more builtins; support params, state vars in loop iterators

slither/core/declarations/solidity_variables.py

@@ -16,6 +16,7 @@ SOLIDITY_VARIABLES = {
     "tx": "",
     "block": "",
     "super": "",
+    "chain": "",
 }
 
 SOLIDITY_VARIABLES_COMPOSED = {
@@ -86,7 +87,7 @@ SOLIDITY_FUNCTIONS: Dict[str, List[str]] = {
     "create_from_blueprint()":[],
     "empty()":[],
     "convert()":[], # TODO make type conversion
-    "len()":[], 
+    "len()":["uint256"],
     "method_id()":[],
     "unsafe_sub()": [],
     "unsafe_add()": [],
@@ -97,7 +98,15 @@ SOLIDITY_FUNCTIONS: Dict[str, List[str]] = {
     "min_value()":[],
     "concat()":[],
     "ecrecover()":[],
-    "isqrt()":[]
+    "isqrt()":[],
+    "range()":[],
+    "min()":[],
+    "max()":[],
+    "shift()":[],
+    "abs()":[],
+    "raw_call()":[],
+    "_abi_encode()":[],
+    "slice()":[],
 }
 
 

slither/vyper_parsing/declarations/contract.py

@@ -85,7 +85,7 @@ class ContractVyper:
                     self._contract.file_scope.contracts[contract.name] = contract
 
             elif isinstance(node, InterfaceDef):
-                # TODO This needs to be done lazily as interfaces can refer to constant state variables
+                # This needs to be done lazily as interfaces can refer to constant state variables
                 contract = Contract(self._contract.compilation_unit, self._contract.file_scope)
                 contract.set_offset(node.src, self._contract.compilation_unit)
                 contract.is_interface = True
@@ -158,7 +158,7 @@ class ContractVyper:
             func.set_contract(self._contract)
             func.set_contract_declarer(self._contract)
 
-            func_parser = FunctionVyper(func, function)
+            func_parser = FunctionVyper(func, function, self)
             self._contract.add_function(func)
             self._functions_parser.append(func_parser)
 

slither/vyper_parsing/declarations/function.py

@@ -30,6 +30,7 @@ class FunctionVyper:
         self,
         function: Function,
         function_data: Dict,
+        contract_parser: "ContractVyper",
     ) -> None:
         self._node_to_NodeVyper: Dict[Node, NodeVyper] = {}
 
@@ -40,6 +41,7 @@ class FunctionVyper:
         self._function.id = function_data.node_id
 
         self._local_variables_parser: List = []
+        self._contract_parser = contract_parser
 
         for decorator in function_data.decorators:
             if not hasattr(decorator, "id"):
@@ -255,18 +257,28 @@ class FunctionVyper:
                         new_node.add_unparsed_expression(counter_var.value)
                         new_node.underlying_node.add_variable_declaration(local_var)
 
-                        if isinstance(expr.iter, Name):
+                        if isinstance(expr.iter, (Attribute,Name)):
+                            # HACK  
+                            # The loop variable is not annotated so we infer its type by looking at the type of the iterator
+                            if isinstance(expr.iter, Attribute): # state
+                                iter_expr = expr.iter
+                                loop_iterator = list(filter(lambda x: x._variable.name == iter_expr.attr,  self._contract_parser._variables_parser))[0]
+
+                            else: # local
+                                iter_expr = expr.iter
+                                loop_iterator = list(filter(lambda x: x._variable.name == iter_expr.id, self._local_variables_parser))[0]
+
                             # TODO use expr.src instead of -1:-1:1?
-                            cond_expr = Compare("-1:-1:-1", -1, left=Name("-1:-1:-1", -1, "counter_var"), op="<=", right=Call("-1:-1:-1", -1, func=Name("-1:-1:-1", -1, "len"), args=[expr.iter], keywords=[], keyword=None))
+                            cond_expr = Compare("-1:-1:-1", -1, left=Name("-1:-1:-1", -1, "counter_var"), op="<=", right=Call("-1:-1:-1", -1, func=Name("-1:-1:-1", -1, "len"), args=[iter_expr], keywords=[], keyword=None))
                             node_condition = self._new_node(NodeType.IFLOOP, expr.src, scope)
                             node_condition.add_unparsed_expression(cond_expr)
 
-                            # HACK  
-                            # The loop variable is not annotated so we infer its type by looking at the type of the iterator
-                            loop_iterator = list(filter(lambda x: x._variable.name == expr.iter.id, self._local_variables_parser))[0]
-                            # Assumes `Subscript`
                             # TODO this should go in the body of the loop: expr.body.insert(0, ...)
-                            loop_var_annotation = loop_iterator._elem_to_parse.slice.value.elements[0]
+                            if loop_iterator._elem_to_parse.value.id == "DynArray":
+                                loop_var_annotation = loop_iterator._elem_to_parse.slice.value.elements[0]
+                            else:
+                                loop_var_annotation = loop_iterator._elem_to_parse.value
+
                             value = Subscript("-1:-1:-1", -1, value=Name("-1:-1:-1", -1, loop_iterator._variable.name), slice=Index("-1:-1:-1", -1, value=Name("-1:-1:-1", -1, "counter_var")))
                             loop_var = AnnAssign(expr.target.src, expr.target.node_id, target=expr.target, annotation=loop_var_annotation, value=value)
                             local_var = LocalVariable()

