netdata/python.d/python_modules/pyyaml2/emitter.py at master · jamesblunt/netdata · GitHub

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# Emitter expects events obeying the following grammar:

# stream ::= STREAM-START document* STREAM-END

# document ::= DOCUMENT-START node DOCUMENT-END

# node ::= SCALAR | sequence | mapping

# sequence ::= SEQUENCE-START node* SEQUENCE-END

# mapping ::= MAPPING-START (node node)* MAPPING-END

__all__ = ['Emitter', 'EmitterError']

from error import YAMLError

from events import *

class EmitterError(YAMLError):

pass

class ScalarAnalysis(object):

def __init__(self, scalar, empty, multiline,

allow_flow_plain, allow_block_plain,

allow_single_quoted, allow_double_quoted,

allow_block):

self.scalar = scalar

self.empty = empty

self.multiline = multiline

self.allow_flow_plain = allow_flow_plain

self.allow_block_plain = allow_block_plain

self.allow_single_quoted = allow_single_quoted

self.allow_double_quoted = allow_double_quoted

self.allow_block = allow_block

class Emitter(object):

DEFAULT_TAG_PREFIXES = {

u'!' : u'!',

u'tag:yaml.org,2002:' : u'!!',

}

def __init__(self, stream, canonical=None, indent=None, width=None,

allow_unicode=None, line_break=None):

# The stream should have the methods `write` and possibly `flush`.

self.stream = stream

# Encoding can be overriden by STREAM-START.

self.encoding = None

# Emitter is a state machine with a stack of states to handle nested

# structures.

self.states = []

self.state = self.expect_stream_start

# Current event and the event queue.

self.events = []

self.event = None

# The current indentation level and the stack of previous indents.

self.indents = []

self.indent = None

# Flow level.

self.flow_level = 0

# Contexts.

self.root_context = False

self.sequence_context = False

self.mapping_context = False

self.simple_key_context = False

# Characteristics of the last emitted character:

# - current position.

# - is it a whitespace?

# - is it an indention character

# (indentation space, '-', '?', or ':')?

self.line = 0

self.column = 0

self.whitespace = True

self.indention = True

# Whether the document requires an explicit document indicator

self.open_ended = False

# Formatting details.

self.canonical = canonical

self.allow_unicode = allow_unicode

self.best_indent = 2

if indent and 1 < indent < 10:

self.best_indent = indent

self.best_width = 80

if width and width > self.best_indent*2:

self.best_width = width

self.best_line_break = u'\n'

if line_break in [u'\r', u'\n', u'\r\n']:

self.best_line_break = line_break

# Tag prefixes.

self.tag_prefixes = None

# Prepared anchor and tag.

self.prepared_anchor = None

self.prepared_tag = None

# Scalar analysis and style.

self.analysis = None

self.style = None

def dispose(self):

# Reset the state attributes (to clear self-references)

self.states = []

self.state = None

def emit(self, event):

self.events.append(event)

while not self.need_more_events():

self.event = self.events.pop(0)

self.state()

self.event = None

# In some cases, we wait for a few next events before emitting.

def need_more_events(self):

if not self.events:

return True

event = self.events[0]

if isinstance(event, DocumentStartEvent):

return self.need_events(1)

elif isinstance(event, SequenceStartEvent):

return self.need_events(2)

elif isinstance(event, MappingStartEvent):

return self.need_events(3)

else:

return False

def need_events(self, count):

level = 0

for event in self.events[1:]:

if isinstance(event, (DocumentStartEvent, CollectionStartEvent)):

level += 1

elif isinstance(event, (DocumentEndEvent, CollectionEndEvent)):

level -= 1

elif isinstance(event, StreamEndEvent):

level = -1

if level < 0:

return False

return (len(self.events) < count+1)

def increase_indent(self, flow=False, indentless=False):

self.indents.append(self.indent)

if self.indent is None:

if flow:

self.indent = self.best_indent

else:

self.indent = 0

elif not indentless:

self.indent += self.best_indent

# States.

# Stream handlers.

def expect_stream_start(self):

if isinstance(self.event, StreamStartEvent):

if self.event.encoding and not getattr(self.stream, 'encoding', None):

self.encoding = self.event.encoding

self.write_stream_start()

self.state = self.expect_first_document_start

else:

raise EmitterError("expected StreamStartEvent, but got %s"

