diff --git a/tests/functional/builtins/codegen/test_unary.py b/tests/functional/builtins/codegen/test_unary.py
index da3823edfe..826bbe9d0c 100644
--- a/tests/functional/builtins/codegen/test_unary.py
+++ b/tests/functional/builtins/codegen/test_unary.py
@@ -68,16 +68,11 @@ def bar() -> decimal:
 
 def test_negation_int128(get_contract):
     code = """
-a: constant(int128) = -2**127
-
-@external
-def foo() -> int128:
-    return -2**127
+a: constant(int128) = min_value(int128)
 
 @external
 def bar() -> int128:
     return -(a+1)
     """
     c = get_contract(code)
-    assert c.foo() == -(2**127)
     assert c.bar() == 2**127 - 1
diff --git a/tests/functional/builtins/folding/test_abs.py b/tests/functional/builtins/folding/test_abs.py
index 1c919d7826..629d5baf52 100644
--- a/tests/functional/builtins/folding/test_abs.py
+++ b/tests/functional/builtins/folding/test_abs.py
@@ -54,7 +54,7 @@ def test_abs_lower_bound_folded(get_contract, assert_tx_failed):
     source = """
 @external
 def foo() -> int256:
-    return abs(-2**255)
+    return abs(min_value(int256))
     """
     with pytest.raises(OverflowException):
         get_contract(source)
diff --git a/tests/functional/codegen/calling_convention/test_external_contract_calls.py b/tests/functional/codegen/calling_convention/test_external_contract_calls.py
index 12fcde2f4f..935c7b74fc 100644
--- a/tests/functional/codegen/calling_convention/test_external_contract_calls.py
+++ b/tests/functional/codegen/calling_convention/test_external_contract_calls.py
@@ -380,7 +380,7 @@ def test_int128_too_long(get_contract, assert_tx_failed):
     contract_1 = """
 @external
 def foo() -> int256:
-    return (2**255)-1
+    return max_value(int256)
     """
 
     c = get_contract(contract_1)
diff --git a/tests/functional/syntax/test_unary.py b/tests/functional/syntax/test_unary.py
new file mode 100644
index 0000000000..2b69f90023
--- /dev/null
+++ b/tests/functional/syntax/test_unary.py
@@ -0,0 +1,22 @@
+import pytest
+
+from vyper.compiler import compile_code
+from vyper.exceptions import InvalidType, TypeMismatch
+
+
+fail_list = [
+    (
+        """
+@external
+def foo() -> int128:
+    return -2**127
+    """,
+        InvalidType,
+    ),
+]
+
+
+@pytest.mark.parametrize("code,exc", fail_list)
+def test_unary_fail(code, exc):
+    with pytest.raises(exc):
+        compile_code(code)