PraBlatt3

venv/lib/python3.7/site-packages/django/contrib/postgres/fields/__init__.py

@@ -0,0 +1,5 @@
+from .array import *  # NOQA
+from .citext import *  # NOQA
+from .hstore import *  # NOQA
+from .jsonb import *  # NOQA
+from .ranges import *  # NOQA

venv/lib/python3.7/site-packages/django/contrib/postgres/fields/array.py

@@ -0,0 +1,305 @@
+import json
+
+from django.contrib.postgres import lookups
+from django.contrib.postgres.forms import SimpleArrayField
+from django.contrib.postgres.validators import ArrayMaxLengthValidator
+from django.core import checks, exceptions
+from django.db.models import Field, IntegerField, Transform
+from django.db.models.lookups import Exact, In
+from django.utils.inspect import func_supports_parameter
+from django.utils.translation import gettext_lazy as _
+
+from ..utils import prefix_validation_error
+from .mixins import CheckFieldDefaultMixin
+from .utils import AttributeSetter
+
+__all__ = ['ArrayField']
+
+
+class ArrayField(CheckFieldDefaultMixin, Field):
+    empty_strings_allowed = False
+    default_error_messages = {
+        'item_invalid': _('Item %(nth)s in the array did not validate:'),
+        'nested_array_mismatch': _('Nested arrays must have the same length.'),
+    }
+    _default_hint = ('list', '[]')
+
+    def __init__(self, base_field, size=None, **kwargs):
+        self.base_field = base_field
+        self.size = size
+        if self.size:
+            self.default_validators = [*self.default_validators, ArrayMaxLengthValidator(self.size)]
+        # For performance, only add a from_db_value() method if the base field
+        # implements it.
+        if hasattr(self.base_field, 'from_db_value'):
+            self.from_db_value = self._from_db_value
+        super().__init__(**kwargs)
+
+    @property
+    def model(self):
+        try:
+            return self.__dict__['model']
+        except KeyError:
+            raise AttributeError("'%s' object has no attribute 'model'" % self.__class__.__name__)
+
+    @model.setter
+    def model(self, model):
+        self.__dict__['model'] = model
+        self.base_field.model = model
+
+    def check(self, **kwargs):
+        errors = super().check(**kwargs)
+        if self.base_field.remote_field:
+            errors.append(
+                checks.Error(
+                    'Base field for array cannot be a related field.',
+                    obj=self,
+                    id='postgres.E002'
+                )
+            )
+        else:
+            # Remove the field name checks as they are not needed here.
+            base_errors = self.base_field.check()
+            if base_errors:
+                messages = '\n    '.join('%s (%s)' % (error.msg, error.id) for error in base_errors)
+                errors.append(
+                    checks.Error(
+                        'Base field for array has errors:\n    %s' % messages,
+                        obj=self,
+                        id='postgres.E001'
+                    )
+                )
+        return errors
+
+    def set_attributes_from_name(self, name):
+        super().set_attributes_from_name(name)
+        self.base_field.set_attributes_from_name(name)
+
+    @property
+    def description(self):
+        return 'Array of %s' % self.base_field.description
+
+    def db_type(self, connection):
+        size = self.size or ''
+        return '%s[%s]' % (self.base_field.db_type(connection), size)
+
+    def get_placeholder(self, value, compiler, connection):
+        return '%s::{}'.format(self.db_type(connection))
+
+    def get_db_prep_value(self, value, connection, prepared=False):
+        if isinstance(value, (list, tuple)):
+            return [self.base_field.get_db_prep_value(i, connection, prepared=False) for i in value]
+        return value
+
+    def deconstruct(self):
+        name, path, args, kwargs = super().deconstruct()
+        if path == 'django.contrib.postgres.fields.array.ArrayField':
+            path = 'django.contrib.postgres.fields.ArrayField'
+        kwargs.update({
+            'base_field': self.base_field.clone(),
+            'size': self.size,
+        })
+        return name, path, args, kwargs
+
+    def to_python(self, value):
+        if isinstance(value, str):
+            # Assume we're deserializing
+            vals = json.loads(value)
+            value = [self.base_field.to_python(val) for val in vals]
+        return value
+
+    def _from_db_value(self, value, expression, connection):
+        if value is None:
+            return value
+        return [
+            self.base_field.from_db_value(item, expression, connection, {})
+            if func_supports_parameter(self.base_field.from_db_value, 'context')  # RemovedInDjango30Warning
+            else self.base_field.from_db_value(item, expression, connection)
+            for item in value
+        ]
+
+    def value_to_string(self, obj):
+        values = []
+        vals = self.value_from_object(obj)
+        base_field = self.base_field
+
+        for val in vals:
+            if val is None:
+                values.append(None)
+            else:
+                obj = AttributeSetter(base_field.attname, val)
+                values.append(base_field.value_to_string(obj))
+        return json.dumps(values)
+
+    def get_transform(self, name):
+        transform = super().get_transform(name)
+        if transform:
+            return transform
+        if '_' not in name:
+            try:
