Add BYTES support to some expressions

lib/rule_engine/ast.py

@@ -42,6 +42,10 @@
 from .suggestions import suggest_symbol
 from .types import *
 
+def _assert_is_bytes(*values):
+	if not all(map(isinstance, values, [bytes])):
+		raise errors.EvaluationError('data type mismatch (not a bytes value)')
+
 def _assert_is_integer_number(*values):
 	if not all(map(is_integer_number, values)):
 		raise errors.EvaluationError('data type mismatch (not an integer number)')
@@ -401,7 +405,7 @@ def to_graphviz(self, digraph, *args, **kwargs):
 
 class AddExpression(LeftOperatorRightExpressionBase):
 	"""A class for representing addition expressions from the grammar text."""
-	compatible_types = (DataType.FLOAT, DataType.STRING, DataType.DATETIME, DataType.TIMEDELTA)
+	compatible_types = (DataType.BYTES, DataType.FLOAT, DataType.STRING, DataType.DATETIME, DataType.TIMEDELTA)
 	result_type = DataType.UNDEFINED
 
 	def __init__(self, *args, **kwargs):
@@ -429,6 +433,8 @@ def _op_add(self, thing):
 		elif isinstance(left_value, datetime.timedelta):
 			if not isinstance(right_value, (datetime.timedelta, datetime.datetime)):
 				raise errors.EvaluationError('data type mismatch (not a datetime or timedelta value)')
+		elif isinstance(left_value, bytes) or isinstance(right_value, bytes):
+			_assert_is_bytes(left_value, right_value)
 		elif isinstance(left_value, str) or isinstance(right_value, str):
 			_assert_is_string(left_value, right_value)
 		else:
@@ -711,8 +717,8 @@ class ContainsExpression(ExpressionBase):
 	__slots__ = ('container', 'member')
 	result_type = DataType.BOOLEAN
 	def __init__(self, context, container, member):
-		if container.result_type == DataType.STRING:
-			if member.result_type != DataType.UNDEFINED and member.result_type != DataType.STRING:
+		if container.result_type == DataType.BYTES or container.result_type == DataType.STRING:
+			if member.result_type != DataType.UNDEFINED and member.result_type != container.result_type:
 				raise errors.EvaluationError('data type mismatch')
 		elif container.result_type != DataType.UNDEFINED and container.result_type.is_scalar:
 			raise errors.EvaluationError('data type mismatch')
@@ -835,7 +841,11 @@ def __init__(self, context, container, item, safe=False):
 		"""
 		self.context = context
 		self.container = container
-		if container.result_type == DataType.STRING:
+		if container.result_type == DataType.BYTES:
+			if not DataType.is_compatible(item.result_type, DataType.FLOAT):
+				raise errors.EvaluationError('data type mismatch (not an integer number)')
+			self.result_type = DataType.FLOAT
+		elif container.result_type == DataType.STRING:
 			if not DataType.is_compatible(item.result_type, DataType.FLOAT):
 				raise errors.EvaluationError('data type mismatch (not an integer number)')
 			self.result_type = DataType.STRING
@@ -872,7 +882,7 @@ def evaluate(self, thing):
 			raise errors.EvaluationError('data type mismatch (container is null)')
 
 		resolved_item = self.item.evaluate(thing)
-		if isinstance(resolved_obj, (str, tuple)):
+		if isinstance(resolved_obj, (bytes, str, tuple)):
 			_assert_is_integer_number(resolved_item)
 			resolved_item = int(resolved_item)
 		try:
@@ -915,7 +925,9 @@ def __init__(self, context, container, start=None, stop=None, safe=False):
 		"""
 		self.context = context
 		self.container = container
-		if container.result_type == DataType.STRING:
+		if container.result_type == DataType.BYTES:
+			self.result_type = DataType.BYTES
+		elif container.result_type == DataType.STRING:
 			self.result_type = DataType.STRING
 		# check against __class__ so the parent class is dynamic in case it changes in the future, what we're doing here
 		# is explicitly checking if result_type is an array with out checking the value_type