% self.event)

def expect_nothing(self):

raise EmitterError("expected nothing, but got %s" % self.event)

# Document handlers.

def expect_first_document_start(self):

return self.expect_document_start(first=True)

def expect_document_start(self, first=False):

if isinstance(self.event, DocumentStartEvent):

if (self.event.version or self.event.tags) and self.open_ended:

self.write_indicator(u'...', True)

self.write_indent()

if self.event.version:

version_text = self.prepare_version(self.event.version)

self.write_version_directive(version_text)

self.tag_prefixes = self.DEFAULT_TAG_PREFIXES.copy()

if self.event.tags:

handles = self.event.tags.keys()

handles.sort()

for handle in handles:

prefix = self.event.tags[handle]

self.tag_prefixes[prefix] = handle

handle_text = self.prepare_tag_handle(handle)

prefix_text = self.prepare_tag_prefix(prefix)

self.write_tag_directive(handle_text, prefix_text)

implicit = (first and not self.event.explicit and not self.canonical

and not self.event.version and not self.event.tags

and not self.check_empty_document())

if not implicit:

self.write_indent()

self.write_indicator(u'---', True)

if self.canonical:

self.write_indent()

self.state = self.expect_document_root

elif isinstance(self.event, StreamEndEvent):

if self.open_ended:

self.write_indicator(u'...', True)

self.write_indent()

self.write_stream_end()

self.state = self.expect_nothing

else:

raise EmitterError("expected DocumentStartEvent, but got %s"

% self.event)

def expect_document_end(self):

if isinstance(self.event, DocumentEndEvent):

self.write_indent()

if self.event.explicit:

self.write_indicator(u'...', True)

self.write_indent()

self.flush_stream()

self.state = self.expect_document_start

else:

raise EmitterError("expected DocumentEndEvent, but got %s"

% self.event)

def expect_document_root(self):

self.states.append(self.expect_document_end)

self.expect_node(root=True)

# Node handlers.

def expect_node(self, root=False, sequence=False, mapping=False,

simple_key=False):

self.root_context = root

self.sequence_context = sequence

self.mapping_context = mapping

self.simple_key_context = simple_key

if isinstance(self.event, AliasEvent):

self.expect_alias()

elif isinstance(self.event, (ScalarEvent, CollectionStartEvent)):

self.process_anchor(u'&')

self.process_tag()

if isinstance(self.event, ScalarEvent):

self.expect_scalar()

elif isinstance(self.event, SequenceStartEvent):

if self.flow_level or self.canonical or self.event.flow_style \

or self.check_empty_sequence():

self.expect_flow_sequence()

else:

self.expect_block_sequence()

elif isinstance(self.event, MappingStartEvent):

if self.flow_level or self.canonical or self.event.flow_style \

or self.check_empty_mapping():

self.expect_flow_mapping()

else:

self.expect_block_mapping()

else:

raise EmitterError("expected NodeEvent, but got %s" % self.event)

def expect_alias(self):

if self.event.anchor is None:

raise EmitterError("anchor is not specified for alias")

self.process_anchor(u'*')

self.state = self.states.pop()

def expect_scalar(self):

self.increase_indent(flow=True)

self.process_scalar()

self.indent = self.indents.pop()

self.state = self.states.pop()

# Flow sequence handlers.

def expect_flow_sequence(self):

self.write_indicator(u'[', True, whitespace=True)

self.flow_level += 1

self.increase_indent(flow=True)

self.state = self.expect_first_flow_sequence_item

def expect_first_flow_sequence_item(self):

if isinstance(self.event, SequenceEndEvent):

self.indent = self.indents.pop()

self.flow_level -= 1

self.write_indicator(u']', False)

self.state = self.states.pop()

else:

if self.canonical or self.column > self.best_width:

self.write_indent()

self.states.append(self.expect_flow_sequence_item)

self.expect_node(sequence=True)

def expect_flow_sequence_item(self):

if isinstance(self.event, SequenceEndEvent):

self.indent = self.indents.pop()

self.flow_level -= 1

if self.canonical:

self.write_indicator(u',', False)

self.write_indent()

self.write_indicator(u']', False)

self.state = self.states.pop()

else:

self.write_indicator(u',', False)

if self.canonical or self.column > self.best_width:

self.write_indent()

self.states.append(self.expect_flow_sequence_item)

self.expect_node(sequence=True)