slither/vyper_parsing/expressions/expression_parsing.py

@@ -282,7 +282,10 @@ def parse_expression(expression: Dict, caller_context) -> "Expression":
         called = parse_expression(expression.func, caller_context)
 
         if isinstance(called, Identifier) and isinstance(called.value, SolidityFunction):
-            if called.value.name == "convert()":
+            if called.value.name == "empty()":
+                type_to = parse_type(expression.args[0], caller_context)
+                return CallExpression(called, [], str(type_to))
+            elif called.value.name == "convert()":
                 arg = parse_expression(expression.args[0], caller_context) 
                 type_to = parse_type(expression.args[1], caller_context)
                 return TypeConversion(arg, type_to)
@@ -294,9 +297,8 @@ def parse_expression(expression: Dict, caller_context) -> "Expression":
             elif called.value.name==  "max_value()":
                 type_to = parse_type(expression.args[0], caller_context)
                 member_type =  str(type_to)
-                x = MemberAccess("max", member_type, CallExpression(Identifier(SolidityFunction("type()")), [ElementaryTypeNameExpression(type_to)], member_type))
-                print(x)
-                return x
+                # TODO return Literal
+                return MemberAccess("max", member_type, CallExpression(Identifier(SolidityFunction("type()")), [ElementaryTypeNameExpression(type_to)], member_type))
 
 
         if expression.args and isinstance(expression.args[0], VyDict):
@@ -320,7 +322,10 @@ def parse_expression(expression: Dict, caller_context) -> "Expression":
             
             else:
                 rets = ["tuple()"]
-            
+        elif isinstance(called, MemberAccess) and called.type is not None:
+            # (recover_type_2) Propagate the type collected to the `CallExpression`
+            # see recover_type_1
+            rets = called.type
         else:
             rets = ["tuple()"]
         
@@ -330,7 +335,8 @@ def parse_expression(expression: Dict, caller_context) -> "Expression":
             return str(x.type)
 
         type_str = get_type_str(rets[0]) if len(rets) == 1 else f"tuple({','.join(map(get_type_str, rets))})"
-
+        print(CallExpression(called, arguments, type_str))
+        print(type_str)
         return CallExpression(called, arguments, type_str)
     
     if isinstance(expression, Attribute):
@@ -352,8 +358,25 @@ def parse_expression(expression: Dict, caller_context) -> "Expression":
 
         else:
             expr = parse_expression(expression.value, caller_context)
-
-            member_access = MemberAccess(member_name, None, expr)
+            member_name_ret_type = None
+            # (recover_type_1) This may be a call to an interface and we don't have the return types,
+            # so we see if there's a function identifier with `member_name` and propagate the type to 
+            # its enclosing `CallExpression`
+            # try: TODO this is using the wrong caller_context and needs to be interface instead of self namespace
+            #     var, was_created = find_variable(member_name, caller_context)
+            #     if isinstance(var, Function):
+            #         rets = var.returns
+            #         def get_type_str(x):
+            #             if isinstance(x, str):
+            #                 return x
+            #             return str(x.type)
+
+            #         type_str = get_type_str(rets[0]) if len(rets) == 1 else f"tuple({','.join(map(get_type_str, rets))})"
+            #         member_name_ret_type = type_str
+            # except:
+            #     pass
+
+            member_access = MemberAccess(member_name, member_name_ret_type, expr)
 
         return member_access
 
@@ -373,9 +396,9 @@ def parse_expression(expression: Dict, caller_context) -> "Expression":
         rhs = parse_expression(expression.value, caller_context)
 
         op = AssignmentOperationType.get_type(expression.op)
-        return BinaryOperation(lhs, rhs, op)
+        return AssignmentOperation(lhs, rhs, op, None)
 
-    if isinstance(expression, Tuple):
+    if isinstance(expression, (Tuple, VyList)):
         tuple_vars = [parse_expression(x, caller_context) for x in expression.elements]
         return TupleExpression(tuple_vars)
     

slither/vyper_parsing/variables/local_variable.py

@@ -9,13 +9,17 @@ class LocalVariableVyper:
     def __init__(self, variable: LocalVariable, variable_data: Union[Arg, Name]) -> None:
         self._variable: LocalVariable = variable
 
-        if isinstance(variable_data, (Arg, )):
+        if isinstance(variable_data, Arg):
             self._variable.name = variable_data.arg
             self._elem_to_parse = variable_data.annotation
-        elif isinstance(variable_data, (AnnAssign, )):
+        elif isinstance(variable_data, AnnAssign):
             self._variable.name = variable_data.target.id
             self._elem_to_parse = variable_data.annotation
+        elif isinstance(variable_data, Name):
+            self._variable.name = variable_data.id
+            self._elem_to_parse = variable_data
         else:
+            # param Subscript
             self._variable.name = ""
             self._elem_to_parse = variable_data