# Copyright 2008-2015 Nokia Networks
# Copyright 2016- Robot Framework Foundation
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from ast import literal_eval
from collections import OrderedDict
from collections.abc import ByteString, Container, Mapping, Sequence, Set
from typing import Any, Union
from datetime import datetime, date, timedelta
from decimal import InvalidOperation, Decimal
from enum import Enum
from numbers import Integral, Real
from robot.libraries.DateTime import convert_date, convert_time
from robot.utils import (FALSE_STRINGS, TRUE_STRINGS, eq, get_error_message,
is_string, is_union, safe_str, seq2str, type_name)
NoneType = type(None)
[docs]class TypeConverter:
type = None
type_name = None
abc = None
aliases = ()
value_types = (str,)
doc = None
_converters = OrderedDict()
_type_aliases = {}
def __init__(self, used_type, custom_converters=None):
self.used_type = used_type
self.custom_converters = custom_converters
[docs] @classmethod
def register(cls, converter):
cls._converters[converter.type] = converter
for name in (converter.type_name,) + converter.aliases:
if name is not None and not isinstance(name, property):
cls._type_aliases[name.lower()] = converter.type
return converter
[docs] @classmethod
def converter_for(cls, type_, custom_converters=None):
try:
hash(type_)
except TypeError:
return None
if getattr(type_, '__origin__', None) and type_.__origin__ is not Union:
type_ = type_.__origin__
if isinstance(type_, str):
try:
type_ = cls._type_aliases[type_.lower()]
except KeyError:
return None
if custom_converters:
info = custom_converters.get_converter_info(type_)
if info:
return CustomConverter(type_, info)
if type_ in cls._converters:
return cls._converters[type_](type_)
for converter in cls._converters.values():
if converter.handles(type_):
return converter(type_, custom_converters)
return None
[docs] @classmethod
def handles(cls, type_):
handled = (cls.type, cls.abc) if cls.abc else cls.type
return isinstance(type_, type) and issubclass(type_, handled)
[docs] def convert(self, name, value, explicit_type=True, strict=True):
if self.no_conversion_needed(value):
return value
if not self._handles_value(value):
return self._handle_error(name, value, strict=strict)
try:
if not isinstance(value, str):
return self._non_string_convert(value, explicit_type)
return self._convert(value, explicit_type)
except ValueError as error:
return self._handle_error(name, value, error, strict)
[docs] def no_conversion_needed(self, value):
try:
return isinstance(value, self.used_type)
except TypeError:
# If the used type doesn't like `isinstance` (e.g. TypedDict),
# compare the value to the generic type instead.
if self.type and self.type is not self.used_type:
return isinstance(value, self.type)
raise
def _handles_value(self, value):
return isinstance(value, self.value_types)
def _non_string_convert(self, value, explicit_type=True):
return self._convert(value, explicit_type)
def _convert(self, value, explicit_type=True):
raise NotImplementedError
def _handle_error(self, name, value, error=None, strict=True):
if not strict:
return value
value_type = '' if isinstance(value, str) else f' ({type_name(value)})'
ending = f': {error}' if (error and error.args) else '.'
raise ValueError(
f"Argument '{name}' got value '{safe_str(value)}'{value_type} that "
f"cannot be converted to {self.type_name}{ending}"
)
def _literal_eval(self, value, expected):
if expected is set and value == 'set()':
# `ast.literal_eval` has no way to define an empty set.
return set()
try:
value = literal_eval(value)
except (ValueError, SyntaxError):
# Original errors aren't too informative in these cases.
raise ValueError('Invalid expression.')
except TypeError as err:
raise ValueError(f'Evaluating expression failed: {err}')
if not isinstance(value, expected):
raise ValueError(f'Value is {type_name(value)}, not {expected.__name__}.')
