From 09e197eaf3ec8e5e71395cd0ddc69a49f117dc43 Mon Sep 17 00:00:00 2001
From: Evgenii Stratonikov <evgeniy@nspcc.ru>
Date: Thu, 12 Sep 2019 11:42:27 +0300
Subject: [PATCH] vm: make PUSH0 create empty bytearray

Also make tests expect []byte{} instead of 0.
---
 pkg/vm/tests/binary_expr_test.go   | 10 +++++-----
 pkg/vm/tests/for_test.go           |  2 +-
 pkg/vm/tests/function_call_test.go |  2 +-
 pkg/vm/tests/if_test.go            |  6 +++---
 pkg/vm/tests/import_test.go        |  2 +-
 pkg/vm/tests/struct_test.go        |  4 ++--
 pkg/vm/vm.go                       |  2 +-
 7 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/pkg/vm/tests/binary_expr_test.go b/pkg/vm/tests/binary_expr_test.go
index 16e7509fb..fd24c2e37 100644
--- a/pkg/vm/tests/binary_expr_test.go
+++ b/pkg/vm/tests/binary_expr_test.go
@@ -26,7 +26,7 @@ var binaryExprTestCases = []testCase{
 			return x
 		}
 		`,
-		big.NewInt(0),
+		[]byte{},
 	},
 	{
 		"simple div",
@@ -86,7 +86,7 @@ var binaryExprTestCases = []testCase{
 			return 0
 		}
 		`,
-		big.NewInt(0),
+		[]byte{},
 	},
 	{
 		"compare equal strings with eql",
@@ -128,7 +128,7 @@ var binaryExprTestCases = []testCase{
 			return 0
 		}
 		`,
-		big.NewInt(0),
+		[]byte{},
 	},
 	{
 		"compare equal ints with eql",
@@ -156,7 +156,7 @@ var binaryExprTestCases = []testCase{
 			return 0
 		}
 		`,
-		big.NewInt(0),
+		[]byte{},
 	},
 	{
 		"compare not equal ints with eql",
@@ -170,7 +170,7 @@ var binaryExprTestCases = []testCase{
 			return 0
 		}
 		`,
-		big.NewInt(0),
+		[]byte{},
 	},
 	{
 		"compare not equal ints with neq",
diff --git a/pkg/vm/tests/for_test.go b/pkg/vm/tests/for_test.go
index 70b063ffe..2e3c15288 100644
--- a/pkg/vm/tests/for_test.go
+++ b/pkg/vm/tests/for_test.go
@@ -275,7 +275,7 @@ func TestIfUnaryInvert(t *testing.T) {
 			return 0
 		}
 	`
-	eval(t, src, big.NewInt(0))
+	eval(t, src, []byte{})
 }
 
 func TestAppendByte(t *testing.T) {
diff --git a/pkg/vm/tests/function_call_test.go b/pkg/vm/tests/function_call_test.go
index 442d703b4..1ac71b011 100644
--- a/pkg/vm/tests/function_call_test.go
+++ b/pkg/vm/tests/function_call_test.go
@@ -35,7 +35,7 @@ func TestNotAssignedFunctionCall(t *testing.T) {
 			return 0
 		}
 	`
-	eval(t, src, big.NewInt(0))
+	eval(t, src, []byte{})
 }
 
 func TestMultipleFunctionCalls(t *testing.T) {
diff --git a/pkg/vm/tests/if_test.go b/pkg/vm/tests/if_test.go
index 6e39d0ab6..c4483309e 100644
--- a/pkg/vm/tests/if_test.go
+++ b/pkg/vm/tests/if_test.go
@@ -30,7 +30,7 @@ func TestGT(t *testing.T) {
 			return 0
 		}
 	`
-	eval(t, src, big.NewInt(0))
+	eval(t, src, []byte{})
 }
 
 func TestGTE(t *testing.T) {
@@ -44,7 +44,7 @@ func TestGTE(t *testing.T) {
 			return 0
 		}
 	`
-	eval(t, src, big.NewInt(0))
+	eval(t, src, []byte{})
 }
 
 func TestLAND(t *testing.T) {
@@ -89,5 +89,5 @@ func TestNestedIF(t *testing.T) {
 			return 0
 		}
 	`
-	eval(t, src, big.NewInt(0))
+	eval(t, src, []byte{})
 }
diff --git a/pkg/vm/tests/import_test.go b/pkg/vm/tests/import_test.go
index c969ba71f..fb831fcef 100644
--- a/pkg/vm/tests/import_test.go
+++ b/pkg/vm/tests/import_test.go
@@ -32,7 +32,7 @@ func TestImportStruct(t *testing.T) {
 			 return b.Y
 	 	}
 	 `
-	eval(t, src, big.NewInt(0))
+	eval(t, src, []byte{})
 }
 
 func TestMultipleDirFileImport(t *testing.T) {
diff --git a/pkg/vm/tests/struct_test.go b/pkg/vm/tests/struct_test.go
index 759396889..e3de28f91 100644
--- a/pkg/vm/tests/struct_test.go
+++ b/pkg/vm/tests/struct_test.go
@@ -179,7 +179,7 @@ var structTestCases = []testCase{
 			return t.y
 		}
 		`,
-		big.NewInt(0),
+		[]byte{},
 	},
 	{
 		"test return struct from func",
@@ -209,7 +209,7 @@ var structTestCases = []testCase{
 			vm.NewBigIntegerItem(1),
 			vm.NewBigIntegerItem(2),
 			vm.NewByteArrayItem([]byte("hello")),
-			vm.NewBigIntegerItem(0),
+			vm.NewByteArrayItem([]byte{}),
 		},
 	},
 	{
diff --git a/pkg/vm/vm.go b/pkg/vm/vm.go
index 0587a6929..7e9c7bd05 100644
--- a/pkg/vm/vm.go
+++ b/pkg/vm/vm.go
@@ -257,7 +257,7 @@ func (v *VM) execute(ctx *Context, op Instruction) {
 		v.estack.PushVal(val)
 
 	case PUSH0:
-		v.estack.PushVal(0)
+		v.estack.PushVal([]byte{})
 
 	case PUSHDATA1:
 		n := ctx.readByte()