+                index = int(name)
+            except ValueError:
+                pass
+            else:
+                index += 1  # postgres uses 1-indexing
+                return IndexTransformFactory(index, self.base_field)
+        try:
+            start, end = name.split('_')
+            start = int(start) + 1
+            end = int(end)  # don't add one here because postgres slices are weird
+        except ValueError:
+            pass
+        else:
+            return SliceTransformFactory(start, end)
+
+    def validate(self, value, model_instance):
+        super().validate(value, model_instance)
+        for index, part in enumerate(value):
+            try:
+                self.base_field.validate(part, model_instance)
+            except exceptions.ValidationError as error:
+                raise prefix_validation_error(
+                    error,
+                    prefix=self.error_messages['item_invalid'],
+                    code='item_invalid',
+                    params={'nth': index + 1},
+                )
+        if isinstance(self.base_field, ArrayField):
+            if len({len(i) for i in value}) > 1:
+                raise exceptions.ValidationError(
+                    self.error_messages['nested_array_mismatch'],
+                    code='nested_array_mismatch',
+                )
+
+    def run_validators(self, value):
+        super().run_validators(value)
+        for index, part in enumerate(value):
+            try:
+                self.base_field.run_validators(part)
+            except exceptions.ValidationError as error:
+                raise prefix_validation_error(
+                    error,
+                    prefix=self.error_messages['item_invalid'],
+                    code='item_invalid',
+                    params={'nth': index + 1},
+                )
+
+    def formfield(self, **kwargs):
+        return super().formfield(**{
+            'form_class': SimpleArrayField,
+            'base_field': self.base_field.formfield(),
+            'max_length': self.size,
+            **kwargs,
+        })
+
+
+@ArrayField.register_lookup
+class ArrayContains(lookups.DataContains):
+    def as_sql(self, qn, connection):
+        sql, params = super().as_sql(qn, connection)
+        sql = '%s::%s' % (sql, self.lhs.output_field.db_type(connection))
+        return sql, params
+
+
+@ArrayField.register_lookup
+class ArrayContainedBy(lookups.ContainedBy):
+    def as_sql(self, qn, connection):
+        sql, params = super().as_sql(qn, connection)
+        sql = '%s::%s' % (sql, self.lhs.output_field.db_type(connection))
+        return sql, params
+
+
+@ArrayField.register_lookup
+class ArrayExact(Exact):
+    def as_sql(self, qn, connection):
+        sql, params = super().as_sql(qn, connection)
+        sql = '%s::%s' % (sql, self.lhs.output_field.db_type(connection))
+        return sql, params
+
+
+@ArrayField.register_lookup
+class ArrayOverlap(lookups.Overlap):
+    def as_sql(self, qn, connection):
+        sql, params = super().as_sql(qn, connection)
+        sql = '%s::%s' % (sql, self.lhs.output_field.db_type(connection))
+        return sql, params
+
+
+@ArrayField.register_lookup
+class ArrayLenTransform(Transform):
+    lookup_name = 'len'
+    output_field = IntegerField()
+
+    def as_sql(self, compiler, connection):
+        lhs, params = compiler.compile(self.lhs)
+        # Distinguish NULL and empty arrays
+        return (
+            'CASE WHEN %(lhs)s IS NULL THEN NULL ELSE '
+            'coalesce(array_length(%(lhs)s, 1), 0) END'
+        ) % {'lhs': lhs}, params
+
+
+@ArrayField.register_lookup
+class ArrayInLookup(In):
+    def get_prep_lookup(self):
+        values = super().get_prep_lookup()
+        if hasattr(self.rhs, '_prepare'):
+            # Subqueries don't need further preparation.
+            return values
+        # In.process_rhs() expects values to be hashable, so convert lists
+        # to tuples.
+        prepared_values = []
+        for value in values:
+            if hasattr(value, 'resolve_expression'):
+                prepared_values.append(value)
+            else:
+                prepared_values.append(tuple(value))
+        return prepared_values
+
+
+class IndexTransform(Transform):
+
+    def __init__(self, index, base_field, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.index = index
+        self.base_field = base_field
+
+    def as_sql(self, compiler, connection):
+        lhs, params = compiler.compile(self.lhs)
+        return '%s[%s]' % (lhs, self.index), params
+
+    @property
+    def output_field(self):
+        return self.base_field
+
+
+class IndexTransformFactory:
+
+    def __init__(self, index, base_field):
+        self.index = index
+        self.base_field = base_field
+
+    def __call__(self, *args, **kwargs):
+        return IndexTransform(self.index, self.base_field, *args, **kwargs)
+
+
+class SliceTransform(Transform):
+
+    def __init__(self, start, end, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.start = start
+        self.end = end
+
+    def as_sql(self, compiler, connection):
+        lhs, params = compiler.compile(self.lhs)
+        return '%s[%s:%s]' % (lhs, self.start, self.end), params
+
+
+class SliceTransformFactory:
+
+    def __init__(self, start, end):
+        self.start = start
+        self.end = end
+
+    def __call__(self, *args, **kwargs):
+        return SliceTransform(self.start, self.end, *args, **kwargs)

