Source code for jasy.style.process.Operation

#
# Jasy - Web Tooling Framework
# Copyright 2013-2014 Sebastian Werner
#

import jasy.style.Util as Util
import jasy.style.parse.Node as Node


[docs]class OperationError(Exception): def __init__(self, message, node): Exception.__init__(self, "Variable Error: %s for node type=%s in %s at line %s!" % (message, node.type, node.getFileName(), node.line))
[docs]def castToBool(node): """Returns the boolean Python representation for the given Node.""" if node.type == "false" or node.type == "null": return False elif node.type == "true": return True elif node.type == "number": return node.value != 0 elif node.type == "string": return len(node.value) > 0 else: raise OperationError("Could not cast node to boolean value", node)
[docs]def compute(node, first=None, second=None, operator=None, session=None): """ Recursively processes given operation node. Consumes optional hints for the first/second child of an operation as well as the operator itself (in cases where it could not be figured out automatically). The session is useful for supporting commands inside of operations. """ # Fill gaps in empty arguments if operator is None: operator = node.type # Fill missing first/second param if first is None and len(node) >= 1: first = node[0] if second is None and len(node) >= 2: second = node[1] # Error handling if node is None or operator is None: raise OperationError("Missing arguments for operation compute()", node) # Solve inner operations first if first is not None: if first.type in Util.ALL_OPERATORS: first = compute(first, session=session) elif first.type == "command": first = Util.executeCommand(first, session) if second is not None: if second.type in Util.ALL_OPERATORS: second = compute(second, session=session) elif second.type == "command": second = Util.executeCommand(second, session) # Support for not-/and-/or-operator if operator == "not": return Util.castNativeToNode(not castToBool(first)) elif operator == "and": return Util.castNativeToNode(castToBool(first) and castToBool(second)) elif operator == "or": return Util.castNativeToNode(castToBool(first) or castToBool(second)) # Support for default set operator "?=" when variable was not defined before elif operator == "questionmark" and first is None: return second # Ignore when not yet processed if first.type in ("command", "variable") or second.type in ("command", "variable"): return # Compare operation types elif first.type == second.type: if first.type in ("true", "false", "null"): if operator in ("eq", "ge", "le"): return Util.castNativeToNode(True) else: return Util.castNativeToNode(False) elif first.type == "number": firstUnit = getattr(first, "unit", None) secondUnit = getattr(second, "unit", None) if operator in Util.COMPARE_OPERATORS: if firstUnit == secondUnit or firstUnit is None or secondUnit is None: if operator == "eq": return Util.castNativeToNode(first.value == second.value) elif operator == "ne": return Util.castNativeToNode(first.value != second.value) elif operator == "gt": return Util.castNativeToNode(first.value > second.value) elif operator == "lt": return Util.castNativeToNode(first.value < second.value) elif operator == "ge": return Util.castNativeToNode(first.value >= second.value) elif operator == "le": return Util.castNativeToNode(first.value <= second.value) else: raise OperationError("Unsupported unit combination for number comparison", node) elif firstUnit == secondUnit or firstUnit is None or secondUnit is None: if operator in Util.MATH_OPERATORS: repl = Node.Node(type="number") if firstUnit is not None: repl.unit = firstUnit elif secondUnit is not None: repl.unit = secondUnit if operator == "plus": repl.value = first.value + second.value elif operator == "minus": repl.value = first.value - second.value elif operator == "mul": repl.value = first.value * second.value elif operator == "div": repl.value = first.value / second.value elif operator == "mod": repl.value = first.value % second.value return repl elif operator == "questionmark": return first else: raise OperationError("Unsupported number operation", node) elif firstUnit == "%" or secondUnit == "%": if operator in ("mul", "div"): repl = Node.Node(type="number") if operator == "mul": repl.value = first.value * second.value / 100 elif operator == "mul": repl.value = first.value / second.value / 100 if firstUnit == "%": repl.unit = secondUnit else: repl.unit = firstUnit return repl else: raise OperationError("Could not compute mixed percent operations for operators other than \"*\" and \"/\"", node) else: raise OperationError("Could not compute result from numbers of different units: %s vs %s" % (first.unit, second.unit), node) elif first.type == "string": if operator == "plus": repl = Node.Node(type="string") repl.value = first.value + second.value return repl elif operator == "eq": return Util.castNativeToNode(first.value == second.value) elif operator == "ne": return Util.castNativeToNode(first.value != second.value) else: raise OperationError("Unsupported string operation", node) elif first.type == "list": if len(first) == len(second): repl = Node.Node(type="list") for pos, child in enumerate(first): childRepl = compute(node, first=child, second=second[pos], session=session) if childRepl is not None: repl.append(childRepl) return repl else: raise OperationError("For list operations both lists have to have the same length!", node) else: raise OperationError("Unsupported operation on %s" % first.type, node) elif first.type == "true" and second.type == "false": return Util.castNativeToNode(False) elif first.type == "false" and second.type == "true": return Util.castNativeToNode(False) elif first.type == "list" and second.type != "list": repl = Node.Node(type="list") for child in first: childRepl = compute(node, first=child, second=second, session=session) if childRepl is not None: repl.append(childRepl) return repl elif first.type != "list" and second.type == "list": repl = Node.Node(type="list") for child in second: childRepl = compute(node, first=first, second=child, session=session) if childRepl is not None: repl.append(childRepl) return repl elif first.type == "string" or second.type == "string": repl = Node.Node(type="string") if first.type == "identifier" or second.type == "identifier": if operator == "plus": repl.value = first.value + second.value return repl elif operator == "eq": return Util.castNativeToNode(first.value == second.value) elif operator == "ne": return Util.castNativeToNode(first.value != second.value) else: raise OperationError("Unsupported string/identifier operation", node) else: if operator == "plus": repl.value = str(first.value) + str(second.value) return repl else: raise OperationError("Unsupported string operation", node) # Just handle when not both are null - equal condition is already done before elif first.type == "null" or second.type == "null": if operator == "eq": return Util.castNativeToNode(False) elif operator == "ne": return Util.castNativeToNode(True) elif operator in Util.MATH_OPERATORS: return Util.castNativeToNode(None) else: raise OperationError("Unsupported operation on null type", node) else: raise OperationError("Different types in operation: %s vs %s" % (first.type, second.type), node)