Merge pull request #8 from dgraph-io/jatin/GRAPHQL-745

fix(GraphQL): This PR change the coerced slice to type interface.

validator/vars.go

@@ -10,8 +10,6 @@ import (
 	"github.com/dgraph-io/gqlparser/v2/gqlerror"
 )
 
-var UnexpectedType = fmt.Errorf("Unexpected Type")
-
 // VariableValues coerces and validates variable values
 func VariableValues(schema *ast.Schema, op *ast.OperationDefinition, variables map[string]interface{}) (map[string]interface{}, *gqlerror.Error) {
 	coercedVars := map[string]interface{}{}
@@ -82,9 +80,10 @@ func (v *varValidator) validateVarType(typ *ast.Type, val reflect.Value) (reflec
 		if val.Kind() != reflect.Slice {
 			// GraphQL spec says that non-null values should be coerced to an array when possible.
 			// Hence if the value is not a slice, we create a slice and add val to it.
-			slc := reflect.MakeSlice(reflect.SliceOf(val.Type()), 0, 0)
-			slc = reflect.Append(slc, val)
-			val = slc
+			slc := make([]interface{}, 0)
+			slc = append(slc, val.Interface())
+			val = reflect.ValueOf(slc)
+			val.Convert(val.Type())
 		}
 		for i := 0; i < val.Len(); i++ {
 			resetPath()

validator/vars_test.go

@@ -157,7 +157,7 @@ func TestValidateVars(t *testing.T) {
 				"var": map[string]interface{}{"name": "hello"},
 			})
 			require.Nil(t, gerr)
-			require.EqualValues(t, []map[string]interface{}{{"name": "hello"}}, vars["var"])
+			require.EqualValues(t, []interface{}{map[string]interface{}{"name": "hello"}}, vars["var"])
 		})
 
 		t.Run("non-null int value should be coerced to an array", func(t *testing.T) {
@@ -166,7 +166,7 @@ func TestValidateVars(t *testing.T) {
 				"var": 5,
 			})
 			require.Nil(t, gerr)
-			expected := []int{5}
+			expected := []interface{}{5}
 			require.EqualValues(t, expected, vars["var"])
 		})
 
@@ -176,7 +176,7 @@ func TestValidateVars(t *testing.T) {
 				"var": []map[string]interface{}{{"and": 5}},
 			})
 			require.Nil(t, gerr)
-			expected := []map[string]interface{}{{"and": []int{5}}}
+			expected := []map[string]interface{}{{"and": []interface{}{5}}}
 			require.EqualValues(t, expected, vars["var"])
 		})