Check round trip fuzzing.

lib/fuzz_test.go

@@ -17,21 +17,38 @@ func FuzzJd(f *testing.F) {
  return
  }
  if a == nil {
- t.Errorf("nil parsed input: %v", aStr)
+ t.Errorf("nil parsed input: %q", aStr)
  return
  }
  b, err := ReadJsonString(bStr)
  if err != nil {
  return
  }
  if b == nil {
- t.Errorf("nil parsed input: %v", bStr)
+ t.Errorf("nil parsed input: %q", bStr)
  return
  }
- diffAB := a.Diff(b)
- if diffAB == nil {
+ // Diff A and B.
+ d := a.Diff(b)
+ if d == nil {
  t.Errorf("nil diff of a and b")
  return
  }
+ diffABStr := d.Render()
+ diffAB, err := ReadDiffString(diffABStr)
+ if err != nil {
+ t.Errorf("error parsing diff string %q: %v", diffABStr, err)
+ return
+ }
+ // Apply diff to A to get B.
+ patchedA, err := a.Patch(diffAB)
+ if err != nil {
+ t.Errorf("applying patch %v to %v should give %v. Got err: %v", diffAB, aStr, bStr, err)
+ return
+ }
+ if !patchedA.Equals(b) {
+ t.Errorf("applying patch %v to %v should give %v. Got err: %v", diffAB, aStr, bStr, patchedA)
+ return
+ }
  })
 }