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"""Simple traceback introspection. Used to add additional information to
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AssertionErrors in tests, so that failure messages may be more informative.
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from cStringIO import StringIO
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from StringIO import StringIO
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log = logging.getLogger(__name__)
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def inspect_traceback(tb):
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"""Inspect a traceback and its frame, returning source for the expression
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where the exception was raised, with simple variable replacement performed
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and the line on which the exception was raised marked with '>>'
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log.debug('inspect traceback %s', tb)
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# we only want the innermost frame, where the exception was raised
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lines, exc_line = tbsource(tb)
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# figure out the set of lines to grab.
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inspect_lines, mark_line = find_inspectable_lines(lines, exc_line)
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src = StringIO(textwrap.dedent(''.join(inspect_lines)))
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exp = Expander(frame.f_locals, frame.f_globals)
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tokenize.tokenize(src.readline, exp)
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except tokenize.TokenError, e:
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# this can happen if our inspectable region happens to butt up
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# against the end of a construct like a docstring with the closing
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# """ on separate line
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log.debug("Tokenizer error: %s", e)
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src = StringIO(textwrap.dedent(''.join(inspect_lines)))
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exp = Expander(frame.f_locals, frame.f_globals)
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if exp.expanded_source:
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exp_lines = exp.expanded_source.split('\n')
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for line in exp_lines:
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padded.append('>> ' + line)
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padded.append(' ' + line)
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return '\n'.join(padded)
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def tbsource(tb, context=6):
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"""Get source from a traceback object.
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A tuple of two things is returned: a list of lines of context from
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the source code, and the index of the current line within that list.
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The optional second argument specifies the number of lines of context
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to return, which are centered around the current line.
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This is adapted from inspect.py in the python 2.4 standard library,
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since a bug in the 2.3 version of inspect prevents it from correctly
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locating source lines in a traceback frame.
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start = lineno - 1 - context//2
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log.debug("lineno: %s start: %s", lineno, start)
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lines, dummy = inspect.findsource(frame)
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lines, index = [''], 0
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start = max(0, min(start, len(lines) - context))
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lines = lines[start:start+context]
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index = lineno - 1 - start
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# python 2.5 compat: if previous line ends in a continuation,
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# decrement start by 1 to match 2.4 behavior
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if sys.version_info >= (2, 5) and index > 0:
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while lines[index-1].strip().endswith('\\'):
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lines = all_lines[start:start+context]
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lines, index = [''], 0
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log.debug("tbsource lines '''%s''' around index %s", lines, index)
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return (lines, index)
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def find_inspectable_lines(lines, pos):
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"""Find lines in home that are inspectable.
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Walk back from the err line up to 3 lines, but don't walk back over
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changes in indent level.
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Walk forward up to 3 lines, counting \ separated lines as 1. Don't walk
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over changes in indent level (unless part of an extended line)
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cnt = re.compile(r'\\[\s\n]*$')
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df = re.compile(r':[\s\n]*$')
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ind = re.compile(r'^(\s*)')
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home_indent = ind.match(home).groups()[0]
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before = lines[max(pos-3, 0):pos]
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after = lines[pos+1:min(pos+4, len(lines))]
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if ind.match(line).groups()[0] == home_indent:
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toinspect.append(line)
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toinspect.append(home)
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home_pos = len(toinspect)-1
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continued = cnt.search(home)
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if ((continued or ind.match(line).groups()[0] == home_indent)
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and not df.search(line)):
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toinspect.append(line)
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continued = cnt.search(line)
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log.debug("Inspecting lines '''%s''' around %s", toinspect, home_pos)
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return toinspect, home_pos
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"""Simple expression expander. Uses tokenize to find the names and
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expands any that can be looked up in the frame.
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def __init__(self, locals, globals):
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self.globals = globals
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self.expanded_source = ''
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def __call__(self, ttype, tok, start, end, line):
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# deal with unicode properly
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# Dealing with instance members
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# always keep the last thing seen
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# if the current token is a dot,
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# get ready to getattr(lastthing, this thing) on the
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if self.lpos is not None and start[1] >= self.lpos:
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self.expanded_source += ' ' * (start[1]-self.lpos)
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elif start[1] < self.lpos:
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# newline, indent correctly
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self.expanded_source += ' ' * start[1]
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if ttype == tokenize.INDENT:
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elif ttype == tokenize.NAME:
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val = self.locals[tok]
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val = self.globals[tok]
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# FIXME... not sure how to handle things like funcs, classes
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# FIXME this is broken for some unicode strings
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self.expanded_source += val
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self.expanded_source += tok
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# if this is the end of the line and the line ends with
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# \, then tack a \ and newline onto the output
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# print line[end[1]:]
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if re.match(r'\s+\\\n', line[end[1]:]):
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self.expanded_source += ' \\\n'
added
removed
third_party/nose-0.11.3/lib/python/nose/inspector.py