# Flow mapping handlers.

def expect_flow_mapping(self):

self.write_indicator(u'{', True, whitespace=True)

self.flow_level += 1

self.increase_indent(flow=True)

self.state = self.expect_first_flow_mapping_key

def expect_first_flow_mapping_key(self):

if isinstance(self.event, MappingEndEvent):

self.indent = self.indents.pop()

self.flow_level -= 1

self.write_indicator(u'}', False)

self.state = self.states.pop()

else:

if self.canonical or self.column > self.best_width:

self.write_indent()

if not self.canonical and self.check_simple_key():

self.states.append(self.expect_flow_mapping_simple_value)

self.expect_node(mapping=True, simple_key=True)

else:

self.write_indicator(u'?', True)

self.states.append(self.expect_flow_mapping_value)

self.expect_node(mapping=True)

def expect_flow_mapping_key(self):

if isinstance(self.event, MappingEndEvent):

self.indent = self.indents.pop()

self.flow_level -= 1

if self.canonical:

self.write_indicator(u',', False)

self.write_indent()

self.write_indicator(u'}', False)

self.state = self.states.pop()

else:

self.write_indicator(u',', False)

if self.canonical or self.column > self.best_width:

self.write_indent()

if not self.canonical and self.check_simple_key():

self.states.append(self.expect_flow_mapping_simple_value)

self.expect_node(mapping=True, simple_key=True)

else:

self.write_indicator(u'?', True)

self.states.append(self.expect_flow_mapping_value)

self.expect_node(mapping=True)

def expect_flow_mapping_simple_value(self):

self.write_indicator(u':', False)

self.states.append(self.expect_flow_mapping_key)

self.expect_node(mapping=True)

def expect_flow_mapping_value(self):

if self.canonical or self.column > self.best_width:

self.write_indent()

self.write_indicator(u':', True)

self.states.append(self.expect_flow_mapping_key)

self.expect_node(mapping=True)

# Block sequence handlers.

def expect_block_sequence(self):

indentless = (self.mapping_context and not self.indention)

self.increase_indent(flow=False, indentless=indentless)

self.state = self.expect_first_block_sequence_item

def expect_first_block_sequence_item(self):

return self.expect_block_sequence_item(first=True)

def expect_block_sequence_item(self, first=False):

if not first and isinstance(self.event, SequenceEndEvent):

self.indent = self.indents.pop()

self.state = self.states.pop()

else:

self.write_indent()

self.write_indicator(u'-', True, indention=True)

self.states.append(self.expect_block_sequence_item)

self.expect_node(sequence=True)

# Block mapping handlers.

def expect_block_mapping(self):

self.increase_indent(flow=False)

self.state = self.expect_first_block_mapping_key

def expect_first_block_mapping_key(self):

return self.expect_block_mapping_key(first=True)

def expect_block_mapping_key(self, first=False):

if not first and isinstance(self.event, MappingEndEvent):

self.indent = self.indents.pop()

self.state = self.states.pop()

else:

self.write_indent()

if self.check_simple_key():

self.states.append(self.expect_block_mapping_simple_value)

self.expect_node(mapping=True, simple_key=True)

else:

self.write_indicator(u'?', True, indention=True)

self.states.append(self.expect_block_mapping_value)

self.expect_node(mapping=True)

def expect_block_mapping_simple_value(self):

self.write_indicator(u':', False)

self.states.append(self.expect_block_mapping_key)

self.expect_node(mapping=True)

def expect_block_mapping_value(self):

self.write_indent()

self.write_indicator(u':', True, indention=True)

self.states.append(self.expect_block_mapping_key)

self.expect_node(mapping=True)

