test: refactor json.Marshaler and json.Unmarshaler stubs

cloudfoundry · May 21, 2020 · ff76c24 · ff76c24
1 parent ef62926
commit ff76c24
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Showing 3 changed files with 24 additions and 15 deletions.
diff --git a/jsonry_suite_test.go b/jsonry_suite_test.go
@@ -10,20 +10,24 @@ import (
 	. "github.com/onsi/gomega"
 )
 
-type implementsJSONMarshaler struct{ value bool }
+type implementsJSONMarshaler struct {
+	bytes []byte
+	err   error
+}
 
-func (j implementsJSONMarshaler) MarshalJSON() ([]byte, error) {
-	if j.value {
-		return nil, errors.New("ouch")
-	}
-	return json.Marshal("hello")
+func (i implementsJSONMarshaler) MarshalJSON() ([]byte, error) {
+	return i.bytes, i.err
+}
+
+type implementsJSONUnmarshaler struct {
+	hasBeenSet bool
 }
 
-func (j *implementsJSONMarshaler) UnmarshalJSON(input []byte) error {
+func (i *implementsJSONUnmarshaler) UnmarshalJSON(input []byte) error {
 	if bytes.Equal(input, []byte(`"fail"`)) {
 		return errors.New("ouch")
 	}
-	j.value = true
+	i.hasBeenSet = true
 	return nil
 }
 

diff --git a/marshal_test.go b/marshal_test.go
@@ -1,6 +1,8 @@
 package jsonry_test
 
 import (
+	"errors"
+
 	"code.cloudfoundry.org/jsonry"
 	. "github.com/onsi/ginkgo"
 	. "github.com/onsi/gomega"
@@ -168,9 +170,12 @@ var _ = Describe("Marshal", func() {
 		})
 
 		It("marshals a json.Marshaler", func() {
-			expectToMarshal(struct{ J implementsJSONMarshaler }{J: implementsJSONMarshaler{value: false}}, `{"J":"hello"}`)
-			expectToMarshal(struct{ J *implementsJSONMarshaler }{J: &implementsJSONMarshaler{value: false}}, `{"J":"hello"}`)
-			expectToFail(struct{ J implementsJSONMarshaler }{J: implementsJSONMarshaler{value: true}}, `error from MarshaJSON() call at field "J" (type "jsonry_test.implementsJSONMarshaler"): ouch`)
+			expectToMarshal(struct{ I implementsJSONMarshaler }{I: implementsJSONMarshaler{bytes: []byte(`"hello"`)}}, `{"I":"hello"}`)
+			expectToMarshal(struct{ I *implementsJSONMarshaler }{I: &implementsJSONMarshaler{bytes: []byte(`"hello"`)}}, `{"I":"hello"}`)
+			expectToMarshal(struct{ I *implementsJSONMarshaler }{I: (*implementsJSONMarshaler)(nil)}, `{"I":null}`)
+
+			expectToFail(struct{ I implementsJSONMarshaler }{I: implementsJSONMarshaler{err: errors.New("ouch")}}, `error from MarshaJSON() call at field "I" (type "jsonry_test.implementsJSONMarshaler"): ouch`)
+			expectToFail(struct{ I implementsJSONMarshaler }{I: implementsJSONMarshaler{}}, `error parsing MarshaJSON() output "" at field "I" (type "jsonry_test.implementsJSONMarshaler"): unexpected end of JSON input`)
 		})
 
 		It("marshals from named types and type aliases", func() {

diff --git a/unmarshal_test.go b/unmarshal_test.go
@@ -289,12 +289,12 @@ var _ = Describe("Unmarshal", func() {
 			expectToFail(&s, `{}`, `maps must only have string keys for "int" at field "S" (type "map[int]string")`)
 		})
 
-		It("unmarshals a json.Marshaler field", func() {
-			var s struct{ S implementsJSONMarshaler }
+		It("unmarshals into json.Unmarshaler field", func() {
+			var s struct{ S implementsJSONUnmarshaler }
 			unmarshal(&s, `{"S":"ok"}`)
-			Expect(s.S).To(Equal(implementsJSONMarshaler{value: true}))
+			Expect(s.S).To(Equal(implementsJSONUnmarshaler{hasBeenSet: true}))
 
-			expectToFail(&s, `{"S":"fail"}`, `error from UnmarshalJSON() call at field "S" (type "jsonry_test.implementsJSONMarshaler"): ouch`)
+			expectToFail(&s, `{"S":"fail"}`, `error from UnmarshalJSON() call at field "S" (type "jsonry_test.implementsJSONUnmarshaler"): ouch`)
 		})
 
 		It("unmarshals into named types and type aliases", func() {