/usr/lib/python3/dist-packages/mccabe.py is in python3-mccabe 0.2.1-1.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 | """ Meager code path measurement tool.
Ned Batchelder
http://nedbatchelder.com/blog/200803/python_code_complexity_microtool.html
MIT License.
"""
from __future__ import with_statement
import optparse
import sys
from collections import defaultdict
try:
import ast
from ast import iter_child_nodes
except ImportError: # Python 2.5
from flake8.util import ast, iter_child_nodes
__version__ = '0.2.1'
class ASTVisitor(object):
"""Performs a depth-first walk of the AST."""
def __init__(self):
self.node = None
self._cache = {}
def default(self, node, *args):
for child in iter_child_nodes(node):
self.dispatch(child, *args)
def dispatch(self, node, *args):
self.node = node
klass = node.__class__
meth = self._cache.get(klass)
if meth is None:
className = klass.__name__
meth = getattr(self.visitor, 'visit' + className, self.default)
self._cache[klass] = meth
return meth(node, *args)
def preorder(self, tree, visitor, *args):
"""Do preorder walk of tree using visitor"""
self.visitor = visitor
visitor.visit = self.dispatch
self.dispatch(tree, *args) # XXX *args make sense?
class PathNode(object):
def __init__(self, name, look="circle"):
self.name = name
self.look = look
def to_dot(self):
print('node [shape=%s,label="%s"] %d;' % (
self.look, self.name, self.dot_id()))
def dot_id(self):
return id(self)
class PathGraph(object):
def __init__(self, name, entity, lineno):
self.name = name
self.entity = entity
self.lineno = lineno
self.nodes = defaultdict(list)
def connect(self, n1, n2):
self.nodes[n1].append(n2)
def to_dot(self):
print('subgraph {')
for node in self.nodes:
node.to_dot()
for node, nexts in self.nodes.items():
for next in nexts:
print('%s -- %s;' % (node.dot_id(), next.dot_id()))
print('}')
def complexity(self):
""" Return the McCabe complexity for the graph.
V-E+2
"""
num_edges = sum([len(n) for n in self.nodes.values()])
num_nodes = len(self.nodes)
return num_edges - num_nodes + 2
class PathGraphingAstVisitor(ASTVisitor):
""" A visitor for a parsed Abstract Syntax Tree which finds executable
statements.
"""
def __init__(self):
super(PathGraphingAstVisitor, self).__init__()
self.classname = ""
self.graphs = {}
self.reset()
def reset(self):
self.graph = None
self.tail = None
def dispatch_list(self, node_list):
for node in node_list:
self.dispatch(node)
def visitFunctionDef(self, node):
if self.classname:
entity = '%s%s' % (self.classname, node.name)
else:
entity = node.name
name = '%d:1: %r' % (node.lineno, entity)
if self.graph is not None:
# closure
pathnode = self.appendPathNode(name)
self.tail = pathnode
self.dispatch_list(node.body)
bottom = PathNode("", look='point')
self.graph.connect(self.tail, bottom)
self.graph.connect(pathnode, bottom)
self.tail = bottom
else:
self.graph = PathGraph(name, entity, node.lineno)
pathnode = PathNode(name)
self.tail = pathnode
self.dispatch_list(node.body)
self.graphs["%s%s" % (self.classname, node.name)] = self.graph
self.reset()
def visitClassDef(self, node):
old_classname = self.classname
self.classname += node.name + "."
