allow binding a GraphQL Any field to a struct method returning `*an…

…y` (#2644)

* allow binding GQL `Any` field to struct method returning `*any`

* add singlefile tests for binding to `*any` case

* add followschema tests for binding to `*any` case

* make ptr_to_any binding tests follow binding conventions better

codegen/config/binder.go

@@ -252,6 +252,14 @@ func (t *TypeReference) IsPtrToSlice() bool {
 	return false
 }
 
+func (t *TypeReference) IsPtrToIntf() bool {
+	if t.IsPtr() {
+		_, isPointerToInterface := t.GO.(*types.Pointer).Elem().(*types.Interface)
+		return isPointerToInterface
+	}
+	return false
+}
+
 func (t *TypeReference) IsNamed() bool {
 	_, isSlice := t.GO.(*types.Named)
 	return isSlice

codegen/testserver/followschema/ptr_to_any.go

@@ -0,0 +1,9 @@
+package followschema
+
+type PtrToAnyContainer struct {
+	PtrToAny *any
+}
+
+func (c *PtrToAnyContainer) Binding() *any {
+	return c.PtrToAny
+}

codegen/testserver/followschema/ptr_to_any.graphql

@@ -0,0 +1,10 @@
+scalar Any
+
+type PtrToAnyContainer {
+    ptrToAny: Any
+    binding: Any
+}
+
+extend type Query {
+    ptrToAnyContainer: PtrToAnyContainer!
+}

codegen/testserver/followschema/ptr_to_any_test.go

@@ -0,0 +1,37 @@
+package followschema
+
+import (
+	"context"
+	"testing"
+
+	"github.com/99designs/gqlgen/client"
+	"github.com/99designs/gqlgen/graphql/handler"
+	"github.com/stretchr/testify/require"
+)
+
+func TestPtrToAny(t *testing.T) {
+	resolvers := &Stub{}
+
+	c := client.New(handler.NewDefaultServer(NewExecutableSchema(Config{Resolvers: resolvers})))
+
+	var a any = `{"some":"thing"}`
+	resolvers.QueryResolver.PtrToAnyContainer = func(ctx context.Context) (wrappedStruct *PtrToAnyContainer, e error) {
+		ptrToAnyContainer := PtrToAnyContainer{
+			PtrToAny: &a,
+		}
+		return &ptrToAnyContainer, nil
+	}
+
+	t.Run("binding to pointer to any", func(t *testing.T) {
+		var resp struct {
+			PtrToAnyContainer struct {
+				Binding *any
+			}
+		}
+
+		err := c.Post(`query { ptrToAnyContainer { binding }}`, &resp)
+		require.NoError(t, err)
+
+		require.Equal(t, &a, resp.PtrToAnyContainer.Binding)
+	})
+}

codegen/testserver/followschema/resolver.go

@@ -362,6 +362,11 @@ func (r *queryResolver) PrimitiveStringObject(ctx context.Context) ([]PrimitiveS
 	panic("not implemented")
 }
 
+// PtrToAnyContainer is the resolver for the ptrToAnyContainer field.
+func (r *queryResolver) PtrToAnyContainer(ctx context.Context) (*PtrToAnyContainer, error) {
+	panic("not implemented")
+}
+
 // PtrToSliceContainer is the resolver for the ptrToSliceContainer field.
 func (r *queryResolver) PtrToSliceContainer(ctx context.Context) (*PtrToSliceContainer, error) {
 	panic("not implemented")