Add fuzz testing

1 files changed, 70 insertions, 6 deletions

diff --git a/oae2_test.go b/oae2_test.go
index 90cf84d..96b83af 100644
--- a/oae2_test.go
+++ b/oae2_test.go
@@ -17,14 +17,14 @@ func TestRoundTrip(t *testing.T) {
 	buf := new(bytes.Buffer)
 	w := NewWriter(buf, []byte(key), blockSize)
 	if _, err := io.WriteString(w, msg); err != nil {
-		t.Fatalf("NewWriter.Write failed: %s", err)
+		t.Fatalf("Writer.Write failed: %s", err)
 	}
 	if err := w.Close(); err != nil {
-		t.Fatalf("NewWriter.Close failed: %s", err)
+		t.Fatalf("Writer.Close failed: %s", err)
 	}
 	got, err := io.ReadAll(NewReader(buf, []byte(key), blockSize))
 	if err != nil {
-		t.Fatalf("NewReader.Read failed: %s", err)
+		t.Fatalf("Reader.Read failed: %s", err)
 	}
 	if string(got) != msg {
 		t.Errorf("Message failed to round-trip, got %q, want %q", got, msg)
@@ -41,16 +41,80 @@ func TestReadFromWriteTo(t *testing.T) {
 	buf := new(bytes.Buffer)
 	w := NewWriter(buf, []byte(key), blockSize)
 	if _, err := io.Copy(w, struct{ io.Reader }{strings.NewReader(msg)}); err != nil {
-		t.Fatalf("NewWriter.WriteTo failed: %s", err)
+		t.Fatalf("Writer.WriteTo failed: %s", err)
 	}
 	if err := w.Close(); err != nil {
-		t.Fatalf("NewWriter.Close failed: %s", err)
+		t.Fatalf("Writer.Close failed: %s", err)
 	}
 	got := new(strings.Builder)
 	if _, err := io.Copy(got, NewReader(buf, []byte(key), blockSize)); err != nil {
-		t.Fatalf("NewReader.Read failed: %s", err)
+		t.Fatalf("Reader.Read failed: %s", err)
 	}
 	if got.String() != msg {
 		t.Errorf("Message failed to round-trip, got %q, want %q", got, msg)
 	}
 }
+
+func FuzzRoundTrip(f *testing.F) {
+	f.Add(1, []byte("Hello World!"))
+	f.Fuzz(func(t *testing.T, segmentSize int, msg []byte) {
+		const password = "asdf"
+
+		if segmentSize <= 0 {
+			return
+		}
+		buf := new(bytes.Buffer)
+		w := NewWriter(buf, []byte(password), segmentSize)
+		n, err := w.Write(msg)
+		if err != nil {
+			t.Fatalf("Writer.Write(%q) failed: %s", msg, err)
+		}
+		if n != len(msg) {
+			t.Errorf("Writer.Write(%q) = %d, want %d", msg, n, len(msg))
+		}
+		if err := w.Close(); err != nil {
+			t.Fatalf("Writer.Close failed: %s", err)
+		}
+		got, err := io.ReadAll(NewReader(buf, []byte(password), segmentSize))
+		if err != nil {
+			t.Fatalf("Reader.Read failed: %s", err)
+		}
+		if !bytes.Equal(got, msg) {
+			t.Errorf("Message failed to round-trip, got %q, want %q", got, msg)
+		}
+	})
+}
+
+func FuzzReadFromWriteTo(f *testing.F) {
+	f.Add(1, "Hello World!")
+	f.Fuzz(func(t *testing.T, segmentSize int, msg string) {
+		const password = "asdf"
+
+		if segmentSize <= 0 {
+			return
+		}
+		buf := new(bytes.Buffer)
+		w := NewWriter(buf, []byte(password), segmentSize)
+		n, err := w.ReadFrom(strings.NewReader(msg))
+		if err != nil {
+			t.Fatalf("Writer.ReadFrom(%q) failed: %s", msg, err)
+		}
+		if n != int64(len(msg)) {
+			t.Errorf("Writer.Write(%q) = %d, want %d", msg, n, len(msg))
+		}
+		if err := w.Close(); err != nil {
+			t.Fatalf("Writer.Close failed: %s", err)
+		}
+		got := new(strings.Builder)
+		n, err = NewReader(buf, []byte(password), segmentSize).WriteTo(got)
+		if err != nil {
+			t.Fatalf("Reader.WriteTo failed: %s", err)
+		}
+		if n != int64(len(msg)) {
+			t.Errorf("Reader.WriteTo returned %d bytes, want %d", n, len(msg))
+		}
+		if got.String() != msg {
+			t.Errorf("Message failed to round-trip, got %q, want %q", got, msg)
+		}
+	})
+}