diff --git a/tests/micropython/viper_error.py b/tests/micropython/viper_error.py
index 116bd4ea03..8472572854 100644
--- a/tests/micropython/viper_error.py
+++ b/tests/micropython/viper_error.py
@@ -3,13 +3,19 @@
 def test(code):
     try:
         exec(code)
-    except (SyntaxError, ViperTypeError) as e:
+    except (SyntaxError, ViperTypeError, NotImplementedError) as e:
         print(repr(e))
 
 # viper: annotations must be identifiers
 test("@micropython.viper\ndef f(a:1): pass")
 test("@micropython.viper\ndef f() -> 1: pass")
 
+# unknown type
+test("@micropython.viper\ndef f(x:unknown_type): pass")
+
+# too many arguments
+test("@micropython.viper\ndef f(a, b, c, d, e): pass")
+
 # local used before type known
 test("""
 @micropython.viper
@@ -49,6 +55,9 @@ test("@micropython.viper\ndef f(): 1[x]")
 # can't store
 test("@micropython.viper\ndef f(): 1[0] = 1")
 test("@micropython.viper\ndef f(): 1[x] = 1")
+test("@micropython.viper\ndef f(x:int): x[0] = x")
+test("@micropython.viper\ndef f(x:ptr32): x[0] = None")
+test("@micropython.viper\ndef f(x:ptr32): x[x] = None")
 
 # must raise an object
 test("@micropython.viper\ndef f(): raise 1")
@@ -57,3 +66,16 @@ test("@micropython.viper\ndef f(): raise 1")
 test("@micropython.viper\ndef f(x:int): +x")
 test("@micropython.viper\ndef f(x:int): -x")
 test("@micropython.viper\ndef f(x:int): ~x")
+
+# binary op not implemented
+test("@micropython.viper\ndef f(x:int): res = x in x")
+
+# yield (from) not implemented
+test("@micropython.viper\ndef f(): yield")
+test("@micropython.viper\ndef f(): yield from f")
+
+# passing a ptr to a Python function not implemented
+test("@micropython.viper\ndef f(): print(ptr(1))")
+
+# cast of a casting identifier not implemented
+test("@micropython.viper\ndef f(): int(int)")
diff --git a/tests/micropython/viper_error.py.exp b/tests/micropython/viper_error.py.exp
index 1afcd4bdbe..96be5a5902 100644
--- a/tests/micropython/viper_error.py.exp
+++ b/tests/micropython/viper_error.py.exp
@@ -1,5 +1,7 @@
 SyntaxError('parameter annotation must be an identifier',)
 SyntaxError('return annotation must be an identifier',)
+ViperTypeError("unknown type 'unknown_type'",)
+ViperTypeError("Viper functions don't currently support more than 4 arguments",)
 ViperTypeError("local 'x' used before type known",)
 ViperTypeError("local 'x' has type 'int' but source is 'object'",)
 ViperTypeError("can't implicitly convert 'ptr' to 'bool'",)
@@ -9,7 +11,15 @@ ViperTypeError("can't load from 'int'",)
 ViperTypeError("can't load from 'int'",)
 ViperTypeError("can't store to 'int'",)
 ViperTypeError("can't store to 'int'",)
+ViperTypeError("can't store to 'int'",)
+ViperTypeError("can't store 'None'",)
+ViperTypeError("can't store 'None'",)
 ViperTypeError('must raise an object',)
 ViperTypeError('unary op __pos__ not implemented',)
 ViperTypeError('unary op __neg__ not implemented',)
 ViperTypeError('unary op __invert__ not implemented',)
+ViperTypeError('binary op __contains__ not implemented',)
+NotImplementedError('native yield',)
+NotImplementedError('native yield from',)
+NotImplementedError('conversion to object',)
+NotImplementedError('casting',)