#<MROgraph.py>
"""
Draw inheritance hierarchies via Dot (http://www.graphviz.org/)
Author: Michele Simionato
E-mail: mis6@pitt.edu
Date: August 2003
License: Python-like
Requires: Python 2.3, dot, standard Unix tools
"""
import os,itertools
PSVIEWER='gv' # you may change these with
PNGVIEWER='kview' # your preferred viewers
PSFONT='Times' # you may change these too
PNGFONT='Courier' # on my system PNGFONT=Times does not work
def if_(cond,e1,e2=''):
"Ternary operator would be"
if cond: return e1
else: return e2
def MRO(cls):
"Returns the MRO of cls as a text"
out=["MRO of %s:" % cls.__name__]
for counter,c in enumerate(cls.__mro__):
name=c.__name__
bases=','.join([b.__name__ for b in c.__bases__])
s=" %s - %s(%s)" % (counter,name,bases)
if type(c) is not type: s+="[%s]" % type(c).__name__
out.append(s)
return '\n'.join(out)
class MROgraph(object):
def __init__(self,*classes,**options):
"Generates the MRO graph of a set of given classes."
if not classes: raise "Missing class argument!"
filename=options.get('filename',"MRO_of_%s.ps" % classes[0].__name__)
self.labels=options.get('labels',2)
caption=options.get('caption',False)
setup=options.get('setup','')
name,dotformat=os.path.splitext(filename)
format=dotformat[1:]
fontopt="fontname="+if_(format=='ps',PSFONT,PNGFONT)
nodeopt=' node [%s];\n' % fontopt
edgeopt=' edge [%s];\n' % fontopt
viewer=if_(format=='ps',PSVIEWER,PNGVIEWER)
self.textrepr='\n'.join([MRO(cls) for cls in classes])
caption=if_(caption,
'caption [shape=box,label="%s\n",fontsize=9];'
% self.textrepr).replace('\n','\\l')
setupcode=nodeopt+edgeopt+caption+'\n'+setup+'\n'
codeiter=itertools.chain(*[self.genMROcode(cls) for cls in classes])
self.dotcode='digraph %s{\n%s%s}' % (
name,setupcode,'\n'.join(codeiter))
os.system("echo '%s' | dot -T%s > %s; %s %s&" %
(self.dotcode,format,filename,viewer,filename))
def genMROcode(self,cls):
"Generates the dot code for the MRO of a given class"
for mroindex,c in enumerate(cls.__mro__):
name=c.__name__
manyparents=len(c.__bases__) > 1
if c.__bases__:
yield ''.join([
' edge [style=solid]; %s -> %s %s;\n' % (
b.__name__,name,if_(manyparents and self.labels==2,
'[label="%s"]' % (i+1)))
for i,b in enumerate(c.__bases__)])
if manyparents:
yield " {rank=same; %s}\n" % ''.join([
'"%s"; ' % b.__name__ for b in c.__bases__])
number=if_(self.labels,"%s-" % mroindex)
label='label="%s"' % (number+name)
option=if_(issubclass(cls,type), # if cls is a metaclass
'[%s]' % label,
'[shape=box,%s]' % label)
yield(' %s %s;\n' % (name,option))
if type(c) is not type: # c has a custom metaclass
metaname=type(c).__name__
yield ' edge [style=dashed]; %s -> %s;' % (metaname,name)
def __repr__(self):
"Returns the Dot representation of the graph"
return self.dotcode
def __str__(self):
"Returns a text representation of the MRO"
return self.textrepr
def testHierarchy(**options):
class M(type): pass # metaclass
class F(object): pass
class E(object): pass
class D(object): pass
class G(object): __metaclass__=M
class C(F,D,G): pass
class B(E,D): pass
class A(B,C): pass
return MROgraph(A,M,**options)
if __name__=="__main__":
testHierarchy() # generates a postscript diagram of A and M hierarchies
#</MROgraph.py>
