move packer.Unmarshaler interface to decode.Unmarshaler, so the metho…

…ds are actually visible

decode/decode.go

@@ -0,0 +1,13 @@
+package decode
+
+// Unmarshaler defines the api of Go types mapped to custom GraphQL scalar types
+type Unmarshaler interface {
+	// ImplementsGraphQLType maps the implementing custom Go type
+	// to the GraphQL scalar type in the schema.
+	ImplementsGraphQLType(name string) bool
+	// UnmarshalGraphQL is the custom unmarshaler for the implementing type
+	//
+	// This function will be called whenever you use the
+	// custom GraphQL scalar type as an input
+	UnmarshalGraphQL(input interface{}) error
+}

graphql.go

@@ -10,7 +10,6 @@ import (
 	"github.com/graph-gophers/graphql-go/errors"
 	"github.com/graph-gophers/graphql-go/internal/common"
 	"github.com/graph-gophers/graphql-go/internal/exec"
-	"github.com/graph-gophers/graphql-go/internal/exec/packer"
 	"github.com/graph-gophers/graphql-go/internal/exec/resolvable"
 	"github.com/graph-gophers/graphql-go/internal/exec/selected"
 	"github.com/graph-gophers/graphql-go/internal/query"
@@ -21,9 +20,6 @@ import (
 	"github.com/graph-gophers/graphql-go/trace"
 )
 
-// Unmarshaler defines the public api of Go types mapped to custom GraphQL scalar types
-type Unmarshaler = packer.Unmarshaler
-
 // ParseSchema parses a GraphQL schema and attaches the given root resolver. It returns an error if
 // the Go type signature of the resolvers does not match the schema. If nil is passed as the
 // resolver, then the schema can not be executed, but it may be inspected (e.g. with ToJSON).

internal/exec/packer/packer.go

@@ -6,6 +6,7 @@ import (
 	"reflect"
 	"strings"
 
+	"github.com/graph-gophers/graphql-go/decode"
 	"github.com/graph-gophers/graphql-go/errors"
 	"github.com/graph-gophers/graphql-go/internal/common"
 	"github.com/graph-gophers/graphql-go/internal/schema"
@@ -115,7 +116,7 @@ func (b *Builder) makePacker(schemaType common.Type, reflectType reflect.Type) (
 }
 
 func (b *Builder) makeNonNullPacker(schemaType common.Type, reflectType reflect.Type) (packer, error) {
-	if u, ok := reflect.New(reflectType).Interface().(Unmarshaler); ok {
+	if u, ok := reflect.New(reflectType).Interface().(decode.Unmarshaler); ok {
 		if !u.ImplementsGraphQLType(schemaType.String()) {
 			return nil, fmt.Errorf("can not unmarshal %s into %s", schemaType, reflectType)
 		}
@@ -323,23 +324,12 @@ func (p *unmarshalerPacker) Pack(value interface{}) (reflect.Value, error) {
 	}
 
 	v := reflect.New(p.ValueType)
-	if err := v.Interface().(Unmarshaler).UnmarshalGraphQL(value); err != nil {
+	if err := v.Interface().(decode.Unmarshaler).UnmarshalGraphQL(value); err != nil {
 		return reflect.Value{}, err
 	}
 	return v.Elem(), nil
 }
 
-type Unmarshaler interface {
-	// ImplementsGraphQLType maps the implementing custom Go type
-	// to the GraphQL scalar type in the schema.
-	ImplementsGraphQLType(name string) bool
-	// UnmarshalGraphQL is the custom unmarshaler for the implementing type
-	//
-	// This function will be called whenever you use the
-	// custom GraphQL scalar type as an input
-	UnmarshalGraphQL(input interface{}) error
-}
-
 func unmarshalInput(typ reflect.Type, input interface{}) (interface{}, error) {
 	if reflect.TypeOf(input) == typ {
 		return input, nil
@@ -391,7 +381,7 @@ func stripUnderscore(s string) string {
 
 // NullUnmarshaller is an unmarshaller that can handle a nil input
 type NullUnmarshaller interface {
-	Unmarshaler
+	decode.Unmarshaler
 	Nullable()
 }
 

internal/exec/resolvable/resolvable.go

@@ -6,6 +6,7 @@ import (
 	"reflect"
 	"strings"
 
+	"github.com/graph-gophers/graphql-go/decode"
 	"github.com/graph-gophers/graphql-go/internal/common"
 	"github.com/graph-gophers/graphql-go/internal/exec/packer"
 	"github.com/graph-gophers/graphql-go/internal/schema"
@@ -207,7 +208,7 @@ func makeScalarExec(t *schema.Scalar, resolverType reflect.Type) (Resolvable, er
 		implementsType = t.Name == "String"
 	case *bool:
 		implementsType = t.Name == "Boolean"
-	case packer.Unmarshaler:
+	case decode.Unmarshaler:
 		implementsType = r.ImplementsGraphQLType(t.Name)
 	}
 	if !implementsType {

time_test.go

@@ -7,6 +7,7 @@ import (
 	"time"
 
 	. "github.com/graph-gophers/graphql-go"
+	"github.com/graph-gophers/graphql-go/decode"
 )
 
 func TestTime_ImplementsUnmarshaler(t *testing.T) {
@@ -16,8 +17,8 @@ func TestTime_ImplementsUnmarshaler(t *testing.T) {
 		}
 	}()
 
-	// assert *Time implements Unmarshaler interface
-	var _ Unmarshaler = (*Time)(nil)
+	// assert *Time implements decode.Unmarshaler interface
+	var _ decode.Unmarshaler = (*Time)(nil)
 }
 
 func TestTime_ImplementsGraphQLType(t *testing.T) {