# Checkers.

def check_empty_sequence(self):

return (isinstance(self.event, SequenceStartEvent) and self.events

and isinstance(self.events[0], SequenceEndEvent))

def check_empty_mapping(self):

return (isinstance(self.event, MappingStartEvent) and self.events

and isinstance(self.events[0], MappingEndEvent))

def check_empty_document(self):

if not isinstance(self.event, DocumentStartEvent) or not self.events:

return False

event = self.events[0]

return (isinstance(event, ScalarEvent) and event.anchor is None

and event.tag is None and event.implicit and event.value == u'')

def check_simple_key(self):

length = 0

if isinstance(self.event, NodeEvent) and self.event.anchor is not None:

if self.prepared_anchor is None:

self.prepared_anchor = self.prepare_anchor(self.event.anchor)

length += len(self.prepared_anchor)

if isinstance(self.event, (ScalarEvent, CollectionStartEvent)) \

and self.event.tag is not None:

if self.prepared_tag is None:

self.prepared_tag = self.prepare_tag(self.event.tag)

length += len(self.prepared_tag)

if isinstance(self.event, ScalarEvent):

if self.analysis is None:

self.analysis = self.analyze_scalar(self.event.value)

length += len(self.analysis.scalar)

return (length < 128 and (isinstance(self.event, AliasEvent)

or (isinstance(self.event, ScalarEvent)

and not self.analysis.empty and not self.analysis.multiline)

or self.check_empty_sequence() or self.check_empty_mapping()))

# Anchor, Tag, and Scalar processors.

def process_anchor(self, indicator):

if self.event.anchor is None:

self.prepared_anchor = None

return

if self.prepared_anchor is None:

self.prepared_anchor = self.prepare_anchor(self.event.anchor)

if self.prepared_anchor:

self.write_indicator(indicator+self.prepared_anchor, True)

self.prepared_anchor = None

def process_tag(self):

tag = self.event.tag

if isinstance(self.event, ScalarEvent):

if self.style is None:

self.style = self.choose_scalar_style()

if ((not self.canonical or tag is None) and

((self.style == '' and self.event.implicit[0])

or (self.style != '' and self.event.implicit[1]))):

self.prepared_tag = None

return

if self.event.implicit[0] and tag is None:

tag = u'!'

self.prepared_tag = None

else:

if (not self.canonical or tag is None) and self.event.implicit:

self.prepared_tag = None

return

if tag is None:

raise EmitterError("tag is not specified")

if self.prepared_tag is None:

self.prepared_tag = self.prepare_tag(tag)

if self.prepared_tag:

self.write_indicator(self.prepared_tag, True)

self.prepared_tag = None

def choose_scalar_style(self):

if self.analysis is None:

self.analysis = self.analyze_scalar(self.event.value)

if self.event.style == '"' or self.canonical:

return '"'

if not self.event.style and self.event.implicit[0]:

if (not (self.simple_key_context and

(self.analysis.empty or self.analysis.multiline))

and (self.flow_level and self.analysis.allow_flow_plain

or (not self.flow_level and self.analysis.allow_block_plain))):

return ''

if self.event.style and self.event.style in '|>':

if (not self.flow_level and not self.simple_key_context

and self.analysis.allow_block):

return self.event.style

if not self.event.style or self.event.style == '\'':

if (self.analysis.allow_single_quoted and

not (self.simple_key_context and self.analysis.multiline)):

return '\''

return '"'

def process_scalar(self):

if self.analysis is None:

self.analysis = self.analyze_scalar(self.event.value)

if self.style is None:

self.style = self.choose_scalar_style()

split = (not self.simple_key_context)

#if self.analysis.multiline and split \

# and (not self.style or self.style in '\'\"'):

# self.write_indent()

if self.style == '"':

self.write_double_quoted(self.analysis.scalar, split)

elif self.style == '\'':

self.write_single_quoted(self.analysis.scalar, split)

elif self.style == '>':

self.write_folded(self.analysis.scalar)

elif self.style == '|':

self.write_literal(self.analysis.scalar)

else:

self.write_plain(self.analysis.scalar, split)

self.analysis = None

self.style = None

# Analyzers.

def prepare_version(self, version):

major, minor = version

if major != 1:

raise EmitterError("unsupported YAML version: %d.%d" % (major, minor))

return u'%d.%d' % (major, minor)

def prepare_tag_handle(self, handle):

if not handle:

raise EmitterError("tag handle must not be empty")

if handle[0] != u'!' or handle[-1] != u'!':

raise EmitterError("tag handle must start and end with '!': %r"

% (handle.encode('utf-8')))

for ch in handle[1:-1]:

if not (u'0' <= ch <= u'9' or u'A' <= ch <= u'Z' or u'a' <= ch <= u'z' \

or ch in u'-_'):

raise EmitterError("invalid character %r in the tag handle: %r"