venv/lib/python3.7/site-packages/django/contrib/postgres/fields/citext.py

@@ -0,0 +1,24 @@
+from django.db.models import CharField, EmailField, TextField
+
+__all__ = ['CICharField', 'CIEmailField', 'CIText', 'CITextField']
+
+
+class CIText:
+
+    def get_internal_type(self):
+        return 'CI' + super().get_internal_type()
+
+    def db_type(self, connection):
+        return 'citext'
+
+
+class CICharField(CIText, CharField):
+    pass
+
+
+class CIEmailField(CIText, EmailField):
+    pass
+
+
+class CITextField(CIText, TextField):
+    pass

venv/lib/python3.7/site-packages/django/contrib/postgres/fields/hstore.py

@@ -0,0 +1,112 @@
+import json
+
+from django.contrib.postgres import forms, lookups
+from django.contrib.postgres.fields.array import ArrayField
+from django.core import exceptions
+from django.db.models import Field, TextField, Transform
+from django.utils.translation import gettext_lazy as _
+
+from .mixins import CheckFieldDefaultMixin
+
+__all__ = ['HStoreField']
+
+
+class HStoreField(CheckFieldDefaultMixin, Field):
+    empty_strings_allowed = False
+    description = _('Map of strings to strings/nulls')
+    default_error_messages = {
+        'not_a_string': _('The value of "%(key)s" is not a string or null.'),
+    }
+    _default_hint = ('dict', '{}')
+
+    def db_type(self, connection):
+        return 'hstore'
+
+    def get_transform(self, name):
+        transform = super().get_transform(name)
+        if transform:
+            return transform
+        return KeyTransformFactory(name)
+
+    def validate(self, value, model_instance):
+        super().validate(value, model_instance)
+        for key, val in value.items():
+            if not isinstance(val, str) and val is not None:
+                raise exceptions.ValidationError(
+                    self.error_messages['not_a_string'],
+                    code='not_a_string',
+                    params={'key': key},
+                )
+
+    def to_python(self, value):
+        if isinstance(value, str):
+            value = json.loads(value)
+        return value
+
+    def value_to_string(self, obj):
+        return json.dumps(self.value_from_object(obj))
+
+    def formfield(self, **kwargs):
+        return super().formfield(**{
+            'form_class': forms.HStoreField,
+            **kwargs,
+        })
+
+    def get_prep_value(self, value):
+        value = super().get_prep_value(value)
+
+        if isinstance(value, dict):
+            prep_value = {}
+            for key, val in value.items():
+                key = str(key)
+                if val is not None:
+                    val = str(val)
+                prep_value[key] = val
+            value = prep_value
+
+        if isinstance(value, list):
+            value = [str(item) for item in value]
+
+        return value
+
+
+HStoreField.register_lookup(lookups.DataContains)
+HStoreField.register_lookup(lookups.ContainedBy)
+HStoreField.register_lookup(lookups.HasKey)
+HStoreField.register_lookup(lookups.HasKeys)
+HStoreField.register_lookup(lookups.HasAnyKeys)
+
+
+class KeyTransform(Transform):
+    output_field = TextField()
+
+    def __init__(self, key_name, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.key_name = key_name
+
+    def as_sql(self, compiler, connection):
+        lhs, params = compiler.compile(self.lhs)
+        return '(%s -> %%s)' % lhs, tuple(params) + (self.key_name,)
+
+
+class KeyTransformFactory:
+
+    def __init__(self, key_name):
+        self.key_name = key_name
+
+    def __call__(self, *args, **kwargs):
+        return KeyTransform(self.key_name, *args, **kwargs)
+
+
+@HStoreField.register_lookup
+class KeysTransform(Transform):
+    lookup_name = 'keys'
+    function = 'akeys'
+    output_field = ArrayField(TextField())
+
+
+@HStoreField.register_lookup
+class ValuesTransform(Transform):
+    lookup_name = 'values'
+    function = 'avals'
+    output_field = ArrayField(TextField())

