diff options
Diffstat (limited to 'powerline/lint/markedjson/constructor.py')
| -rw-r--r-- | powerline/lint/markedjson/constructor.py | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/powerline/lint/markedjson/constructor.py b/powerline/lint/markedjson/constructor.py new file mode 100644 index 0000000..372d84b --- /dev/null +++ b/powerline/lint/markedjson/constructor.py @@ -0,0 +1,285 @@ +# vim:fileencoding=utf-8:noet +from __future__ import (unicode_literals, division, absolute_import, print_function) + +import collections +import types + +from functools import wraps + +from powerline.lint.markedjson.error import MarkedError + +from powerline.lint.markedjson import nodes +from powerline.lint.markedjson.markedvalue import gen_marked_value +from powerline.lib.unicode import unicode + + +def marked(func): + @wraps(func) + def f(self, node, *args, **kwargs): + return gen_marked_value(func(self, node, *args, **kwargs), node.start_mark) + return f + + +class ConstructorError(MarkedError): + pass + + +class BaseConstructor: + yaml_constructors = {} + + def __init__(self): + self.constructed_objects = {} + self.state_generators = [] + self.deep_construct = False + + def check_data(self): + # If there are more documents available? + return self.check_node() + + def get_data(self): + # Construct and return the next document. + if self.check_node(): + return self.construct_document(self.get_node()) + + def get_single_data(self): + # Ensure that the stream contains a single document and construct it. + node = self.get_single_node() + if node is not None: + return self.construct_document(node) + return None + + def construct_document(self, node): + data = self.construct_object(node) + while self.state_generators: + state_generators = self.state_generators + self.state_generators = [] + for generator in state_generators: + for dummy in generator: + pass + self.constructed_objects = {} + self.deep_construct = False + return data + + def construct_object(self, node, deep=False): + if node in self.constructed_objects: + return self.constructed_objects[node] + if deep: + old_deep = self.deep_construct + self.deep_construct = True + constructor = None + tag_suffix = None + if node.tag in self.yaml_constructors: + constructor = self.yaml_constructors[node.tag] + else: + raise ConstructorError(None, None, 'no constructor for tag %s' % node.tag) + if tag_suffix is None: + data = constructor(self, node) + else: + data = constructor(self, tag_suffix, node) + if isinstance(data, types.GeneratorType): + generator = data + data = next(generator) + if self.deep_construct: + for dummy in generator: + pass + else: + self.state_generators.append(generator) + self.constructed_objects[node] = data + if deep: + self.deep_construct = old_deep + return data + + @marked + def construct_scalar(self, node): + if not isinstance(node, nodes.ScalarNode): + raise ConstructorError( + None, None, + 'expected a scalar node, but found %s' % node.id, + node.start_mark + ) + return node.value + + def construct_sequence(self, node, deep=False): + if not isinstance(node, nodes.SequenceNode): + raise ConstructorError( + None, None, + 'expected a sequence node, but found %s' % node.id, + node.start_mark + ) + return [ + self.construct_object(child, deep=deep) + for child in node.value + ] + + @marked + def construct_mapping(self, node, deep=False): + if not isinstance(node, nodes.MappingNode): + raise ConstructorError( + None, None, + 'expected a mapping node, but found %s' % node.id, + node.start_mark + ) + mapping = {} + for key_node, value_node in node.value: + key = self.construct_object(key_node, deep=deep) + if not isinstance(key, collections.abc.Hashable): + self.echoerr( + 'While constructing a mapping', node.start_mark, + 'found unhashable key', key_node.start_mark + ) + continue + elif type(key.value) != unicode: + self.echoerr( + 'Error while constructing a mapping', node.start_mark, + 'found key that is not a string', key_node.start_mark + ) + continue + elif key in mapping: + self.echoerr( + 'Error while constructing a mapping', node.start_mark, + 'found duplicate key', key_node.start_mark + ) + continue + value = self.construct_object(value_node, deep=deep) + mapping[key] = value + return mapping + + @classmethod + def add_constructor(cls, tag, constructor): + if 'yaml_constructors' not in cls.