Fix parsing of constants

Fixes: #1376

slither/core/expressions/literal.py

@@ -2,6 +2,7 @@ from typing import Optional, Union, TYPE_CHECKING
 
 from slither.core.expressions.expression import Expression
 from slither.utils.arithmetic import convert_subdenomination
+from slither.utils.integer_conversion import convert_string_to_int
 
 if TYPE_CHECKING:
     from slither.core.solidity_types.type import Type
@@ -29,8 +30,7 @@ class Literal(Expression):
     def __str__(self):
         if self.subdenomination:
             return str(convert_subdenomination(self._value, self.subdenomination))
-        # be sure to handle any character
-        return str(self._value)
+        return str(convert_string_to_int(self._value))
 
     def __eq__(self, other):
         if not isinstance(other, Literal):

slither/core/solidity_types/array_type.py

@@ -53,7 +53,7 @@ class ArrayType(Type):
     def storage_size(self) -> Tuple[int, bool]:
         if self._length_value:
             elem_size, _ = self._type.storage_size
-            return elem_size * int(self._length_value.value), True
+            return elem_size * int(str(self._length_value)), True
         return 32, True
 
     def __str__(self):

slither/visitors/expression/constants_folding.py

@@ -1,3 +1,4 @@
+from decimal import Decimal, InvalidOperation
 from slither.core.expressions import BinaryOperationType, Literal, UnaryOperationType
 from slither.utils.integer_conversion import convert_string_to_int
 from slither.visitors.expression.expression import ExpressionVisitor
@@ -77,9 +78,9 @@ class ConstantFolding(ExpressionVisitor):
             raise NotConstant
 
     def _post_literal(self, expression):
-        if expression.value.isdigit():
-            set_val(expression, int(expression.value))
-        else:
+        try:
+            set_val(expression, Decimal(expression.value))
+        except InvalidOperation:
             raise NotConstant
 
     def _post_assignement_operation(self, expression):