--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/eggs/py-1.4.0-py2.6.egg/py/_code/_assertionnew.py Sat Jan 08 11:20:57 2011 +0530
@@ -0,0 +1,345 @@
+"""
+Find intermediate evalutation results in assert statements through builtin AST.
+This should replace _assertionold.py eventually.
+"""
+
+import sys
+import ast
+
+import py
+from py._code.assertion import _format_explanation, BuiltinAssertionError
+
+
+if sys.platform.startswith("java") and sys.version_info < (2, 5, 2):
+ # See http://bugs.jython.org/issue1497
+ _exprs = ("BoolOp", "BinOp", "UnaryOp", "Lambda", "IfExp", "Dict",
+ "ListComp", "GeneratorExp", "Yield", "Compare", "Call",
+ "Repr", "Num", "Str", "Attribute", "Subscript", "Name",
+ "List", "Tuple")
+ _stmts = ("FunctionDef", "ClassDef", "Return", "Delete", "Assign",
+ "AugAssign", "Print", "For", "While", "If", "With", "Raise",
+ "TryExcept", "TryFinally", "Assert", "Import", "ImportFrom",
+ "Exec", "Global", "Expr", "Pass", "Break", "Continue")
+ _expr_nodes = set(getattr(ast, name) for name in _exprs)
+ _stmt_nodes = set(getattr(ast, name) for name in _stmts)
+ def _is_ast_expr(node):
+ return node.__class__ in _expr_nodes
+ def _is_ast_stmt(node):
+ return node.__class__ in _stmt_nodes
+else:
+ def _is_ast_expr(node):
+ return isinstance(node, ast.expr)
+ def _is_ast_stmt(node):
+ return isinstance(node, ast.stmt)
+
+
+class Failure(Exception):
+ """Error found while interpreting AST."""
+
+ def __init__(self, explanation=""):
+ self.cause = sys.exc_info()
+ self.explanation = explanation
+
+
+def interpret(source, frame, should_fail=False):
+ mod = ast.parse(source)
+ visitor = DebugInterpreter(frame)
+ try:
+ visitor.visit(mod)
+ except Failure:
+ failure = sys.exc_info()[1]
+ return getfailure(failure)
+ if should_fail:
+ return ("(assertion failed, but when it was re-run for "
+ "printing intermediate values, it did not fail. Suggestions: "
+ "compute assert expression before the assert or use --no-assert)")
+
+def run(offending_line, frame=None):
+ if frame is None:
+ frame = py.code.Frame(sys._getframe(1))
+ return interpret(offending_line, frame)
+
+def getfailure(failure):
+ explanation = _format_explanation(failure.explanation)
+ value = failure.cause[1]
+ if str(value):
+ lines = explanation.splitlines()
+ if not lines:
+ lines.append("")
+ lines[0] += " << %s" % (value,)
+ explanation = "\n".join(lines)
+ text = "%s: %s" % (failure.cause[0].__name__, explanation)
+ if text.startswith("AssertionError: assert "):
+ text = text[16:]
+ return text
+
+
+operator_map = {
+ ast.BitOr : "|",
+ ast.BitXor : "^",
+ ast.BitAnd : "&",
+ ast.LShift : "<<",
+ ast.RShift : ">>",
+ ast.Add : "+",
+ ast.Sub : "-",
+ ast.Mult : "*",
+ ast.Div : "/",
+ ast.FloorDiv : "//",
+ ast.Mod : "%",
+ ast.Eq : "==",
+ ast.NotEq : "!=",
+ ast.Lt : "<",
+ ast.LtE : "<=",
+ ast.Gt : ">",
+ ast.GtE : ">=",
+ ast.Pow : "**",
+ ast.Is : "is",
+ ast.IsNot : "is not",
+ ast.In : "in",
+ ast.NotIn : "not in"
+}
+
+unary_map = {
+ ast.Not : "not %s",
+ ast.Invert : "~%s",
+ ast.USub : "-%s",
+ ast.UAdd : "+%s"
+}
+
+
+class DebugInterpreter(ast.NodeVisitor):
+ """Interpret AST nodes to gleam useful debugging information. """
+
+ def __init__(self, frame):
+ self.frame = frame
+
+ def generic_visit(self, node):
+ # Fallback when we don't have a special implementation.
