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
|
from __future__ import absolute_import
from __future__ import print_function
__all__ = ['Composer', 'ComposerError']
from .error import MarkedYAMLError
from .events import *
from .nodes import *
from .compat import utf8
class ComposerError(MarkedYAMLError):
pass
class Composer(object):
def __init__(self):
self.anchors = {}
def check_node(self):
# Drop the STREAM-START event.
if self.check_event(StreamStartEvent):
self.get_event()
# If there are more documents available?
return not self.check_event(StreamEndEvent)
def get_node(self):
# Get the root node of the next document.
if not self.check_event(StreamEndEvent):
return self.compose_document()
def get_single_node(self):
# Drop the STREAM-START event.
self.get_event()
# Compose a document if the stream is not empty.
document = None
if not self.check_event(StreamEndEvent):
document = self.compose_document()
# Ensure that the stream contains no more documents.
if not self.check_event(StreamEndEvent):
event = self.get_event()
raise ComposerError(
"expected a single document in the stream",
document.start_mark, "but found another document",
event.start_mark)
# Drop the STREAM-END event.
self.get_event()
return document
def compose_document(self):
# Drop the DOCUMENT-START event.
self.get_event()
# Compose the root node.
node = self.compose_node(None, None)
# Drop the DOCUMENT-END event.
self.get_event()
self.anchors = {}
return node
def compose_node(self, parent, index):
if self.check_event(AliasEvent):
event = self.get_event()
alias = event.anchor
if alias not in self.anchors:
raise ComposerError(
None, None, "found undefined alias %r"
% utf8(alias), event.start_mark)
return self.anchors[alias]
event = self.peek_event()
anchor = event.anchor
if anchor is not None: # have an anchor
if anchor in self.anchors:
raise ComposerError(
"found duplicate anchor %r; first occurence"
% utf8(anchor), self.anchors[anchor].start_mark,
"second occurence", event.start_mark)
self.descend_resolver(parent, index)
if self.check_event(ScalarEvent):
node = self.compose_scalar_node(anchor)
elif self.check_event(SequenceStartEvent):
node = self.compose_sequence_node(anchor)
elif self.check_event(MappingStartEvent):
node = self.compose_mapping_node(anchor)
self.ascend_resolver()
return node
def compose_scalar_node(self, anchor):
event = self.get_event()
tag = event.tag
if tag is None or tag == u'!':
tag = self.resolve(ScalarNode, event.value, event.implicit)
node = ScalarNode(tag, event.value,
event.start_mark, event.end_mark, style=event.style,
comment=event.comment)
if anchor is not None:
self.anchors[anchor] = node
return node
def compose_sequence_node(self, anchor):
start_event = self.get_event()
tag = start_event.tag
if tag is None or tag == u'!':
tag = self.resolve(SequenceNode, None, start_event.implicit)
node = SequenceNode(tag, [],
start_event.start_mark, None,
flow_style=start_event.flow_style,
comment=start_event.comment, anchor=anchor)
if anchor is not None:
self.anchors[anchor] = node
index = 0
while not self.check_event(SequenceEndEvent):
node.value.append(self.compose_node(node, index))
index += 1
end_event = self.get_event()
if node.flow_style is True and end_event.comment is not None:
if node.comment is not None:
print('Warning: unexpected end_event commment in sequence '
'node {}'.format(node.flow_style))
node.comment = end_event.comment
node.end_mark = end_event.end_mark
self.check_end_doc_comment(end_event, node)
return node
def compose_mapping_node(self, anchor):
start_event = self.get_event()
tag = start_event.tag
if tag is None or tag == u'!':
tag = self.resolve(MappingNode, None, start_event.implicit)
node = MappingNode(tag, [],
start_event.start_mark, None,
flow_style=start_event.flow_style,
comment=start_event.comment, anchor=anchor)
if anchor is not None:
self.anchors[anchor] = node
while not self.check_event(MappingEndEvent):
# key_event = self.peek_event()
item_key = self.compose_node(node, None)
# if item_key in node.value:
# raise ComposerError("while composing a mapping",
# start_event.start_mark,
# "found duplicate key", key_event.start_mark)
item_value = self.compose_node(node, item_key)
# node.value[item_key] = item_value
node.value.append((item_key, item_value))
end_event = self.get_event()
if node.flow_style is True and end_event.comment is not None:
node.comment = end_event.comment
node.end_mark = end_event.end_mark
self.check_end_doc_comment(end_event, node)
return node
def check_end_doc_comment(self, end_event, node):
if end_event.comment and end_event.comment[1]:
# pre comments on an end_event, no following to move to
if node.comment is None:
node.comment = [None, None]
assert not isinstance(node, ScalarEvent)
# this is a post comment on a mapping node, add as third element
# in the list
node.comment.append(end_event.comment[1])
end_event.comment[1] = None
|