return value
def _remove_number_separators(self, value):
if is_string(value):
for sep in ' ', '_':
if sep in value:
value = value.replace(sep, '')
return value
[docs]@TypeConverter.register
class EnumConverter(TypeConverter):
type = Enum
@property
def type_name(self):
return self.used_type.__name__
@property
def value_types(self):
return (str, int) if issubclass(self.used_type, int) else (str,)
def _convert(self, value, explicit_type=True):
enum = self.used_type
if isinstance(value, int):
return self._find_by_int_value(enum, value)
try:
return enum[value]
except KeyError:
return self._find_by_normalized_name_or_int_value(enum, value)
def _find_by_normalized_name_or_int_value(self, enum, value):
members = sorted(enum.__members__)
matches = [m for m in members if eq(m, value, ignore='_')]
if len(matches) == 1:
return getattr(enum, matches[0])
if len(matches) > 1:
raise ValueError(f"{self.type_name} has multiple members matching "
f"'{value}'. Available: {seq2str(matches)}")
try:
if issubclass(self.used_type, int):
return self._find_by_int_value(enum, value)
except ValueError:
members = [f'{m} ({getattr(enum, m)})' for m in members]
raise ValueError(f"{self.type_name} does not have member '{value}'. "
f"Available: {seq2str(members)}")
def _find_by_int_value(self, enum, value):
value = int(value)
for member in enum:
if member.value == value:
return member
values = sorted(member.value for member in enum)
raise ValueError(f"{self.type_name} does not have value '{value}'. "
f"Available: {seq2str(values)}")
[docs]@TypeConverter.register
class StringConverter(TypeConverter):
type = str
type_name = 'string'
aliases = ('string', 'str', 'unicode')
value_types = (Any,)
def _handles_value(self, value):
return True
def _convert(self, value, explicit_type=True):
if not explicit_type:
return value
try:
return str(value)
except Exception:
raise ValueError(get_error_message())
[docs]@TypeConverter.register
class BooleanConverter(TypeConverter):
type = bool
type_name = 'boolean'
aliases = ('bool',)
value_types = (str, int, float, NoneType)
def _non_string_convert(self, value, explicit_type=True):
return value
def _convert(self, value, explicit_type=True):
upper = value.upper()
if upper == 'NONE':
return None
if upper in TRUE_STRINGS:
return True
if upper in FALSE_STRINGS:
return False
return value
[docs]@TypeConverter.register
class IntegerConverter(TypeConverter):
type = int
abc = Integral
type_name = 'integer'
aliases = ('int', 'long')
value_types = (str, float)
def _non_string_convert(self, value, explicit_type=True):
if value.is_integer():
return int(value)
raise ValueError('Conversion would lose precision.')
def _convert(self, value, explicit_type=True):
value = self._remove_number_separators(value)
value, base = self._get_base(value)
try:
return int(value, base)
except ValueError:
if base == 10 and not explicit_type:
try:
return float(value)
except ValueError:
pass
raise ValueError
def _get_base(self, value):
value = value.lower()
for prefix, base in [('0x', 16), ('0o', 8), ('0b', 2)]:
if prefix in value:
parts = value.split(prefix)
if len(parts) == 2 and parts[0] in ('', '-', '+'):
return ''.join(parts), base
return value, 10
[docs]@TypeConverter.register
class FloatConverter(TypeConverter):
type = float
abc = Real
type_name = 'float'
aliases = ('double',)
value_types = (str, Real)
def _convert(self, value, explicit_type=True):
try:
return float(self._remove_number_separators(value))
except ValueError:
raise ValueError
[docs]@TypeConverter.register
class DecimalConverter(TypeConverter):
type = Decimal
type_name = 'decimal'
value_types = (str, int, float)
def _convert(self, value, explicit_type=True):
try:
return Decimal(self._remove_number_separators(value))
except InvalidOperation:
# With Python 3 error messages by decimal module are not very
# useful and cannot be included in our error messages:
# https://bugs.python.org/issue26208
raise ValueError
[docs]@TypeConverter.register
class BytesConverter(TypeConverter):
type = bytes
abc = ByteString
type_name = 'bytes'
value_types = (str, bytearray)
def _non_string_convert(self, value, explicit_type=True):
return bytes(value)
def _convert(self, value, explicit_type=True):
try:
return value.encode('latin-1')
except UnicodeEncodeError as err:
invalid = value[err.start:err.start+1]
raise ValueError(f"Character '{invalid}' cannot be mapped to a byte.")
[docs]@TypeConverter.register
class ByteArrayConverter(TypeConverter):
type = bytearray
type_name = 'bytearray'
value_types = (str, bytes)
def _non_string_convert(self, value, explicit_type=True):
return bytearray(value)
def _convert(self, value, explicit_type=True):
try:
return bytearray(value, 'latin-1')
except UnicodeEncodeError as err:
invalid = value[err.start:err.start+1]
raise ValueError(f"Character '{invalid}' cannot be mapped to a byte.")
