DateKeys/capsule/differential_test.go

package capsule_test

import (
	"crypto/sha256"
	"encoding/hex"
	"os"
	"path/filepath"
	"testing"

	"g.activething.com/go/DateKeys/internal/testkit"
)

// The differential corpus of the pre-unlock checks,
// testdata/vectors/inspect_differential.json, replays: every mutation of an
// official fixture gets exactly the recorded verdict of Inspect, ok or an
// error code at a step. genfixtures regenerates the corpus, so that a change
// of verdict also shows as a change of the file.
func TestInspectDifferentialCorpus(t *testing.T) {
	var f testkit.DifferentialFile
	if err := testkit.ReadJSON("../testdata/vectors/inspect_differential.json", &f); err != nil {
		t.Fatal(err)
	}
	if len(f.Mutations) < 1500 {
		t.Fatalf("%d mutations, want at least 1500", len(f.Mutations))
	}
	bases := make([][]byte, len(f.Bases))
	for i, b := range f.Bases {
		dkc, err := os.ReadFile(filepath.Join(fixtureDir, b.File))
		if err != nil {
			t.Fatal(err)
		}
		if sum := sha256.Sum256(dkc); hex.EncodeToString(sum[:]) != b.SHA256 {
			t.Fatalf("%s changed", b.File)
		}
		bases[i] = dkc
	}
	kinds := map[string]int{}
	for i, m := range f.Mutations {
		dkc, err := testkit.ApplyEdits(bases[m.Base], m.Edits)
		if err != nil {
			t.Fatalf("mutation %d: %v", i, err)
		}
		result, step := testkit.InspectVerdict(dkc)
		if result != m.Result || step != m.Step {
			t.Errorf("mutation %d (%s of %s, edits %v): got %s at step %d, want %s at step %d",
				i, m.Kind, f.Bases[m.Base].File, m.Edits, result, step, m.Result, m.Step)
		}
		kinds[m.Kind]++
	}
	for _, k := range []string{"flip", "byte", "truncate", "insert", "delete", "length", "header", "datekey", "age"} {
		if kinds[k] == 0 {
			t.Errorf("no mutation of kind %s", k)
		}
	}
}