Coverage for python/lsst/pex/config/dictField.py : 21%

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1# This file is part of pex_config.
2#
3# Developed for the LSST Data Management System.
4# This product includes software developed by the LSST Project
5# (http://www.lsst.org).
6# See the COPYRIGHT file at the top-level directory of this distribution
7# for details of code ownership.
8#
9# This software is dual licensed under the GNU General Public License and also
10# under a 3-clause BSD license. Recipients may choose which of these licenses
11# to use; please see the files gpl-3.0.txt and/or bsd_license.txt,
12# respectively. If you choose the GPL option then the following text applies
13# (but note that there is still no warranty even if you opt for BSD instead):
14#
15# This program is free software: you can redistribute it and/or modify
16# it under the terms of the GNU General Public License as published by
17# the Free Software Foundation, either version 3 of the License, or
18# (at your option) any later version.
19#
20# This program is distributed in the hope that it will be useful,
21# but WITHOUT ANY WARRANTY; without even the implied warranty of
22# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23# GNU General Public License for more details.
24#
25# You should have received a copy of the GNU General Public License
26# along with this program. If not, see <http://www.gnu.org/licenses/>.
28__all__ = ["DictField"]
30import collections.abc
32from .config import Field, FieldValidationError, _typeStr, _autocast, _joinNamePath
33from .comparison import getComparisonName, compareScalars
34from .callStack import getCallStack, getStackFrame
37class Dict(collections.abc.MutableMapping):
38 """An internal mapping container.
40 This class emulates a `dict`, but adds validation and provenance.
41 """
43 def __init__(self, config, field, value, at, label, setHistory=True):
44 self._field = field
45 self._config = config
46 self._dict = {}
47 self._history = self._config._history.setdefault(self._field.name, [])
48 self.__doc__ = field.doc
49 if value is not None:
50 try:
51 for k in value:
52 # do not set history per-item
53 self.__setitem__(k, value[k], at=at, label=label, setHistory=False)
54 except TypeError:
55 msg = "Value %s is of incorrect type %s. Mapping type expected." % \
56 (value, _typeStr(value))
57 raise FieldValidationError(self._field, self._config, msg)
58 if setHistory:
59 self._history.append((dict(self._dict), at, label))
61 history = property(lambda x: x._history) 61 ↛ exitline 61 didn't run the lambda on line 61
62 """History (read-only).
63 """
65 def __getitem__(self, k):
66 return self._dict[k]
68 def __len__(self):
69 return len(self._dict)
71 def __iter__(self):
72 return iter(self._dict)
74 def __contains__(self, k):
75 return k in self._dict
77 def __setitem__(self, k, x, at=None, label="setitem", setHistory=True):
78 if self._config._frozen:
79 msg = "Cannot modify a frozen Config. "\
80 "Attempting to set item at key %r to value %s" % (k, x)
81 raise FieldValidationError(self._field, self._config, msg)
83 # validate keytype
84 k = _autocast(k, self._field.keytype)
85 if type(k) != self._field.keytype:
86 msg = "Key %r is of type %s, expected type %s" % \
87 (k, _typeStr(k), _typeStr(self._field.keytype))
88 raise FieldValidationError(self._field, self._config, msg)
90 # validate itemtype
91 x = _autocast(x, self._field.itemtype)
92 if self._field.itemtype is None:
93 if type(x) not in self._field.supportedTypes and x is not None:
94 msg = "Value %s at key %r is of invalid type %s" % (x, k, _typeStr(x))
95 raise FieldValidationError(self._field, self._config, msg)
96 else:
97 if type(x) != self._field.itemtype and x is not None:
98 msg = "Value %s at key %r is of incorrect type %s. Expected type %s" % \
99 (x, k, _typeStr(x), _typeStr(self._field.itemtype))
100 raise FieldValidationError(self._field, self._config, msg)
102 # validate item using itemcheck
103 if self._field.itemCheck is not None and not self._field.itemCheck(x):
104 msg = "Item at key %r is not a valid value: %s" % (k, x)
105 raise FieldValidationError(self._field, self._config, msg)
107 if at is None:
108 at = getCallStack()
110 self._dict[k] = x
111 if setHistory:
112 self._history.append((dict(self._dict), at, label))
114 def __delitem__(self, k, at=None, label="delitem", setHistory=True):
115 if self._config._frozen:
116 raise FieldValidationError(self._field, self._config,
117 "Cannot modify a frozen Config")
119 del self._dict[k]
120 if setHistory:
121 if at is None:
122 at = getCallStack()
123 self._history.append((dict(self._dict), at, label))
125 def __repr__(self):
126 return repr(self._dict)
128 def __str__(self):
129 return str(self._dict)
131 def __setattr__(self, attr, value, at=None, label="assignment"):
132 if hasattr(getattr(self.__class__, attr, None), '__set__'):
133 # This allows properties to work.
134 object.__setattr__(self, attr, value)
135 elif attr in self.__dict__ or attr in ["_field", "_config", "_history", "_dict", "__doc__"]:
136 # This allows specific private attributes to work.
137 object.__setattr__(self, attr, value)
138 else:
139 # We throw everything else.
140 msg = "%s has no attribute %s" % (_typeStr(self._field), attr)
141 raise FieldValidationError(self._field, self._config, msg)
144class DictField(Field):
145 """A configuration field (`~lsst.pex.config.Field` subclass) that maps keys
146 and values.
148 The types of both items and keys are restricted to these builtin types:
149 `int`, `float`, `complex`, `bool`, and `str`). All keys share the same type
150 and all values share the same type. Keys can have a different type from
151 values.
153 Parameters
154 ----------
155 doc : `str`
156 A documentation string that describes the configuration field.
157 keytype : {`int`, `float`, `complex`, `bool`, `str`}
158 The type of the mapping keys. All keys must have this type.
159 itemtype : {`int`, `float`, `complex`, `bool`, `str`}
160 Type of the mapping values.
161 default : `dict`, optional
162 The default mapping.
163 optional : `bool`, optional
164 If `True`, the field doesn't need to have a set value.
165 dictCheck : callable
166 A function that validates the dictionary as a whole.
167 itemCheck : callable
168 A function that validates individual mapping values.
169 deprecated : None or `str`, optional
170 A description of why this Field is deprecated, including removal date.
171 If not None, the string is appended to the docstring for this Field.
173 See also
174 --------
175 ChoiceField
176 ConfigChoiceField
177 ConfigDictField
178 ConfigField
179 ConfigurableField
180 Field
181 ListField
182 RangeField
183 RegistryField
185 Examples
186 --------
187 This field maps has `str` keys and `int` values:
189 >>> from lsst.pex.config import Config, DictField
190 >>> class MyConfig(Config):
191 ... field = DictField(
192 ... doc="Example string-to-int mapping field.",
193 ... keytype=str, itemtype=int,
194 ... default={})
195 ...
196 >>> config = MyConfig()
197 >>> config.field['myKey'] = 42
198 >>> print(config.field)
199 {'myKey': 42}
200 """
202 DictClass = Dict
204 def __init__(self, doc, keytype, itemtype, default=None, optional=False, dictCheck=None, itemCheck=None,
205 deprecated=None):
206 source = getStackFrame()
207 self._setup(doc=doc, dtype=Dict, default=default, check=None,
208 optional=optional, source=source, deprecated=deprecated)
209 if keytype not in self.supportedTypes: 209 ↛ 210line 209 didn't jump to line 210, because the condition on line 209 was never true
210 raise ValueError("'keytype' %s is not a supported type" %
211 _typeStr(keytype))
212 elif itemtype is not None and itemtype not in self.supportedTypes: 212 ↛ 213line 212 didn't jump to line 213, because the condition on line 212 was never true
213 raise ValueError("'itemtype' %s is not a supported type" %
214 _typeStr(itemtype))
215 if dictCheck is not None and not hasattr(dictCheck, "__call__"): 215 ↛ 216line 215 didn't jump to line 216, because the condition on line 215 was never true
216 raise ValueError("'dictCheck' must be callable")
217 if itemCheck is not None and not hasattr(itemCheck, "__call__"): 217 ↛ 218line 217 didn't jump to line 218, because the condition on line 217 was never true
218 raise ValueError("'itemCheck' must be callable")
220 self.keytype = keytype
221 self.itemtype = itemtype
222 self.dictCheck = dictCheck
223 self.itemCheck = itemCheck
225 def validate(self, instance):
226 """Validate the field's value (for internal use only).
228 Parameters
229 ----------
230 instance : `lsst.pex.config.Config`
231 The configuration that contains this field.
233 Returns
234 -------
235 isValid : `bool`
236 `True` is returned if the field passes validation criteria (see
237 *Notes*). Otherwise `False`.
239 Notes
240 -----
241 This method validates values according to the following criteria:
243 - A non-optional field is not `None`.
244 - If a value is not `None`, is must pass the `ConfigField.dictCheck`
245 user callback functon.
247 Individual item checks by the `ConfigField.itemCheck` user callback
248 function are done immediately when the value is set on a key. Those
249 checks are not repeated by this method.
250 """
251 Field.validate(self, instance)
252 value = self.__get__(instance)
253 if value is not None and self.dictCheck is not None \
254 and not self.dictCheck(value):
255 msg = "%s is not a valid value" % str(value)
256 raise FieldValidationError(self, instance, msg)
258 def __set__(self, instance, value, at=None, label="assignment"):
259 if instance._frozen:
260 msg = "Cannot modify a frozen Config. "\
261 "Attempting to set field to value %s" % value
262 raise FieldValidationError(self, instance, msg)
264 if at is None:
265 at = getCallStack()
266 if value is not None:
267 value = self.DictClass(instance, self, value, at=at, label=label)
268 else:
269 history = instance._history.setdefault(self.name, [])
270 history.append((value, at, label))
272 instance._storage[self.name] = value
274 def toDict(self, instance):
275 """Convert this field's key-value pairs into a regular `dict`.
277 Parameters
278 ----------
279 instance : `lsst.pex.config.Config`
280 The configuration that contains this field.
282 Returns
283 -------
284 result : `dict` or `None`
285 If this field has a value of `None`, then this method returns
286 `None`. Otherwise, this method returns the field's value as a
287 regular Python `dict`.
288 """
289 value = self.__get__(instance)
290 return dict(value) if value is not None else None
292 def _compare(self, instance1, instance2, shortcut, rtol, atol, output):
293 """Compare two fields for equality.
295 Used by `lsst.pex.ConfigDictField.compare`.
297 Parameters
298 ----------
299 instance1 : `lsst.pex.config.Config`
300 Left-hand side config instance to compare.
301 instance2 : `lsst.pex.config.Config`
302 Right-hand side config instance to compare.
303 shortcut : `bool`
304 If `True`, this function returns as soon as an inequality if found.
305 rtol : `float`
306 Relative tolerance for floating point comparisons.
307 atol : `float`
308 Absolute tolerance for floating point comparisons.
309 output : callable
310 A callable that takes a string, used (possibly repeatedly) to
311 report inequalities.
313 Returns
314 -------
315 isEqual : bool
316 `True` if the fields are equal, `False` otherwise.
318 Notes
319 -----
320 Floating point comparisons are performed by `numpy.allclose`.
321 """
322 d1 = getattr(instance1, self.name)
323 d2 = getattr(instance2, self.name)
324 name = getComparisonName(
325 _joinNamePath(instance1._name, self.name),
326 _joinNamePath(instance2._name, self.name)
327 )
328 if not compareScalars("isnone for %s" % name, d1 is None, d2 is None, output=output):
329 return False
330 if d1 is None and d2 is None:
331 return True
332 if not compareScalars("keys for %s" % name, set(d1.keys()), set(d2.keys()), output=output):
333 return False
334 equal = True
335 for k, v1 in d1.items():
336 v2 = d2[k]
337 result = compareScalars("%s[%r]" % (name, k), v1, v2, dtype=self.itemtype,
338 rtol=rtol, atol=atol, output=output)
339 if not result and shortcut:
340 return False
341 equal = equal and result
342 return equal