[docs]@TypeConverter.register
class DateTimeConverter(TypeConverter):
type = datetime
type_name = 'datetime'
value_types = (str, int, float)
def _convert(self, value, explicit_type=True):
return convert_date(value, result_format='datetime')
[docs]@TypeConverter.register
class DateConverter(TypeConverter):
type = date
type_name = 'date'
def _convert(self, value, explicit_type=True):
dt = convert_date(value, result_format='datetime')
if dt.hour or dt.minute or dt.second or dt.microsecond:
raise ValueError("Value is datetime, not date.")
return dt.date()
[docs]@TypeConverter.register
class TimeDeltaConverter(TypeConverter):
type = timedelta
type_name = 'timedelta'
value_types = (str, int, float)
def _convert(self, value, explicit_type=True):
return convert_time(value, result_format='timedelta')
[docs]@TypeConverter.register
class NoneConverter(TypeConverter):
type = NoneType
type_name = 'None'
[docs] @classmethod
def handles(cls, type_):
return type_ in (NoneType, None)
def _convert(self, value, explicit_type=True):
if value.upper() == 'NONE':
return None
raise ValueError
[docs]@TypeConverter.register
class ListConverter(TypeConverter):
type = list
type_name = 'list'
abc = Sequence
value_types = (str, Sequence)
[docs] def no_conversion_needed(self, value):
if isinstance(value, str):
return False
return super().no_conversion_needed(value)
def _non_string_convert(self, value, explicit_type=True):
return list(value)
def _convert(self, value, explicit_type=True):
return self._literal_eval(value, list)
[docs]@TypeConverter.register
class TupleConverter(TypeConverter):
type = tuple
type_name = 'tuple'
value_types = (str, Sequence)
def _non_string_convert(self, value, explicit_type=True):
return tuple(value)
def _convert(self, value, explicit_type=True):
return self._literal_eval(value, tuple)
[docs]@TypeConverter.register
class DictionaryConverter(TypeConverter):
type = dict
abc = Mapping
type_name = 'dictionary'
aliases = ('dict', 'map')
value_types = (str, Mapping)
def _non_string_convert(self, value, explicit_type=True):
if issubclass(self.used_type, dict) and not isinstance(value, dict):
return dict(value)
return value
def _convert(self, value, explicit_type=True):
return self._literal_eval(value, dict)
[docs]@TypeConverter.register
class SetConverter(TypeConverter):
type = set
abc = Set
type_name = 'set'
value_types = (str, Container)
def _non_string_convert(self, value, explicit_type=True):
return set(value)
def _convert(self, value, explicit_type=True):
return self._literal_eval(value, set)
[docs]@TypeConverter.register
class FrozenSetConverter(TypeConverter):
type = frozenset
type_name = 'frozenset'
value_types = (str, Container)
def _non_string_convert(self, value, explicit_type=True):
return frozenset(value)
def _convert(self, value, explicit_type=True):
# There are issues w/ literal_eval. See self._literal_eval for details.
if value == 'frozenset()':
return frozenset()
return frozenset(self._literal_eval(value, set))
[docs]@TypeConverter.register
class CombinedConverter(TypeConverter):
type = Union
def __init__(self, union, custom_converters):
super().__init__(self._get_types(union))
self.converters = [TypeConverter.converter_for(t, custom_converters)
for t in self.used_type]
def _get_types(self, union):
if not union:
return ()
if isinstance(union, tuple):
return union
return union.__args__
@property
def type_name(self):
return ' or '.join(type_name(t) for t in self.used_type)
[docs] @classmethod
def handles(cls, type_):
return is_union(type_, allow_tuple=True)
def _handles_value(self, value):
return True
[docs] def no_conversion_needed(self, value):
for converter in self.converters:
if converter and converter.no_conversion_needed(value):
return True
return False
def _convert(self, value, explicit_type=True):
for converter in self.converters:
if not converter:
return value
try:
return converter.convert('', value, explicit_type)
except ValueError:
pass
raise ValueError
[docs]class CustomConverter(TypeConverter):
def __init__(self, used_type, converter_info):
super().__init__(used_type)
self.converter_info = converter_info
@property
def type_name(self):
return self.converter_info.name
@property
def doc(self):
return self.converter_info.doc
@property
def value_types(self):
return self.converter_info.value_types
def _handles_value(self, value):
return not self.value_types or isinstance(value, self.value_types)
def _convert(self, value, explicit_type=True):
try:
return self.converter_info.converter(value)
except ValueError:
raise
except Exception:
raise ValueError(get_error_message())