venv/lib/python3.7/site-packages/django/contrib/postgres/fields/jsonb.py

@@ -0,0 +1,186 @@
+import json
+
+from psycopg2.extras import Json
+
+from django.contrib.postgres import forms, lookups
+from django.core import exceptions
+from django.db.models import (
+    Field, TextField, Transform, lookups as builtin_lookups,
+)
+from django.utils.translation import gettext_lazy as _
+
+from .mixins import CheckFieldDefaultMixin
+
+__all__ = ['JSONField']
+
+
+class JsonAdapter(Json):
+    """
+    Customized psycopg2.extras.Json to allow for a custom encoder.
+    """
+    def __init__(self, adapted, dumps=None, encoder=None):
+        self.encoder = encoder
+        super().__init__(adapted, dumps=dumps)
+
+    def dumps(self, obj):
+        options = {'cls': self.encoder} if self.encoder else {}
+        return json.dumps(obj, **options)
+
+
+class JSONField(CheckFieldDefaultMixin, Field):
+    empty_strings_allowed = False
+    description = _('A JSON object')
+    default_error_messages = {
+        'invalid': _("Value must be valid JSON."),
+    }
+    _default_hint = ('dict', '{}')
+
+    def __init__(self, verbose_name=None, name=None, encoder=None, **kwargs):
+        if encoder and not callable(encoder):
+            raise ValueError("The encoder parameter must be a callable object.")
+        self.encoder = encoder
+        super().__init__(verbose_name, name, **kwargs)
+
+    def db_type(self, connection):
+        return 'jsonb'
+
+    def deconstruct(self):
+        name, path, args, kwargs = super().deconstruct()
+        if self.encoder is not None:
+            kwargs['encoder'] = self.encoder
+        return name, path, args, kwargs
+
+    def get_transform(self, name):
+        transform = super().get_transform(name)
+        if transform:
+            return transform
+        return KeyTransformFactory(name)
+
+    def get_prep_value(self, value):
+        if value is not None:
+            return JsonAdapter(value, encoder=self.encoder)
+        return value
+
+    def validate(self, value, model_instance):
+        super().validate(value, model_instance)
+        options = {'cls': self.encoder} if self.encoder else {}
+        try:
+            json.dumps(value, **options)
+        except TypeError:
+            raise exceptions.ValidationError(
+                self.error_messages['invalid'],
+                code='invalid',
+                params={'value': value},
+            )
+
+    def value_to_string(self, obj):
+        return self.value_from_object(obj)
+
+    def formfield(self, **kwargs):
+        return super().formfield(**{
+            'form_class': forms.JSONField,
+            **kwargs,
+        })
+
+
+JSONField.register_lookup(lookups.DataContains)
+JSONField.register_lookup(lookups.ContainedBy)
+JSONField.register_lookup(lookups.HasKey)
+JSONField.register_lookup(lookups.HasKeys)
+JSONField.register_lookup(lookups.HasAnyKeys)
+JSONField.register_lookup(lookups.JSONExact)
+
+
+class KeyTransform(Transform):
+    operator = '->'
+    nested_operator = '#>'
+
+    def __init__(self, key_name, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.key_name = key_name
+
+    def as_sql(self, compiler, connection):
+        key_transforms = [self.key_name]
+        previous = self.lhs
+        while isinstance(previous, KeyTransform):
+            key_transforms.insert(0, previous.key_name)
+            previous = previous.lhs
+        lhs, params = compiler.compile(previous)
+        if len(key_transforms) > 1:
+            return "(%s %s %%s)" % (lhs, self.nested_operator), [key_transforms] + params
+        try:
+            lookup = int(self.key_name)
+        except ValueError:
+            lookup = self.key_name
+        return '(%s %s %%s)' % (lhs, self.operator), tuple(params) + (lookup,)
+
+
+class KeyTextTransform(KeyTransform):
+    operator = '->>'
+    nested_operator = '#>>'
+    output_field = TextField()
+
+
+class KeyTransformTextLookupMixin:
+    """
+    Mixin for combining with a lookup expecting a text lhs from a JSONField
+    key lookup. Make use of the ->> operator instead of casting key values to
+    text and performing the lookup on the resulting representation.
+    """
+    def __init__(self, key_transform, *args, **kwargs):
+        assert isinstance(key_transform, KeyTransform)
+        key_text_transform = KeyTextTransform(
+            key_transform.key_name, *key_transform.source_expressions, **key_transform.extra
+        )
+        super().__init__(key_text_transform, *args, **kwargs)
+
+
+class KeyTransformIExact(KeyTransformTextLookupMixin, builtin_lookups.IExact):
+    pass
+
+
+class KeyTransformIContains(KeyTransformTextLookupMixin, builtin_lookups.IContains):
+    pass
+
+
+class KeyTransformStartsWith(KeyTransformTextLookupMixin, builtin_lookups.StartsWith):
+    pass
+
+
+class KeyTransformIStartsWith(KeyTransformTextLookupMixin, builtin_lookups.IStartsWith):
+    pass
+
+
+class KeyTransformEndsWith(KeyTransformTextLookupMixin, builtin_lookups.EndsWith):
+    pass
+
+
+class KeyTransformIEndsWith(KeyTransformTextLookupMixin, builtin_lookups.IEndsWith):
+    pass
+
+
+class KeyTransformRegex(KeyTransformTextLookupMixin, builtin_lookups.Regex):
+    pass
+
+
+class KeyTransformIRegex(KeyTransformTextLookupMixin, builtin_lookups.IRegex):
+    pass
+
+
+KeyTransform.register_lookup(KeyTransformIExact)
+KeyTransform.register_lookup(KeyTransformIContains)
+KeyTransform.register_lookup(KeyTransformStartsWith)
+KeyTransform.register_lookup(KeyTransformIStartsWith)
+KeyTransform.register_lookup(KeyTransformEndsWith)
+KeyTransform.register_lookup(KeyTransformIEndsWith)
+KeyTransform.register_lookup(KeyTransformRegex)
+KeyTransform.register_lookup(KeyTransformIRegex)
+
+
+class KeyTransformFactory:
+
+    def __init__(self, key_name):
+        self.key_name = key_name
+
+    def __call__(self, *args, **kwargs):
+        return KeyTransform(self.key_name, *args, **kwargs)

venv/lib/python3.7/site-packages/django/contrib/postgres/fields/mixins.py

@@ -0,0 +1,29 @@
+from django.core import checks
+
+
+class CheckFieldDefaultMixin:
+    _default_hint = ('<valid default>', '<invalid default>')
+
+    def _check_default(self):
+        if self.has_default() and self.default is not None and not callable(self.default):
+            return [
+                checks.Warning(
+                    "%s default should be a callable instead of an instance so "
+                    "that it's not shared between all field instances." % (
+                        self.__class__.__name__,
+                    ),
+                    hint=(
+                        'Use a callable instead, e.g., use `%s` instead of '
+                        '`%s`.' % self._default_hint
+                    ),
+                    obj=self,
+                    id='postgres.E003',
+                )
+            ]
+        else:
+            return []
+
+    def check(self, **kwargs):
+        errors = super().check(**kwargs)
+        errors.extend(self._check_default())
+        return errors