% (ch.encode('utf-8'), handle.encode('utf-8')))

return handle

def prepare_tag_prefix(self, prefix):

if not prefix:

raise EmitterError("tag prefix must not be empty")

chunks = []

start = end = 0

if prefix[0] == u'!':

end = 1

while end < len(prefix):

ch = prefix[end]

if u'0' <= ch <= u'9' or u'A' <= ch <= u'Z' or u'a' <= ch <= u'z' \

or ch in u'-;/?!:@&=+$,_.~*\'()[]':

end += 1

else:

if start < end:

chunks.append(prefix[start:end])

start = end = end+1

data = ch.encode('utf-8')

for ch in data:

chunks.append(u'%%%02X' % ord(ch))

if start < end:

chunks.append(prefix[start:end])

return u''.join(chunks)

def prepare_tag(self, tag):

if not tag:

raise EmitterError("tag must not be empty")

if tag == u'!':

return tag

handle = None

suffix = tag

prefixes = self.tag_prefixes.keys()

prefixes.sort()

for prefix in prefixes:

if tag.startswith(prefix) \

and (prefix == u'!' or len(prefix) < len(tag)):

handle = self.tag_prefixes[prefix]

suffix = tag[len(prefix):]

chunks = []

start = end = 0

while end < len(suffix):

ch = suffix[end]

if u'0' <= ch <= u'9' or u'A' <= ch <= u'Z' or u'a' <= ch <= u'z' \

or ch in u'-;/?:@&=+$,_.~*\'()[]' \

or (ch == u'!' and handle != u'!'):

end += 1

else:

if start < end:

chunks.append(suffix[start:end])

start = end = end+1

data = ch.encode('utf-8')

for ch in data:

chunks.append(u'%%%02X' % ord(ch))

if start < end:

chunks.append(suffix[start:end])

suffix_text = u''.join(chunks)

if handle:

return u'%s%s' % (handle, suffix_text)

else:

return u'!<%s>' % suffix_text

def prepare_anchor(self, anchor):

if not anchor:

raise EmitterError("anchor must not be empty")

for ch in anchor:

if not (u'0' <= ch <= u'9' or u'A' <= ch <= u'Z' or u'a' <= ch <= u'z' \

or ch in u'-_'):

raise EmitterError("invalid character %r in the anchor: %r"

% (ch.encode('utf-8'), anchor.encode('utf-8')))

return anchor

def analyze_scalar(self, scalar):

# Empty scalar is a special case.

if not scalar:

return ScalarAnalysis(scalar=scalar, empty=True, multiline=False,

allow_flow_plain=False, allow_block_plain=True,

allow_single_quoted=True, allow_double_quoted=True,

allow_block=False)

# Indicators and special characters.

block_indicators = False

flow_indicators = False

line_breaks = False

special_characters = False

# Important whitespace combinations.

leading_space = False

leading_break = False

trailing_space = False

trailing_break = False

break_space = False

space_break = False

# Check document indicators.

if scalar.startswith(u'---') or scalar.startswith(u'...'):

block_indicators = True

flow_indicators = True

# First character or preceded by a whitespace.

preceeded_by_whitespace = True

# Last character or followed by a whitespace.

followed_by_whitespace = (len(scalar) == 1 or

scalar[1] in u'\0 \t\r\n\x85\u2028\u2029')

# The previous character is a space.

previous_space = False

# The previous character is a break.

previous_break = False

index = 0

while index < len(scalar):

ch = scalar[index]

# Check for indicators.

if index == 0:

# Leading indicators are special characters.

if ch in u'#,[]{}&*!|>\'\"%@`':

flow_indicators = True

block_indicators = True

if ch in u'?:':

flow_indicators = True

if followed_by_whitespace:

block_indicators = True

if ch == u'-' and followed_by_whitespace:

flow_indicators = True

block_indicators = True

else:

# Some indicators cannot appear within a scalar as well.

if ch in u',?[]{}':

flow_indicators = True

if ch == u':':

flow_indicators = True

if followed_by_whitespace:

block_indicators = True

if ch == u'#' and preceeded_by_whitespace:

flow_indicators = True

block_indicators = True

# Check for line breaks, special, and unicode characters.

if ch in u'\n\x85\u2028\u2029':

line_breaks = True

if not (ch == u'\n' or u'\x20' <= ch <= u'\x7E'):

if (ch == u'\x85' or u'\xA0' <= ch <= u'\uD7FF'

or u'\uE000' <= ch <= u'\uFFFD') and ch != u'\uFEFF':

unicode_characters = True

if not self.allow_unicode:

special_characters = True

else:

special_characters = True

# Detect important whitespace combinations.

if ch == u' ':

if index == 0:

leading_space = True

if index == len(scalar)-1:

trailing_space = True

if previous_break:

break_space = True

previous_space = True

previous_break = False

elif ch in u'\n\x85\u2028\u2029':

if index == 0:

leading_break = True

if index == len(scalar)-1:

trailing_break = True

if previous_space:

space_break = True

previous_space = False

previous_break = True

else:

previous_space = False

previous_break = False

# Prepare for the next character.

index += 1

preceeded_by_whitespace = (ch in u'\0 \t\r\n\x85\u2028\u2029')

followed_by_whitespace = (index+1 >= len(scalar) or

scalar[index+1] in u'\0 \t\r\n\x85\u2028\u2029')

# Let's decide what styles are allowed.

allow_flow_plain = True

allow_block_plain = True

allow_single_quoted = True

allow_double_quoted = True

allow_block = True

# Leading and trailing whitespaces are bad for plain scalars.

if (leading_space or leading_break

or trailing_space or trailing_break):

allow_flow_plain = allow_block_plain = False

# We do not permit trailing spaces for block scalars.

if trailing_space:

allow_block = False

# Spaces at the beginning of a new line are only acceptable for block

# scalars.

if break_space:

allow_flow_plain = allow_block_plain = allow_single_quoted = False

# Spaces followed by breaks, as well as special character are only

# allowed for double quoted scalars.

if space_break or special_characters:

allow_flow_plain = allow_block_plain = \

allow_single_quoted = allow_block = False

# Although the plain scalar writer supports breaks, we never emit

# multiline plain scalars.

if line_breaks:

allow_flow_plain = allow_block_plain = False

# Flow indicators are forbidden for flow plain scalars.

if flow_indicators:

allow_flow_plain = False

# Block indicators are forbidden for block plain scalars.

if block_indicators:

allow_block_plain = False

return ScalarAnalysis(scalar=scalar,

empty=False, multiline=line_breaks,

allow_flow_plain=allow_flow_plain,

allow_block_plain=allow_block_plain,

allow_single_quoted=allow_single_quoted,

allow_double_quoted=allow_double_quoted,

allow_block=allow_block)

# Writers.

def flush_stream(self):

if hasattr(self.stream, 'flush'):

self.stream.flush()

def write_stream_start(self):

# Write BOM if needed.

if self.encoding and self.encoding.startswith('utf-16'):

self.stream.write(u'\uFEFF'.encode(self.encoding))

def write_stream_end(self):

self.flush_stream()

def write_indicator(self, indicator, need_whitespace,

whitespace=False, indention=False):

if self.whitespace or not need_whitespace:

data = indicator

else:

data = u' '+indicator

self.whitespace = whitespace

self.indention = self.indention and indention

self.column += len(data)

self.open_ended = False

if self.encoding:

data = data.encode(self.encoding)

self.stream.write(data)

def write_indent(self):

indent = self.indent or 0

if not self.indention or self.column > indent \

or (self.column == indent and not self.whitespace):

self.write_line_break()

if self.column < indent:

self.whitespace = True

data = u' '*(indent-self.column)

self.column = indent

if self.encoding:

data = data.encode(self.encoding)

self.stream.write(data)

def write_line_break(self, data=None):

if data is None:

data = self.best_line_break

self.whitespace = True

self.indention = True

self.line += 1

self.column = 0

if self.encoding:

data = data.encode(self.encoding)

self.stream.write(data)

def write_version_directive(self, version_text):

data = u'%%YAML %s' % version_text

if self.encoding:

data = data.encode(self.encoding)

self.stream.write(data)

self.write_line_break()

def write_tag_directive(self, handle_text, prefix_text):

data = u'%%TAG %s %s' % (handle_text, prefix_text)

if self.encoding:

data = data.encode(self.encoding)

self.stream.write(data)

self.write_line_break()