__dict__: + cls.yaml_constructors = cls.yaml_constructors.copy() + cls.yaml_constructors[tag] = constructor + + +class Constructor(BaseConstructor): + def construct_scalar(self, node): + if isinstance(node, nodes.MappingNode): + for key_node, value_node in node.value: + if key_node.tag == 'tag:yaml.org,2002:value': + return self.construct_scalar(value_node) + return BaseConstructor.construct_scalar(self, node) + + def flatten_mapping(self, node): + merge = [] + index = 0 + while index < len(node.value): + key_node, value_node = node.value[index] + if key_node.tag == 'tag:yaml.org,2002:merge': + del node.value[index] + if isinstance(value_node, nodes.MappingNode): + self.flatten_mapping(value_node) + merge.extend(value_node.value) + elif isinstance(value_node, nodes.SequenceNode): + submerge = [] + for subnode in value_node.value: + if not isinstance(subnode, nodes.MappingNode): + raise ConstructorError( + 'while constructing a mapping', + node.start_mark, + 'expected a mapping for merging, but found %s' % subnode.id, + subnode.start_mark + ) + self.flatten_mapping(subnode) + submerge.append(subnode.value) + submerge.reverse() + for value in submerge: + merge.extend(value) + else: + raise ConstructorError( + 'while constructing a mapping', + node.start_mark, + ('expected a mapping or list of mappings for merging, but found %s' % value_node.id), + value_node.start_mark + ) + elif key_node.tag == 'tag:yaml.org,2002:value': + key_node.tag = 'tag:yaml.org,2002:str' + index += 1 + else: + index += 1 + if merge: + node.value = merge + node.value + + def construct_mapping(self, node, deep=False): + if isinstance(node, nodes.MappingNode): + self.flatten_mapping(node) + return BaseConstructor.construct_mapping(self, node, deep=deep) + + @marked + def construct_yaml_null(self, node): + self.construct_scalar(node) + return None + + @marked + def construct_yaml_bool(self, node): + value = self.construct_scalar(node).value + return bool(value) + + @marked + def construct_yaml_int(self, node): + value = self.construct_scalar(node).value + sign = +1 + if value[0] == '-': + sign = -1 + if value[0] in '+-': + value = value[1:] + if value == '0': + return 0 + else: + return sign * int(value) + + @marked + def construct_yaml_float(self, node): + value = self.construct_scalar(node).value + sign = +1 + if value[0] == '-': + sign = -1 + if value[0] in '+-': + value = value[1:] + else: + return sign * float(value) + + def construct_yaml_str(self, node): + return self.construct_scalar(node) + + def construct_yaml_seq(self, node): + data = gen_marked_value([], node.start_mark) + yield data + data.extend(self.construct_sequence(node)) + + def construct_yaml_map(self, node): + data = gen_marked_value({}, node.start_mark) + yield data + value = self.construct_mapping(node) + data.update(value) + + def construct_undefined(self, node): + raise ConstructorError( + None, None, + 'could not determine a constructor for the tag %r' % node.tag, + node.start_mark + ) + + +Constructor.add_constructor( + 'tag:yaml.org,2002:null', Constructor.construct_yaml_null) + +Constructor.add_constructor( + 'tag:yaml.org,2002:bool', Constructor.construct_yaml_bool) + +Constructor.add_constructor( + 'tag:yaml.org,2002:int', Constructor.construct_yaml_int) + +Constructor.add_constructor( + 'tag:yaml.org,2002:float', Constructor.construct_yaml_float) + +Constructor.add_constructor( + 'tag:yaml.org,2002:str', Constructor.construct_yaml_str) + +Constructor.add_constructor( + 'tag:yaml.org,2002:seq', Constructor.construct_yaml_seq) + +Constructor.add_constructor( + 'tag:yaml.org,2002:map', Constructor.construct_yaml_map) + +Constructor.add_constructor( + None, Constructor.construct_undefined) |