chunks: add randomized test

chunks/chunk_test.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"io"
 	"math/rand"
+	"reflect"
 	"testing"
 
 	"github.com/stretchr/testify/require"
@@ -14,6 +15,58 @@ type pair struct {
 	v float64
 }
 
+func TestChunk(t *testing.T) {
+	for enc, nc := range map[Encoding]func(sz int) Chunk{
+		EncXOR: func(sz int) Chunk { return NewXORChunk(sz) },
+	} {
+		t.Run(fmt.Sprintf("%s", enc), func(t *testing.T) {
+			for range make([]struct{}, 10000) {
+				c := nc(rand.Intn(512))
+				testChunk(t, c)
+			}
+		})
+	}
+}
+
+func testChunk(t *testing.T, c Chunk) {
+	app, err := c.Appender()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var exp []pair
+	var (
+		ts = int64(1234123324)
+		v  = 1243535.123
+	)
+	for {
+		ts += int64(rand.Intn(10000) + 1)
+		v = rand.Float64()
+
+		err := app.Append(ts, v)
+		if err != nil {
+			if err == ErrChunkFull {
+				break
+			}
+			t.Fatal(err)
+		}
+		exp = append(exp, pair{t: ts, v: v})
+	}
+
+	it := c.Iterator()
+	var res []pair
+	for it.Next() {
+		ts, v := it.Values()
+		res = append(res, pair{t: ts, v: v})
+	}
+	if it.Err() != nil {
+		t.Fatal(it.Err())
+	}
+	if !reflect.DeepEqual(exp, res) {
+		t.Fatalf("unexpected result\n\ngot: %v\n\nexp: %v", res, exp)
+	}
+}
+
 func benchmarkIterator(b *testing.B, newChunk func(int) Chunk) {
 	var (
 		t = int64(1234123324)