fix issue #37

container.go

@@ -92,20 +92,20 @@ func (c Container) bind(resolver interface{}, name string, singleton bool) error
 		return errors.New("container: the resolver must be a function")
 	}
 
-	for i := 0; i < reflectedResolver.NumOut(); i++ {
-		if _, exist := c[reflectedResolver.Out(i)]; !exist {
-			c[reflectedResolver.Out(i)] = make(map[string]binding)
+	if reflectedResolver.NumOut() > 0 {
+		if _, exist := c[reflectedResolver.Out(0)]; !exist {
+			c[reflectedResolver.Out(0)] = make(map[string]binding)
 		}
 
-		if singleton {
-			instance, err := c.invoke(resolver)
-			if err != nil {
-				return err
-			}
+		instance, err := c.invoke(resolver)
+		if err != nil {
+			return err
+		}
 
-			c[reflectedResolver.Out(i)][name] = binding{resolver: resolver, instance: instance}
+		if singleton {
+			c[reflectedResolver.Out(0)][name] = binding{resolver: resolver, instance: instance}
 		} else {
-			c[reflectedResolver.Out(i)][name] = binding{resolver: resolver}
+			c[reflectedResolver.Out(0)][name] = binding{resolver: resolver}
 		}
 	}
 

container_test.go

@@ -105,6 +105,13 @@ func TestContainer_Singleton(t *testing.T) {
 	assert.NoError(t, err)
 }
 
+func TestContainer_Singleton_With_Resolve_That_Returns_Error(t *testing.T) {
+	err := instance.Singleton(func() (Shape, error) {
+		return nil, errors.New("app: error")
+	})
+	assert.Error(t, err, "app: error")
+}
+
 func TestContainer_Singleton_With_NonFunction_Resolver_It_Should_Fail(t *testing.T) {
 	err := instance.Singleton("STRING!")
 	assert.EqualError(t, err, "container: the resolver must be a function")
@@ -166,21 +173,27 @@ func TestContainer_Transient_With_Resolve_That_Returns_Error(t *testing.T) {
 	err := instance.Transient(func() (Shape, error) {
 		return nil, errors.New("app: error")
 	})
+	assert.Error(t, err, "app: error")
+
+	firstCall := true
+	err = instance.Transient(func() (Database, error) {
+		if firstCall {
+			firstCall = false
+			return &MySQL{}, nil
+		}
+		return nil, errors.New("app: second call error")
+	})
 	assert.NoError(t, err)
 
-	var s Shape
-	err = instance.Resolve(&s)
-	assert.Error(t, err, "app: error")
+	var db Database
+	err = instance.Resolve(&db)
+	assert.Error(t, err, "app: second call error")
 }
 
 func TestContainer_Transient_With_Resolve_With_Invalid_Signature_It_Should_Fail(t *testing.T) {
 	err := instance.Transient(func() (Shape, Database, error) {
 		return nil, nil, nil
 	})
-	assert.NoError(t, err)
-
-	var s Shape
-	err = instance.Resolve(&s)
 	assert.Error(t, err, "container: resolver function signature is invalid")
 }