Testing traversal from head

cmd/chron-cli/main.go

@@ -84,7 +84,7 @@ func main() {
 		return
 	}
 
-	for i := range 500 {
+	for i := range 1000000 {
 		data := fmt.Sprintf("test%d", i)
 
 		err = ledger.Append(ctx, []byte(data))
@@ -107,34 +107,37 @@ func main() {
 		return entries[i].Timestamp.Before(entries[j].Timestamp)
 	})
 
-	fmt.Println("Entries:")
-	if len(entries) == 0 {
-		fmt.Println("  (none)")
-	} else {
-		for _, e := range entries {
-			fmt.Printf("  ts=%d id=%s prev=%s payload=%q\n",
-				e.Timestamp.UnixNano(),
-				hex.EncodeToString(e.EntryID[:]),
-				hex.EncodeToString(e.Previous[:]),
-				e.Payload,
-			)
-		}
+	headID, ok, err := referenceStore.Get(ctx, "HEAD")
+	if err != nil {
+		fmt.Println("get HEAD:", err)
+		return
+	}
+	if !ok {
+		fmt.Println("HEAD reference not set")
+		return
 	}
 
-	// ---- Print references (name -> EntryID hex) ----
-	names := make([]string, 0, len(referenceStore.references))
-	for name := range referenceStore.references {
-		names = append(names, name)
-	}
-	sort.Strings(names)
-
-	fmt.Println("References:")
-	if len(names) == 0 {
-		fmt.Println("  (none)")
-	} else {
-		for _, name := range names {
-			id := referenceStore.references[name]
-			fmt.Printf("  %s -> %s\n", name, hex.EncodeToString(id[:]))
+	isZero32 := func(b [32]byte) bool {
+		for _, v := range b {
+			if v != 0 {
+				return false
+			}
 		}
+		return true
+	}
+
+	curID := headID
+	for {
+		ent, err := entryStore.Load(ctx, curID)
+		if err != nil {
+			return
+		}
+
+		if isZero32(ent.Previous) {
+			break
+		}
+
+		// Follow the linked list backwards
+		curID = core.EntryID(ent.Previous)
 	}
 }