+ if _is_ast_expr(node):
+ mod = ast.Expression(node)
+ co = self._compile(mod)
+ try:
+ result = self.frame.eval(co)
+ except Exception:
+ raise Failure()
+ explanation = self.frame.repr(result)
+ return explanation, result
+ elif _is_ast_stmt(node):
+ mod = ast.Module([node])
+ co = self._compile(mod, "exec")
+ try:
+ self.frame.exec_(co)
+ except Exception:
+ raise Failure()
+ return None, None
+ else:
+ raise AssertionError("can't handle %s" %(node,))
+
+ def _compile(self, source, mode="eval"):
+ return compile(source, "<assertion interpretation>", mode)
+
+ def visit_Expr(self, expr):
+ return self.visit(expr.value)
+
+ def visit_Module(self, mod):
+ for stmt in mod.body:
+ self.visit(stmt)
+
+ def visit_Name(self, name):
+ explanation, result = self.generic_visit(name)
+ # See if the name is local.
+ source = "%r in locals() is not globals()" % (name.id,)
+ co = self._compile(source)
+ try:
+ local = self.frame.eval(co)
+ except Exception:
+ # have to assume it isn't
+ local = False
+ if not local:
+ return name.id, result
+ return explanation, result
+
+ def visit_Compare(self, comp):
+ left = comp.left
+ left_explanation, left_result = self.visit(left)
+ for op, next_op in zip(comp.ops, comp.comparators):
+ next_explanation, next_result = self.visit(next_op)
+ op_symbol = operator_map[op.__class__]
+ explanation = "%s %s %s" % (left_explanation, op_symbol,
+ next_explanation)
+ source = "__exprinfo_left %s __exprinfo_right" % (op_symbol,)
+ co = self._compile(source)
+ try:
+ result = self.frame.eval(co, __exprinfo_left=left_result,
+ __exprinfo_right=next_result)
+ except Exception:
+ raise Failure(explanation)
+ if not result:
+ break
+ left_explanation, left_result = next_explanation, next_result
+
+ rcomp = py.code._reprcompare
+ if rcomp:
+ res = rcomp(op_symbol, left_result, next_result)
+ if res:
+ explanation = res
+ return explanation, result
+
+ def visit_BoolOp(self, boolop):
+ is_or = isinstance(boolop.op, ast.Or)
+ explanations = []
+ for operand in boolop.values:
+ explanation, result = self.visit(operand)
+ explanations.append(explanation)
+ if result == is_or:
+ break
+ name = is_or and " or " or " and "
+ explanation = "(" + name.join(explanations) + ")"
+ return explanation, result
+
+ def visit_UnaryOp(self, unary):
+ pattern = unary_map[unary.op.__class__]
+ operand_explanation, operand_result = self.visit(unary.operand)
+ explanation = pattern % (operand_explanation,)
+ co = self._compile(pattern % ("__exprinfo_expr",))
+ try:
+ result = self.frame.eval(co, __exprinfo_expr=operand_result)
+ except Exception:
+ raise Failure(explanation)
+ return explanation, result
+
+ def visit_BinOp(self, binop):
+ left_explanation, left_result = self.visit(binop.left)
+ right_explanation, right_result = self.visit(binop.right)
+ symbol = operator_map[binop.op.__class__]
+ explanation = "(%s %s %s)" % (left_explanation, symbol,
+ right_explanation)
+ source = "__exprinfo_left %s __exprinfo_right" % (symbol,)
+ co = self._compile(source)
+ try:
+ result = self.frame.eval(co, __exprinfo_left=left_result,
+ __exprinfo_right=right_result)
+ except Exception:
+ raise Failure(explanation)
+ return explanation, result
+
+ def visit_Call(self, call):
+ func_explanation, func = self.visit(call.func)
+ arg_explanations = []
+ ns = {"__exprinfo_func" : func}
+ arguments = []
+ for arg in call.args:
+ arg_explanation, arg_result = self.visit(arg)
+ arg_name = "__exprinfo_%s" % (len(ns),)
+ ns[arg_name] = arg_result
+ arguments.append(arg_name)
+ arg_explanations.append(arg_explanation)
+ for keyword in call.keywords:
+ arg_explanation, arg_result = self.visit(keyword.value)
+ arg_name = "__exprinfo_%s" % (len(ns),)
+ ns[arg_name] = arg_result
+ keyword_source = "%s=%%s" % (keyword.arg)
+ arguments.append(keyword_source % (arg_name,))
+ arg_explanations.append(keyword_source % (arg_explanation,))
+ if call.starargs:
+ arg_explanation, arg_result = self.visit(call.starargs)
+ arg_name = "__exprinfo_star"
+ ns[arg_name] = arg_result
+ arguments.append("*%s" % (arg_name,))
+ arg_explanations.append("*%s" % (arg_explanation,))
+ if call.kwargs:
+ arg_explanation, arg_result = self.visit(call.kwargs)
+ arg_name = "__exprinfo_kwds"
+ ns[arg_name] = arg_result
+ arguments.append("**%s" % (arg_name,))
+ arg_explanations.append("**%s" % (arg_explanation,))
+ args_explained = ", ".join(arg_explanations)
+ explanation = "%s(%s)" % (func_explanation, args_explained)
+ args = ", ".join(arguments)
+ source = "__exprinfo_func(%s)" % (args,)
+ co = self._compile(source)
+ try:
+ result = self.frame.eval(co, **ns)
+ except Exception:
+ raise Failure(explanation)
+ # Only show result explanation if it's not a builtin call or returns a
+ # bool.