self.dispatch_list(node.body)
self.classname = old_classname
def appendPathNode(self, name):
if not self.tail:
return
pathnode = PathNode(name)
self.graph.connect(self.tail, pathnode)
self.tail = pathnode
return pathnode
def visitSimpleStatement(self, node):
if node.lineno is None:
lineno = 0
else:
lineno = node.lineno
name = "Stmt %d" % lineno
self.appendPathNode(name)
visitAssert = visitAssign = visitAugAssign = visitDelete = visitPrint = \
visitRaise = visitYield = visitImport = visitCall = visitSubscript = \
visitPass = visitContinue = visitBreak = visitGlobal = visitReturn = \
visitSimpleStatement
def visitLoop(self, node):
name = "Loop %d" % node.lineno
if self.graph is None:
# global loop
self.graph = PathGraph(name, name, node.lineno)
pathnode = PathNode(name)
self.tail = pathnode
self.dispatch_list(node.body)
self.graphs["%s%s" % (self.classname, name)] = self.graph
self.reset()
else:
pathnode = self.appendPathNode(name)
self.tail = pathnode
self.dispatch_list(node.body)
bottom = PathNode("", look='point')
self.graph.connect(self.tail, bottom)
self.graph.connect(pathnode, bottom)
self.tail = bottom
# TODO: else clause in node.orelse
visitFor = visitWhile = visitLoop
def visitIf(self, node):
name = "If %d" % node.lineno
pathnode = self.appendPathNode(name)
loose_ends = []
self.dispatch_list(node.body)
loose_ends.append(self.tail)
if node.orelse:
self.tail = pathnode
self.dispatch_list(node.orelse)
loose_ends.append(self.tail)
else:
loose_ends.append(pathnode)
if pathnode:
bottom = PathNode("", look='point')
for le in loose_ends:
self.graph.connect(le, bottom)
self.tail = bottom
def visitTryExcept(self, node):
name = "TryExcept %d" % node.lineno
pathnode = self.appendPathNode(name)
loose_ends = []
self.dispatch_list(node.body)
loose_ends.append(self.tail)
for handler in node.handlers:
self.tail = pathnode
self.dispatch_list(handler.body)
loose_ends.append(self.tail)
if pathnode:
bottom = PathNode("", look='point')
for le in loose_ends:
self.graph.connect(le, bottom)
self.tail = bottom
def visitWith(self, node):
name = "With %d" % node.lineno
self.appendPathNode(name)
self.dispatch_list(node.body)
class McCabeChecker(object):
"""McCabe cyclomatic complexity checker."""
name = 'mccabe'
version = __version__
_code = 'C901'
_error_tmpl = "C901 %r is too complex (%d)"
max_complexity = 0
def __init__(self, tree, filename):
self.tree = tree
@classmethod
def add_options(cls, parser):
parser.add_option('--max-complexity', default=-1, action='store',
type='int', help="McCabe complexity threshold")
parser.config_options.append('max-complexity')
@classmethod
def parse_options(cls, options):
cls.max_complexity = options.max_complexity
def run(self):
if self.max_complexity < 0:
return
visitor = PathGraphingAstVisitor()
visitor.preorder(self.tree, visitor)
for graph in visitor.graphs.values():
if graph.complexity() >= self.max_complexity:
text = self._error_tmpl % (graph.entity, graph.complexity())
yield graph.lineno, 0, text, type(self)
def get_code_complexity(code, threshold=7, filename='stdin'):
try:
tree = compile(code, filename, "exec", ast.PyCF_ONLY_AST)
except SyntaxError:
e = sys.exc_info()[1]
sys.stderr.write("Unable to parse %s: %s\n" % (filename, e))
return 0
complx = []
McCabeChecker.max_complexity = threshold
for lineno, offset, text, check in McCabeChecker(tree, filename).run():
complx.append('%s:%d:1: %s' % (filename, lineno, text))
if len(complx) == 0:
return 0
print('\n'.join(complx))
return len(complx)
def get_module_complexity(module_path, threshold=7):
"""Returns the complexity of a module"""
with open(module_path, "rU") as mod:
code = mod.read()
return get_code_complexity(code, threshold, filename=module_path)
def main(argv):
opar = optparse.OptionParser()
opar.add_option("-d", "--dot", dest="dot",
help="output a graphviz dot file", action="store_true")
opar.add_option("-m", "--min", dest="threshold",
help="minimum complexity for output", type="int",
default=2)
options, args = opar.parse_args(argv)
with open(args[0], "rU") as mod:
code = mod.read()
tree = compile(code, args[0], "exec", ast.PyCF_ONLY_AST)
visitor = PathGraphingAstVisitor()
visitor.preorder(tree, visitor)
if options.dot:
print('graph {')
for graph in visitor.graphs.values():
if graph.complexity() >= options.threshold:
graph.to_dot()
print('}')
else:
for graph in visitor.graphs.values():
if graph.complexity() >= options.threshold:
print(graph.name, graph.complexity())
if __name__ == '__main__':
main(sys.argv[1:])
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