From 522c6dcbfa4de56eb295a6d8103c466e86da0490 Mon Sep 17 00:00:00 2001
From: ixje <git@erikvandenbrink.com>
Date: Fri, 29 Sep 2023 09:47:44 +0200
Subject: [PATCH] vm: allow pushing empty strings (#284)

---
 neo3/vm.py       |  2 --
 tests/test_vm.py | 10 +++++-----
 2 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/neo3/vm.py b/neo3/vm.py
index 3d8cab45..8ac42152 100644
--- a/neo3/vm.py
+++ b/neo3/vm.py
@@ -357,8 +357,6 @@ def emit_push(self, value) -> ScriptBuilder:
                 raise ValueError("Input number exceeds maximum data size of 32 bytes")
         elif isinstance(value, (bytes, bytearray)):
             len_value = len(value)
-            if len_value == 0:
-                raise ValueError("Cannot push zero sized data")
             if len_value > 0xFFFFFFFF:
                 raise ValueError(
                     f"Value is too long {len_value}. Maximum allowed length is 0xFFFF_FFFF"
diff --git a/tests/test_vm.py b/tests/test_vm.py
index 38010a14..61c59e74 100644
--- a/tests/test_vm.py
+++ b/tests/test_vm.py
@@ -40,6 +40,11 @@ def test_emit_push_strings(self):
         expected = "0c0cd0bfd180d0b8d0b2d0b5d182"
         self.assertEqual(expected, sb.to_array().hex())
 
+        sb = vm.ScriptBuilder()
+        sb.emit_push("")
+        expected = "0c00"
+        self.assertEqual(expected, sb.to_array().hex())
+
     def test_emit_push_uint(self):
         sb = vm.ScriptBuilder()
         sb.emit_push(
@@ -126,11 +131,6 @@ def test_emit_push_bytes(self):
         expected_header = bytes.fromhex("0e01000100")
         self.assertEqual(expected_header + data, sb.to_array())
 
-        sb = vm.ScriptBuilder()
-        with self.assertRaises(ValueError) as context:
-            sb.emit_push(b"")
-        self.assertEqual("Cannot push zero sized data", str(context.exception))
-
         # too slow
         # data = b'\x01' * (0xFFFFFFFF + 1)
         # sb = vm.ScriptBuilder()