simple query string")
         };
+        yield return new object[] {
+            "{\"query\":\"simplequerystring\",\"variables\":null,\"operationName\":null,\"extensions\":{\"a\":\"abc\",\"b\":true,\"c\":{\"d\":42}}}",
+            new GraphQLRequest("simple query string", extensions: new Dictionary<string, object?> { ["a"] = "abc", ["b"] = true, ["c"] = new Dictionary<string, object> { ["d"] = 42 } })
+        };
         yield return new object[] {
             "{\"query\":\"simplequerystring\",\"variables\":{\"camelCaseProperty\":\"camelCase\",\"PascalCaseProperty\":\"PascalCase\"},\"operationName\":null,\"extensions\":null}",
             new GraphQLRequest("simple query string", new { camelCaseProperty = "camelCase", PascalCaseProperty = "PascalCase"})