Create diskslice_test.go

diskslice/diskslice_test.go

@@ -0,0 +1,114 @@
+package diskslice
+
+import (
+	"bytes"
+	"context"
+	"io"
+	"io/ioutil"
+	"math/rand"
+	"os"
+	"path"
+	"strconv"
+	"testing"
+	"time"
+
+	"github.com/pierrec/lz4"
+)
+
+const letters = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
+
+func randStringBytes() []byte {
+	b := make([]byte, 1000)
+	for i := range b {
+		b[i] = letters[rand.Intn(len(letters))]
+	}
+	return b
+}
+
+func TestDiskList(t *testing.T) {
+	ri := func(src io.Reader) io.ReadCloser {
+		return ioutil.NopCloser(lz4.NewReader(src))
+	}
+	wi := func(dst io.Writer) io.WriteCloser {
+		return lz4.NewWriter(dst)
+	}
+
+	cases := []struct {
+		desc     string
+		roptions []ReadOption
+		woptions []WriteOption
+	}{
+		{"No options", nil, nil},
+		{
+			"Compression",
+			[]ReadOption{ReadIntercept(ri)},
+			[]WriteOption{WriteIntercept(wi)},
+		},
+		{"Caching", []ReadOption{CacheIndex()}, nil},
+	}
+
+	for _, c := range cases {
+		t.Run(
+			c.desc,
+			func(t *testing.T) {
+				SubDiskList(t, c.roptions, c.woptions)
+			},
+		)
+	}
+}
+
+func SubDiskList(t *testing.T, readOptions []ReadOption, writeOptions []WriteOption) {
+	p := path.Join(os.TempDir(), nextSuffix())
+	w, err := New(p, writeOptions...)
+	if err != nil {
+		panic(err)
+	}
+	defer os.Remove(p)
+
+	data := make([][]byte, 1000)
+	for i := 0; i < 1000; i++ {
+		v := randStringBytes()
+
+		if err := w.Write(v); err != nil {
+			t.Fatalf("error writing:\nkey:%q\nvalue:%q\n", i, v)
+		}
+		data[i] = v
+	}
+
+	if err := w.Close(); err != nil {
+		t.Fatalf("error closing the Writer: %q", err)
+	}
+
+	r, err := Open(p, readOptions...)
+	if err != nil {
+		t.Fatalf("error opening diskmap %q", err)
+	}
+
+	for i, v := range data {
+		val, err := r.Read(i)
+		if err != nil {
+			t.Fatalf("an index(%d)/value pair was lost: %q", i, err)
+		}
+
+		if bytes.Compare(val, v) != 0 {
+			t.Fatalf("a value(@%d) was not correctly stored, got %s, want %s", i, string(val), string(v))
+		}
+	}
+
+	for value := range r.Range(context.Background(), 0, -1) {
+		if value.Err != nil {
+			t.Fatalf("got unexpected error in Range(): %s", value.Err)
+		}
+
+		if bytes.Compare(value.Value, data[value.Index]) != 0 {
+			t.Fatalf("during Range(): a value(@%d) was not correctly stored, got %s, want %s", value.Index, string(value.Value), string(data[value.Index]))
+		}
+	}
+}
+
+func nextSuffix() string {
+	r := uint32(time.Now().UnixNano() + int64(os.Getpid()))
+
+	r = r*1664525 + 1013904223 // constants from Numerical Recipes
+	return strconv.Itoa(int(1e9 + r%1e9))[1:]
+}