venv/lib/python3.7/site-packages/django/contrib/postgres/fields/ranges.py

@@ -0,0 +1,274 @@
+import datetime
+import json
+
+from psycopg2.extras import DateRange, DateTimeTZRange, NumericRange, Range
+
+from django.contrib.postgres import forms, lookups
+from django.db import models
+
+from .utils import AttributeSetter
+
+__all__ = [
+    'RangeField', 'IntegerRangeField', 'BigIntegerRangeField',
+    'DecimalRangeField', 'DateTimeRangeField', 'DateRangeField',
+    'FloatRangeField',
+]
+
+
+class RangeField(models.Field):
+    empty_strings_allowed = False
+
+    def __init__(self, *args, **kwargs):
+        # Initializing base_field here ensures that its model matches the model for self.
+        if hasattr(self, 'base_field'):
+            self.base_field = self.base_field()
+        super().__init__(*args, **kwargs)
+
+    @property
+    def model(self):
+        try:
+            return self.__dict__['model']
+        except KeyError:
+            raise AttributeError("'%s' object has no attribute 'model'" % self.__class__.__name__)
+
+    @model.setter
+    def model(self, model):
+        self.__dict__['model'] = model
+        self.base_field.model = model
+
+    def get_prep_value(self, value):
+        if value is None:
+            return None
+        elif isinstance(value, Range):
+            return value
+        elif isinstance(value, (list, tuple)):
+            return self.range_type(value[0], value[1])
+        return value
+
+    def to_python(self, value):
+        if isinstance(value, str):
+            # Assume we're deserializing
+            vals = json.loads(value)
+            for end in ('lower', 'upper'):
+                if end in vals:
+                    vals[end] = self.base_field.to_python(vals[end])
+            value = self.range_type(**vals)
+        elif isinstance(value, (list, tuple)):
+            value = self.range_type(value[0], value[1])
+        return value
+
+    def set_attributes_from_name(self, name):
+        super().set_attributes_from_name(name)
+        self.base_field.set_attributes_from_name(name)
+
+    def value_to_string(self, obj):
+        value = self.value_from_object(obj)
+        if value is None:
+            return None
+        if value.isempty:
+            return json.dumps({"empty": True})
+        base_field = self.base_field
+        result = {"bounds": value._bounds}
+        for end in ('lower', 'upper'):
+            val = getattr(value, end)
+            if val is None:
+                result[end] = None
+            else:
+                obj = AttributeSetter(base_field.attname, val)
+                result[end] = base_field.value_to_string(obj)
+        return json.dumps(result)
+
+    def formfield(self, **kwargs):
+        kwargs.setdefault('form_class', self.form_field)
+        return super().formfield(**kwargs)
+
+
+class IntegerRangeField(RangeField):
+    base_field = models.IntegerField
+    range_type = NumericRange
+    form_field = forms.IntegerRangeField
+
+    def db_type(self, connection):
+        return 'int4range'
+
+
+class BigIntegerRangeField(RangeField):
+    base_field = models.BigIntegerField
+    range_type = NumericRange
+    form_field = forms.IntegerRangeField
+
+    def db_type(self, connection):
+        return 'int8range'
+
+
+class DecimalRangeField(RangeField):
+    base_field = models.DecimalField
+    range_type = NumericRange
+    form_field = forms.DecimalRangeField
+
+    def db_type(self, connection):
+        return 'numrange'
+
+
+class FloatRangeField(RangeField):
+    system_check_deprecated_details = {
+        'msg': (
+            'FloatRangeField is deprecated and will be removed in Django 3.1.'
+        ),
+        'hint': 'Use DecimalRangeField instead.',
+        'id': 'fields.W902',
+    }
+    base_field = models.FloatField
+    range_type = NumericRange
+    form_field = forms.FloatRangeField
+
+    def db_type(self, connection):
+        return 'numrange'
+
+
+class DateTimeRangeField(RangeField):