# Scalar streams.

def write_single_quoted(self, text, split=True):

self.write_indicator(u'\'', True)

spaces = False

breaks = False

start = end = 0

while end <= len(text):

ch = None

if end < len(text):

ch = text[end]

if spaces:

if ch is None or ch != u' ':

if start+1 == end and self.column > self.best_width and split \

and start != 0 and end != len(text):

self.write_indent()

else:

data = text[start:end]

self.column += len(data)

if self.encoding:

data = data.encode(self.encoding)

self.stream.write(data)

start = end

elif breaks:

if ch is None or ch not in u'\n\x85\u2028\u2029':

if text[start] == u'\n':

self.write_line_break()

for br in text[start:end]:

if br == u'\n':

self.write_line_break()

else:

self.write_line_break(br)

self.write_indent()

start = end

else:

if ch is None or ch in u' \n\x85\u2028\u2029' or ch == u'\'':

if start < end:

data = text[start:end]

self.column += len(data)

if self.encoding:

data = data.encode(self.encoding)

self.stream.write(data)

start = end

if ch == u'\'':

data = u'\'\''

self.column += 2

if self.encoding:

data = data.encode(self.encoding)

self.stream.write(data)

start = end + 1

if ch is not None:

spaces = (ch == u' ')

breaks = (ch in u'\n\x85\u2028\u2029')

end += 1

self.write_indicator(u'\'', False)

ESCAPE_REPLACEMENTS = {

u'\0': u'0',

u'\x07': u'a',

u'\x08': u'b',

u'\x09': u't',

u'\x0A': u'n',

u'\x0B': u'v',

u'\x0C': u'f',

u'\x0D': u'r',

u'\x1B': u'e',

u'\"': u'\"',

u'\\': u'\\',

u'\x85': u'N',

u'\xA0': u'_',

u'\u2028': u'L',

u'\u2029': u'P',

}

def write_double_quoted(self, text, split=True):

self.write_indicator(u'"', True)

start = end = 0

while end <= len(text):

ch = None

if end < len(text):

ch = text[end]

if ch is None or ch in u'"\\\x85\u2028\u2029\uFEFF' \

or not (u'\x20' <= ch <= u'\x7E'

or (self.allow_unicode

and (u'\xA0' <= ch <= u'\uD7FF'

or u'\uE000' <= ch <= u'\uFFFD'))):

if start < end:

data = text[start:end]

self.column += len(data)

if self.encoding:

data = data.encode(self.encoding)

self.stream.write(data)

start = end

if ch is not None:

if ch in self.ESCAPE_REPLACEMENTS:

data = u'\\'+self.ESCAPE_REPLACEMENTS[ch]

elif ch <= u'\xFF':

data = u'\\x%02X' % ord(ch)

elif ch <= u'\uFFFF':

data = u'\\u%04X' % ord(ch)

else:

data = u'\\U%08X' % ord(ch)

self.column += len(data)

if self.encoding:

data = data.encode(self.encoding)

self.stream.write(data)

start = end+1

if 0 < end < len(text)-1 and (ch == u' ' or start >= end) \

and self.column+(end-start) > self.best_width and split:

data = text[start:end]+u'\\'

if start < end:

start = end

self.column += len(data)

if self.encoding:

data = data.encode(self.encoding)

self.stream.write(data)

self.write_indent()

self.whitespace = False

self.indention = False

if text[start] == u' ':

data = u'\\'

self.column += len(data)

if self.encoding:

data = data.encode(self.encoding)

self.stream.write(data)

end += 1

self.write_indicator(u'"', False)

def determine_block_hints(self, text):

hints = u''

if text:

if text[0] in u' \n\x85\u2028\u2029':

hints += unicode(self.best_indent)

if text[-1] not in u'\n\x85\u2028\u2029':

hints += u'-'

elif len(text) == 1 or text[-2] in u'\n\x85\u2028\u2029':

hints += u'+'

return hints

def write_folded(self, text):

hints = self.determine_block_hints(text)

self.write_indicator(u'>'+hints, True)

if hints[-1:] == u'+':

self.open_ended = True

self.write_line_break()

leading_space = True

spaces = False

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netdata/python.d/python_modules/pyyaml2/emitter.py at master · jamesblunt/netdata · GitHub

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