forked from vlasovskikh/funcparserlib
-
Notifications
You must be signed in to change notification settings - Fork 0
/
dot.py
205 lines (178 loc) · 6.26 KB
/
dot.py
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
# -*- coding: utf-8 -*-
r"""A DOT language parser using funcparserlib.
The parser is based on [the DOT grammar][1]. It is pretty complete with a few
not supported things:
* String ecapes `\"`
* Ports and compass points
* XML identifiers
At the moment, the parser builds only a parse tree, not an abstract syntax tree
(AST) or an API for dealing with DOT.
[1]: http://www.graphviz.org/doc/info/lang.html
"""
import sys
import os
from re import MULTILINE
from funcparserlib.util import pretty_tree
from funcparserlib.lexer import make_tokenizer, Token, LexerError
from funcparserlib.parser import (some, a, maybe, many, finished, skip,
oneplus, forward_decl, NoParseError)
try:
from collections import namedtuple
except ImportError:
# Basic implementation of namedtuple for 2.1 < Python < 2.6
def namedtuple(name, fields):
"""Only space-delimited fields are supported."""
def prop(i, name):
return name, property(lambda self: self[i])
def new(cls, *args, **kwargs):
args = list(args)
n = len(args)
for i in range(n, len(names)):
name = names[i - n]
args.append(kwargs[name])
return tuple.__new__(cls, args)
names = dict((i, f) for i, f in enumerate(fields.split(u' ')))
methods = dict(prop(i, f) for i, f in enumerate(fields.split(u' ')))
methods.update({
'__new__': new,
'__repr__': lambda self: u'%s(%s)' % (
name,
u', '.join(u'%s=%r' % (
f, getattr(self, f)) for f in fields.split(u' ')))})
return type(name, (tuple,), methods)
ENCODING = u'UTF-8'
Graph = namedtuple('Graph', 'strict type id stmts')
SubGraph = namedtuple('SubGraph', 'id stmts')
Node = namedtuple('Node', 'id attrs')
Attr = namedtuple('Attr', 'name value')
Edge = namedtuple('Edge', 'nodes attrs')
DefAttrs = namedtuple('DefAttrs', 'object attrs')
def tokenize(str):
"""str -> Sequence(Token)"""
specs = [
(u'Comment', (ur'/\*(.|[\r\n])*?\*/', MULTILINE)),
(u'Comment', (ur'//.*',)),
(u'NL', (ur'[\r\n]+',)),
(u'Space', (ur'[ \t\r\n]+',)),
(u'Name', (ur'[A-Za-z\200-\377_][A-Za-z\200-\377_0-9]*',)),
(u'Op', (ur'[{};,=\[\]]|(->)|(--)',)),
(u'Number', (ur'-?(\.[0-9]+)|([0-9]+(\.[0-9]*)?)',)),
(u'String', (ur'"[^"]*"',)), # '\"' escapes are ignored
]
useless = [u'Comment', u'NL', u'Space']
t = make_tokenizer(specs)
return [x for x in t(str) if x.type not in useless]
def parse(seq):
"""Sequence(Token) -> object"""
unarg = lambda f: lambda args: f(*args)
tokval = lambda x: x.value
flatten = lambda list: sum(list, [])
n = lambda s: a(Token(u'Name', s)) >> tokval
op = lambda s: a(Token(u'Op', s)) >> tokval
op_ = lambda s: skip(op(s))
id_types = [u'Name', u'Number', u'String']
id = some(lambda t: t.type in id_types).named(u'id') >> tokval
make_graph_attr = lambda args: DefAttrs(u'graph', [Attr(*args)])
make_edge = lambda x, xs, attrs: Edge([x] + xs, attrs)
node_id = id # + maybe(port)
a_list = (
id +
maybe(op_(u'=') + id) +
skip(maybe(op(u',')))
>> unarg(Attr))
attr_list = (
many(op_(u'[') + many(a_list) + op_(u']'))
>> flatten)
attr_stmt = (
(n(u'graph') | n(u'node') | n(u'edge')) +
attr_list
>> unarg(DefAttrs))
graph_attr = id + op_(u'=') + id >> make_graph_attr
node_stmt = node_id + attr_list >> unarg(Node)
# We use a forward_decl becaue of circular definitions like (stmt_list ->
# stmt -> subgraph -> stmt_list)
subgraph = forward_decl()
edge_rhs = skip(op(u'->') | op(u'--')) + (subgraph | node_id)
edge_stmt = (
(subgraph | node_id) +
oneplus(edge_rhs) +
attr_list
>> unarg(make_edge))
stmt = (
attr_stmt
| edge_stmt
| subgraph
| graph_attr
| node_stmt
)
stmt_list = many(stmt + skip(maybe(op(u';'))))
subgraph.define(
skip(n(u'subgraph')) +
maybe(id) +
op_(u'{') +
stmt_list +
op_(u'}')
>> unarg(SubGraph))
graph = (
maybe(n(u'strict')) +
maybe(n(u'graph') | n(u'digraph')) +
maybe(id) +
op_(u'{') +
stmt_list +
op_(u'}')
>> unarg(Graph))
dotfile = graph + skip(finished)
return dotfile.parse(seq)
def pretty_parse_tree(x):
"""object -> str"""
Pair = namedtuple(u'Pair', u'first second')
p = lambda x, y: Pair(x, y)
def kids(x):
"""object -> list(object)"""
if isinstance(x, (Graph, SubGraph)):
return [p(u'stmts', x.stmts)]
elif isinstance(x, (Node, DefAttrs)):
return [p(u'attrs', x.attrs)]
elif isinstance(x, Edge):
return [p(u'nodes', x.nodes), p(u'attrs', x.attrs)]
elif isinstance(x, Pair):
return x.second
else:
return []
def show(x):
"""object -> str"""
if isinstance(x, Pair):
return x.first
elif isinstance(x, Graph):
return u'Graph [id=%s, strict=%r, type=%s]' % (
x.id, x.strict is not None, x.type)
elif isinstance(x, SubGraph):
return u'SubGraph [id=%s]' % (x.id,)
elif isinstance(x, Edge):
return u'Edge'
elif isinstance(x, Attr):
return u'Attr [name=%s, value=%s]' % (x.name, x.value)
elif isinstance(x, DefAttrs):
return u'DefAttrs [object=%s]' % (x.object,)
elif isinstance(x, Node):
return u'Node [id=%s]' % (x.id,)
else:
return unicode(x)
return pretty_tree(x, kids, show)
def main():
#import logging
#logging.basicConfig(level=logging.DEBUG)
#import funcparserlib
#funcparserlib.parser.debug = True
try:
stdin = os.fdopen(sys.stdin.fileno(), u'rb')
input = stdin.read().decode(ENCODING)
tree = parse(tokenize(input))
#print pformat(tree)
print pretty_parse_tree(tree).encode(ENCODING)
except (NoParseError, LexerError), e:
msg = (u'syntax error: %s' % e).encode(ENCODING)
print >> sys.stderr, msg
sys.exit(1)
if __name__ == '__main__':
main()