neo-go/pkg/vm/vm_test.go
dauTT 24cd21bd8c VM:Implement THROW opcode (#219)
[VM]

- Changed vmstate from HALT to FAULT in Sub opcode
- Implemented THROW opcode + tests
- Renamed TestSimpleRun test to TestThrowIfNot
2019-03-26 21:19:41 +00:00

146 lines
3.4 KiB
Go

package vm
import (
"fmt"
"testing"
"github.com/CityOfZion/neo-go/pkg/vm/stack"
"github.com/stretchr/testify/assert"
)
func TestPushAdd(t *testing.T) {
builder := stack.NewBuilder()
// PUSH TWO NUMBER
// ADD THEM TOGETHER
builder.EmitInt(20).EmitInt(34).EmitOpcode(stack.ADD)
// Pass program to VM
vm := NewVM(builder.Bytes())
// Execute first OPCODE
// Should be PUSH(20)
state, err := vm.step()
assert.Equal(t, NONE, int(state))
assert.Nil(t, err)
// We should have the number 20 on stack
ok := peekTopEStackIsValue(t, vm, 20)
assert.True(t, ok)
// Excute second OPCODE
// Should be PUSH(34)
state, err = vm.step()
assert.Equal(t, NONE, int(state))
assert.Nil(t, err)
// We should have the number 34 at the top of the stack
ok = peekTopEStackIsValue(t, vm, 34)
assert.True(t, ok)
// Excute third OPCODE
// Should Add both values on the stack
state, err = vm.step()
assert.Equal(t, NONE, int(state))
assert.Nil(t, err)
// We should now have one value on the stack
//It should be equal to 20+34 = 54
ok = EstackLen(t, vm, 1)
assert.True(t, ok)
ok = peekTopEStackIsValue(t, vm, 54)
assert.True(t, ok)
// If we try to step again, we should get a nil error and HALT
// because we have gone over the instruction pointer
// error is nil because when there are nomore instructions, the vm
// will add a RET opcode and return
state, err = vm.step()
assert.Equal(t, HALT, int(state))
assert.Nil(t, err)
}
func TestThrowIfNot(t *testing.T) {
// Program pushes 20 and 34 to the stack
// Adds them together
// pushes 54 to the stack
// Checks if result of addition and 54 are equal
// Faults if not
// Push(20)
// Push(34)
// Add
// Push(54)
// Equal
//THROWIFNOT
builder := stack.NewBuilder()
builder.EmitInt(20).EmitInt(34).EmitOpcode(stack.ADD)
builder.EmitInt(54).EmitOpcode(stack.EQUAL).EmitOpcode(stack.THROWIFNOT)
// Pass program to VM
vm := NewVM(builder.Bytes())
// Runs vm with program
_, err := vm.Run()
assert.Nil(t, err)
// ResultStack should be nil
assert.Equal(t, -1, vm.ResultStack.Len())
// InvocationStack should be empty
assert.Equal(t, 0, vm.InvocationStack.Len())
}
func TestThrow(t *testing.T) {
// Program pushes 20 to the stack
// exits with an error
// Push(20)
// THROW
builder := stack.NewBuilder()
builder.EmitInt(20).EmitOpcode(stack.THROW)
// Pass program to VM
vm := NewVM(builder.Bytes())
// Runs vm with program
_, err := vm.Run()
assert.NotNil(t, err)
ctx, err := vm.InvocationStack.CurrentContext()
assert.Equal(t, nil, err)
assert.Equal(t, 1, ctx.Estack.Len())
assert.Equal(t, -1, ctx.Astack.Len())
}
// returns true if the value at the top of the evaluation stack is a integer
// and equals the value passed in
func peekTopEStackIsValue(t *testing.T, vm *VM, value int64) bool {
item := peakTopEstack(t, vm)
integer, err := item.Integer()
assert.Nil(t, err)
return value == integer.Value().Int64()
}
// peaks the stack item on the top of the evaluation stack
// if the current context and returns it
func peakTopEstack(t *testing.T, vm *VM) stack.Item {
ctx, err := vm.InvocationStack.CurrentContext()
fmt.Println(err)
assert.Nil(t, err)
item, err := ctx.Estack.Peek(0)
assert.Nil(t, err)
return item
}
// returns true if the total number of items on the evaluation stack is equal to value
func EstackLen(t *testing.T, vm *VM, value int) bool {
ctx, err := vm.InvocationStack.CurrentContext()
assert.Nil(t, err)
return value == ctx.Estack.Len()
}