neo-go/pkg/vm/iterator_test.go
Evgenii Stratonikov 4b7b71ce25 vm: Add tests for iterator unwrap scripts
Check that is uses only 3 syscalls and also specify boundary behaviour.

Signed-off-by: Evgenii Stratonikov <fyfyrchik@runbox.com>
2023-12-29 10:50:43 +03:00

121 lines
3.9 KiB
Go

package vm
import (
"fmt"
"math/big"
"testing"
"github.com/nspcc-dev/neo-go/internal/random"
"github.com/nspcc-dev/neo-go/pkg/core/interop/interopnames"
"github.com/nspcc-dev/neo-go/pkg/smartcontract"
"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
"github.com/stretchr/testify/require"
)
type arrayIterator struct {
index int
values []stackitem.Item
}
func TestCreateCallAndUnwrapIteratorScript(t *testing.T) {
ctrHash := random.Uint160()
ctrMethod := "mymethod"
param := stackitem.NewBigInteger(big.NewInt(42))
const totalItems = 8
values := make([]stackitem.Item, totalItems)
for i := range values {
values[i] = stackitem.NewBigInteger(big.NewInt(int64(i)))
}
checkStack := func(t *testing.T, script []byte, index int, prefetch bool) {
v := load(script)
it := &arrayIterator{index: -1, values: values}
v.SyscallHandler = func(v *VM, id uint32) error {
switch id {
case interopnames.ToID([]byte(interopnames.SystemContractCall)):
require.Equal(t, ctrHash.BytesBE(), v.Estack().Pop().Value())
require.Equal(t, []byte(ctrMethod), v.Estack().Pop().Value())
require.Equal(t, big.NewInt(int64(callflag.All)), v.Estack().Pop().Value())
require.Equal(t, []stackitem.Item{param}, v.Estack().Pop().Value())
v.Estack().PushItem(stackitem.NewInterop(it))
case interopnames.ToID([]byte(interopnames.SystemIteratorNext)):
require.Equal(t, it, v.Estack().Pop().Value())
it.index++
v.Estack().PushVal(it.index < len(it.values))
case interopnames.ToID([]byte(interopnames.SystemIteratorValue)):
require.Equal(t, it, v.Estack().Pop().Value())
v.Estack().PushVal(it.values[it.index])
default:
return fmt.Errorf("unexpected syscall: %d", id)
}
return nil
}
require.NoError(t, v.Run())
if prefetch && index <= len(values) {
require.Equal(t, 2, v.Estack().Len())
it, ok := v.Estack().Pop().Interop().Value().(*arrayIterator)
require.True(t, ok)
require.Equal(t, index-1, it.index)
require.Equal(t, values[:index], v.Estack().Pop().Array())
return
}
if len(values) < index {
index = len(values)
}
require.Equal(t, 1, v.Estack().Len())
require.Equal(t, values[:index], v.Estack().Pop().Array())
}
t.Run("truncate", func(t *testing.T) {
t.Run("zero", func(t *testing.T) {
const index = 0
script, err := smartcontract.CreateCallAndUnwrapIteratorScript(ctrHash, ctrMethod, index, param)
require.NoError(t, err)
// The behaviour is a bit unexpected, but not a problem (why would anyone fetch 0 items).
// Let's have test, to make it obvious.
checkStack(t, script, index+1, false)
})
t.Run("all", func(t *testing.T) {
const index = totalItems + 1
script, err := smartcontract.CreateCallAndUnwrapIteratorScript(ctrHash, ctrMethod, index, param)
require.NoError(t, err)
checkStack(t, script, index, false)
})
t.Run("partial", func(t *testing.T) {
const index = totalItems / 2
script, err := smartcontract.CreateCallAndUnwrapIteratorScript(ctrHash, ctrMethod, index, param)
require.NoError(t, err)
checkStack(t, script, index, false)
})
})
t.Run("prefetch", func(t *testing.T) {
t.Run("zero", func(t *testing.T) {
const index = 0
script, err := smartcontract.CreateCallAndPrefetchIteratorScript(ctrHash, ctrMethod, index, param)
require.NoError(t, err)
checkStack(t, script, index+1, true)
})
t.Run("all", func(t *testing.T) {
const index = totalItems + 1 // +1 to test with iterator dropped
script, err := smartcontract.CreateCallAndPrefetchIteratorScript(ctrHash, ctrMethod, index, param)
require.NoError(t, err)
checkStack(t, script, index, true)
})
t.Run("partial", func(t *testing.T) {
const index = totalItems / 2
script, err := smartcontract.CreateCallAndPrefetchIteratorScript(ctrHash, ctrMethod, index, param)
require.NoError(t, err)
checkStack(t, script, index, true)
})
})
}