322 lines
11 KiB
Python
322 lines
11 KiB
Python
"""
|
|
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
|
|
|
|
|
|
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)
|
|
try:
|
|
if not result:
|
|
break
|
|
except KeyboardInterrupt:
|
|
raise
|
|
except:
|
|
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)
|
|
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
|