+ if not isinstance(call.func, ast.Name) or \
+ not self._is_builtin_name(call.func):
+ source = "isinstance(__exprinfo_value, bool)"
+ co = self._compile(source)
+ try:
+ is_bool = self.frame.eval(co, __exprinfo_value=result)
+ except Exception:
+ is_bool = False
+ if not is_bool:
+ pattern = "%s\n{%s = %s\n}"
+ rep = self.frame.repr(result)
+ explanation = pattern % (rep, rep, explanation)
+ return explanation, result
+
+ def _is_builtin_name(self, name):
+ pattern = "%r not in globals() and %r not in locals()"
+ source = pattern % (name.id, name.id)
+ co = self._compile(source)
+ try:
+ return self.frame.eval(co)
+ except Exception:
+ return False
+
+ def visit_Attribute(self, attr):
+ if not isinstance(attr.ctx, ast.Load):
+ return self.generic_visit(attr)
+ source_explanation, source_result = self.visit(attr.value)
+ explanation = "%s.%s" % (source_explanation, attr.attr)
+ source = "__exprinfo_expr.%s" % (attr.attr,)
+ co = self._compile(source)
+ try:
+ result = self.frame.eval(co, __exprinfo_expr=source_result)
+ except Exception:
+ raise Failure(explanation)
+ explanation = "%s\n{%s = %s.%s\n}" % (self.frame.repr(result),
+ self.frame.repr(result),
+ source_explanation, attr.attr)
+ # Check if the attr is from an instance.
+ source = "%r in getattr(__exprinfo_expr, '__dict__', {})"
+ source = source % (attr.attr,)
+ co = self._compile(source)
+ try:
+ from_instance = self.frame.eval(co, __exprinfo_expr=source_result)
+ except Exception:
+ from_instance = True
+ if from_instance:
+ rep = self.frame.repr(result)
+ pattern = "%s\n{%s = %s\n}"
+ explanation = pattern % (rep, rep, explanation)
+ return explanation, result
+
+ def visit_Assert(self, assrt):
+ test_explanation, test_result = self.visit(assrt.test)
+ if test_explanation.startswith("False\n{False =") and \
+ test_explanation.endswith("\n"):
+ test_explanation = test_explanation[15:-2]
+ explanation = "assert %s" % (test_explanation,)
+ if not test_result:
+ try:
+ raise BuiltinAssertionError
+ except Exception:
+ raise Failure(explanation)
+ return explanation, test_result
+
+ def visit_Assign(self, assign):
+ value_explanation, value_result = self.visit(assign.value)
+ explanation = "... = %s" % (value_explanation,)
+ name = ast.Name("__exprinfo_expr", ast.Load(),
+ lineno=assign.value.lineno,
+ col_offset=assign.value.col_offset)
+ new_assign = ast.Assign(assign.targets, name, lineno=assign.lineno,
+ col_offset=assign.col_offset)
+ mod = ast.Module([new_assign])
+ co = self._compile(mod, "exec")
+ try:
+ self.frame.exec_(co, __exprinfo_expr=value_result)
+ except Exception:
+ raise Failure(explanation)
+ return explanation, value_result