Merge pull request #2051 from crytic/dev-fix-enum-max-min

Fix enum.max/min when enum in other contract

slither/visitors/slithir/expression_to_slithir.py

@@ -455,6 +455,7 @@ class ExpressionToSlithIR(ExpressionVisitor):
         # Look for type(X).max / min
         # Because we looked at the AST structure, we need to look into the nested expression
         # Hopefully this is always on a direct sub field, and there is no weird construction
+        # pylint: disable=too-many-nested-blocks
         if isinstance(expression.expression, CallExpression) and expression.member_name in [
             "min",
             "max",
@@ -474,10 +475,22 @@ class ExpressionToSlithIR(ExpressionVisitor):
                         constant_type = type_found
                     else:
                         # type(enum).max/min
-                        assert isinstance(type_expression_found, Identifier)
-                        type_found_in_expression = type_expression_found.value
-                        assert isinstance(type_found_in_expression, (EnumContract, EnumTopLevel))
-                        type_found = UserDefinedType(type_found_in_expression)
+                        # Case when enum is in another contract e.g. type(C.E).max
+                        if isinstance(type_expression_found, MemberAccess):
+                            contract = type_expression_found.expression.value
+                            assert isinstance(contract, Contract)
+                            for enum in contract.enums:
+                                if enum.name == type_expression_found.member_name:
+                                    type_found_in_expression = enum
+                                    type_found = UserDefinedType(enum)
+                                    break
+                        else:
+                            assert isinstance(type_expression_found, Identifier)
+                            type_found_in_expression = type_expression_found.value
+                            assert isinstance(
+                                type_found_in_expression, (EnumContract, EnumTopLevel)
+                            )
+                            type_found = UserDefinedType(type_found_in_expression)
                         constant_type = None
                         min_value = type_found_in_expression.min
                         max_value = type_found_in_expression.max
@@ -535,6 +548,10 @@ class ExpressionToSlithIR(ExpressionVisitor):
             if expression.member_name in expr.custom_errors_as_dict:
                 set_val(expression, expr.custom_errors_as_dict[expression.member_name])
                 return
+            # Lookup enums when in a different contract e.g. C.E
+            if str(expression) in expr.enums_as_dict:
+                set_val(expression, expr.enums_as_dict[str(expression)])
+                return
 
         val_ref = ReferenceVariable(self._node)
         member = Member(expr, Constant(expression.member_name), val_ref)

tests/e2e/solc_parsing/test_ast_parsing.py

@@ -460,6 +460,7 @@ ALL_TESTS = [
     ),
     Test("user_defined_operators-0.8.19.sol", ["0.8.19"]),
     Test("type-aliases.sol", ["0.8.19"]),
+    Test("enum-max-min.sol", ["0.8.19"]),
 ]
 # create the output folder if needed
 try:

tests/e2e/solc_parsing/test_data/enum-max-min.sol

@@ -0,0 +1,37 @@
+
+library Q {
+    enum E {a}
+}
+
+contract Z {
+    enum E {a,b}
+}
+
+contract D {
+    enum E {a,b,c}
+
+    function a() public returns(uint){
+        return uint(type(E).max);
+    }
+
+    function b() public returns(uint){
+        return uint(type(Q.E).max);
+    }
+
+    function c() public returns(uint){
+        return uint(type(Z.E).max);
+    }
+
+    function d() public returns(uint){
+        return uint(type(E).min);
+    }
+
+    function e() public returns(uint){
+        return uint(type(Q.E).min);
+    }
+
+    function f() public returns(uint){
+        return uint(type(Z.E).min);
+    }
+
+}

tests/e2e/solc_parsing/test_data/expected/enum-max-min.sol-0.8.19-compact.json

@@ -0,0 +1,12 @@
+{
+  "Q": {},
+  "Z": {},
+  "D": {
+    "a()": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: RETURN 1\n\"];\n}\n",
+    "b()": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: RETURN 1\n\"];\n}\n",
+    "c()": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: RETURN 1\n\"];\n}\n",
+    "d()": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: RETURN 1\n\"];\n}\n",
+    "e()": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: RETURN 1\n\"];\n}\n",
+    "f()": "digraph{\n0[label=\"Node Type: ENTRY_POINT 0\n\"];\n0->1;\n1[label=\"Node Type: RETURN 1\n\"];\n}\n"
+  }
+}

tests/unit/slithir/test_data/enum_max_min.sol

@@ -0,0 +1,37 @@
+
+library Q {
+    enum E {a}
+}
+
+contract Z {
+    enum E {a,b}
+}
+
+contract D {
+    enum E {a,b,c}
+
+    function a() public returns(uint){
+        return uint(type(E).max);
+    }
+
+    function b() public returns(uint){
+        return uint(type(Q.E).max);
+    }
+
+    function c() public returns(uint){
+        return uint(type(Z.E).max);
+    }
+
+    function d() public returns(uint){
+        return uint(type(E).min);
+    }
+
+    function e() public returns(uint){
+        return uint(type(Q.E).min);
+    }
+
+    function f() public returns(uint){
+        return uint(type(Z.E).min);
+    }
+
+}

tests/unit/slithir/test_enum.py

@@ -0,0 +1,67 @@
+from pathlib import Path
+from slither import Slither
+from slither.slithir.operations import Assignment
+from slither.slithir.variables import Constant
+
+TEST_DATA_DIR = Path(__file__).resolve().parent / "test_data"
+
+
+def test_enum_max_min(solc_binary_path) -> None:
+    solc_path = solc_binary_path("0.8.19")
+    slither = Slither(Path(TEST_DATA_DIR, "enum_max_min.sol").as_posix(), solc=solc_path)
+
+    contract = slither.get_contract_from_name("D")[0]
+
+    f = contract.get_function_from_full_name("a()")
+    # TMP_1(uint256) := 2(uint256)
+    assignment = f.slithir_operations[1]
+    assert (
+        isinstance(assignment, Assignment)
+        and isinstance(assignment.rvalue, Constant)
+        and assignment.rvalue.value == 2
+    )
+
+    f = contract.get_function_from_full_name("b()")
+    # TMP_4(uint256) := 0(uint256)
+    assignment = f.slithir_operations[1]
+    assert (
+        isinstance(assignment, Assignment)
+        and isinstance(assignment.rvalue, Constant)
+        and assignment.rvalue.value == 0
+    )
+
+    f = contract.get_function_from_full_name("c()")
+    # TMP_7(uint256) := 1(uint256)
+    assignment = f.slithir_operations[1]
+    assert (
+        isinstance(assignment, Assignment)
+        and isinstance(assignment.rvalue, Constant)
+        and assignment.rvalue.value == 1
+    )
+
+    f = contract.get_function_from_full_name("d()")
+    # TMP_10(uint256) := 0(uint256)
+    assignment = f.slithir_operations[1]
+    assert (
+        isinstance(assignment, Assignment)
+        and isinstance(assignment.rvalue, Constant)
+        and assignment.rvalue.value == 0
+    )
+
+    f = contract.get_function_from_full_name("e()")
+    # TMP_13(uint256) := 0(uint256)
+    assignment = f.slithir_operations[1]
+    assert (
+        isinstance(assignment, Assignment)
+        and isinstance(assignment.rvalue, Constant)
+        and assignment.rvalue.value == 0
+    )
+
+    f = contract.get_function_from_full_name("f()")
+    # TMP_16(uint256) := 0(uint256)
+    assignment = f.slithir_operations[1]
+    assert (
+        isinstance(assignment, Assignment)
+        and isinstance(assignment.rvalue, Constant)
+        and assignment.rvalue.value == 0
+    )