go port

keccak/keccak_test.go

@@ -0,0 +1,70 @@
+package keccak
+
+import (
+  "encoding/hex"
+  "testing"
+)
+
+func TestKeccak256KnownAnswers(t *testing.T) {
+  cases := []struct {
+    name string
+    in   string
+    want string
+  }{
+    {"empty", "", "c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470"},
+    {
+      "abc",
+      "abc",
+      "4e03657aea45a94fc7d47ba826c8d667c0d1e6e33a64a036ec44f58fa12d6c45",
+    },
+    {
+      "longer",
+      "The quick brown fox jumps over the lazy dog",
+      "4d741b6f1eb29cb2a9b9911c82f56fa8d73b04959d3d9d222895df6c0b28aa15",
+    },
+  }
+  for _, tc := range cases {
+    t.Run(tc.name, func(t *testing.T) {
+      sum := Hash256([]byte(tc.in))
+      got := hex.EncodeToString(sum[:])
+      if got != tc.want {
+        t.Fatalf("Hash256(%q) = %s, want %s", tc.in, got, tc.want)
+      }
+    })
+  }
+}
+
+func TestStreamingMatchesOneShot(t *testing.T) {
+  data := make([]byte, 0, 500)
+  for i := 0; i < 500; i++ {
+    data = append(data, byte(i))
+  }
+  oneShot := Hash256(data)
+
+  h := New()
+  for i := 0; i < len(data); i += 7 {
+    end := i + 7
+    if end > len(data) {
+      end = len(data)
+    }
+    h.Write(data[i:end])
+  }
+  if got := h.Sum256(); got != oneShot {
+    t.Fatalf("streaming digest differs from one-shot")
+  }
+}
+
+// TestSum256DoesNotDisturbState ensures Sum256 clones the state (hash.Hash
+// semantics) so repeated calls are stable.
+func TestSum256DoesNotDisturbState(t *testing.T) {
+  h := New()
+  h.Write([]byte("abc"))
+  first := h.Sum256()
+  second := h.Sum256()
+  if first != second {
+    t.Fatalf("Sum256 mutated state")
+  }
+  if first != Hash256([]byte("abc")) {
+    t.Fatalf("Sum256 mismatch with Hash256")
+  }
+}