Description
Hi diff team,
I am working on a project that is leveraging the library and there appears to be a problem with interfaces when serializing the change logs. The types get lost in translation.
I have created a simplified reproduction of the issue at hand that exemplifies the issue. In the example there is a type that has a field which is an interface where we are adding different types that qualify for the interface. When we serialize the changelog, then de-serialize the changelog, then apply it as a patch, you will see the error. The important piece is that it does not recognize what type it was from before the change log was serialized.
type Something interface {
Name() string
}
type A struct {
First string
Second string
}
func (a A) Name() string {
return a.First + a.Second
}
type B struct {
First string
Second string
}
func (b B) Name() string {
return b.First + b.Second
}
type Example struct {
This []Something
}
func TestChangeExample(t *testing.T) {
before := Example{This: []Something{A{First: "Joe", Second: "Shmo"}}}
after := Example{This: []Something{A{First: "Joe", Second: "Shmo"}, B{First: "Jane", Second: "Doe"}}}
differ, err := diff.NewDiffer(diff.ConvertCompatibleTypes())
if err != nil {
t.Fatal(err)
}
cl, err := differ.Diff(&before, &after)
if err != nil {
t.Fatal(err)
}
b, err := json.Marshal(&cl)
if err != nil {
t.Fatal(err)
}
var newCL diff.Changelog
err = json.Unmarshal(b, &newCL)
if err != nil {
t.Fatal(err)
}
pl := diff.Patch(newCL, &before)
for _, p := range pl {
if p.Errors != nil {
t.Fatal(p.Errors)
}
}
println("success?")
}In the Goland IDE inspection and comparison to the before after shows that it does not recognize the same type:
