Update some files

Author: itsubaki

dataset/mnist/mnist_test.go

@@ -1,7 +1,10 @@
 package mnist_test
 
 import (
+	"bytes"
+	"compress/gzip"
 	"fmt"
+	"os"
 	"testing"
 
 	"github.com/itsubaki/neu/dataset/mnist"
@@ -122,3 +125,49 @@ func TestMust(t *testing.T) {
 	mnist.Must(nil, nil, fmt.Errorf("something went wrong"))
 	t.Fail()
 }
+
+func TestLoadImage(t *testing.T) {
+	invalid := []byte{0x00, 0x08, 0x03, 0x00, 0x00, 0x00, 0x00, 0x00}
+	file := "invalid.gz"
+
+	buf := new(bytes.Buffer)
+	w := gzip.NewWriter(buf)
+	if _, err := w.Write(invalid); err != nil {
+		t.Fatalf("write gzip data: %v", err)
+	}
+	w.Close()
+
+	if err := os.WriteFile(file, buf.Bytes(), 0644); err != nil {
+		t.Fatalf("write invalid file: %v", err)
+	}
+	defer os.Remove(file)
+
+	if _, err := mnist.LoadImage(file); err != nil {
+		return
+	}
+
+	t.Fatal("unexpected")
+}
+
+func TestLoadLabel(t *testing.T) {
+	invalid := []byte{0x00, 0x08, 0x01, 0x00, 0x00, 0x00}
+	file := "invalid.gz"
+
+	buf := new(bytes.Buffer)
+	w := gzip.NewWriter(buf)
+	if _, err := w.Write(invalid); err != nil {
+		t.Fatalf("write gzip data: %v", err)
+	}
+	w.Close()
+
+	if err := os.WriteFile(file, buf.Bytes(), 0644); err != nil {
+		t.Fatalf("write invalid file: %v", err)
+	}
+	defer os.Remove(file)
+
+	if _, err := mnist.LoadLabel(file); err != nil {
+		return
+	}
+
+	t.Fatal("unexpected")
+}

math/rand/crypto.go

@@ -5,6 +5,8 @@ import (
 	"fmt"
 )
 
+var RandRead = rand.Read
+
 func Must[T any](a T, err error) T {
 	if err != nil {
 		panic(err)
@@ -19,7 +21,7 @@ func MustRead() [32]byte {
 
 func Read() ([32]byte, error) {
 	var p [32]byte
-	if _, err := rand.Read(p[:]); err != nil {
+	if _, err := RandRead(p[:]); err != nil {
 		return [32]byte{}, fmt.Errorf("read: %v", err)
 	}
 

math/rand/crypto_test.go

@@ -2,27 +2,31 @@ package rand_test
 
 import (
 	crand "crypto/rand"
+	"errors"
 	"fmt"
 	randv2 "math/rand/v2"
-	"strings"
 	"testing"
 
 	"github.com/itsubaki/neu/math/rand"
 )
 
+var ErrSomtingWentWrong = errors.New("something went wrong")
+
 func ExampleRead() {
-	reader := crand.Reader
 	defer func() {
-		crand.Reader = reader
+		rand.RandRead = crand.Read
 	}()
 
-	crand.Reader = strings.NewReader("io.Reader stream to be read\n")
+	rand.RandRead = func(b []byte) (int, error) {
+		return 0, ErrSomtingWentWrong
+	}
+
 	if _, err := rand.Read(); err != nil {
 		fmt.Println(err)
 	}
 
 	// Output:
-	// read: unexpected EOF
+	// read: something went wrong
 }
 
 func TestMustRead(t *testing.T) {