+    base_field = models.DateTimeField
+    range_type = DateTimeTZRange
+    form_field = forms.DateTimeRangeField
+
+    def db_type(self, connection):
+        return 'tstzrange'
+
+
+class DateRangeField(RangeField):
+    base_field = models.DateField
+    range_type = DateRange
+    form_field = forms.DateRangeField
+
+    def db_type(self, connection):
+        return 'daterange'
+
+
+RangeField.register_lookup(lookups.DataContains)
+RangeField.register_lookup(lookups.ContainedBy)
+RangeField.register_lookup(lookups.Overlap)
+
+
+class DateTimeRangeContains(models.Lookup):
+    """
+    Lookup for Date/DateTimeRange containment to cast the rhs to the correct
+    type.
+    """
+    lookup_name = 'contains'
+
+    def process_rhs(self, compiler, connection):
+        # Transform rhs value for db lookup.
+        if isinstance(self.rhs, datetime.date):
+            output_field = models.DateTimeField() if isinstance(self.rhs, datetime.datetime) else models.DateField()
+            value = models.Value(self.rhs, output_field=output_field)
+            self.rhs = value.resolve_expression(compiler.query)
+        return super().process_rhs(compiler, connection)
+
+    def as_sql(self, compiler, connection):
+        lhs, lhs_params = self.process_lhs(compiler, connection)
+        rhs, rhs_params = self.process_rhs(compiler, connection)
+        params = lhs_params + rhs_params
+        # Cast the rhs if needed.
+        cast_sql = ''
+        if (
+            isinstance(self.rhs, models.Expression) and
+            self.rhs._output_field_or_none and
+            # Skip cast if rhs has a matching range type.
+            not isinstance(self.rhs._output_field_or_none, self.lhs.output_field.__class__)
+        ):
+            cast_internal_type = self.lhs.output_field.base_field.get_internal_type()
+            cast_sql = '::{}'.format(connection.data_types.get(cast_internal_type))
+        return '%s @> %s%s' % (lhs, rhs, cast_sql), params
+
+
+DateRangeField.register_lookup(DateTimeRangeContains)
+DateTimeRangeField.register_lookup(DateTimeRangeContains)
+
+
+class RangeContainedBy(models.Lookup):
+    lookup_name = 'contained_by'
+    type_mapping = {
+        'integer': 'int4range',
+        'bigint': 'int8range',
+        'double precision': 'numrange',
+        'date': 'daterange',
+        'timestamp with time zone': 'tstzrange',
+    }
+
+    def as_sql(self, qn, connection):
+        field = self.lhs.output_field
+        if isinstance(field, models.FloatField):
+            sql = '%s::numeric <@ %s::{}'.format(self.type_mapping[field.db_type(connection)])
+        else:
+            sql = '%s <@ %s::{}'.format(self.type_mapping[field.db_type(connection)])
+        lhs, lhs_params = self.process_lhs(qn, connection)
+        rhs, rhs_params = self.process_rhs(qn, connection)
+        params = lhs_params + rhs_params
+        return sql % (lhs, rhs), params
+
+    def get_prep_lookup(self):
+        return RangeField().get_prep_value(self.rhs)
+
+
+models.DateField.register_lookup(RangeContainedBy)
+models.DateTimeField.register_lookup(RangeContainedBy)
+models.IntegerField.register_lookup(RangeContainedBy)
+models.BigIntegerField.register_lookup(RangeContainedBy)
+models.FloatField.register_lookup(RangeContainedBy)
+
+
+@RangeField.register_lookup
+class FullyLessThan(lookups.PostgresSimpleLookup):
+    lookup_name = 'fully_lt'
+    operator = '<<'
+
+
+@RangeField.register_lookup
+class FullGreaterThan(lookups.PostgresSimpleLookup):
+    lookup_name = 'fully_gt'
+    operator = '>>'
+
+
+@RangeField.register_lookup
+class NotLessThan(lookups.PostgresSimpleLookup):
+    lookup_name = 'not_lt'
+    operator = '&>'
+
+
+@RangeField.register_lookup
+class NotGreaterThan(lookups.PostgresSimpleLookup):
+    lookup_name = 'not_gt'
+    operator = '&<'
+
+
+@RangeField.register_lookup
+class AdjacentToLookup(lookups.PostgresSimpleLookup):
+    lookup_name = 'adjacent_to'
+    operator = '-|-'
+
+
+@RangeField.register_lookup
+class RangeStartsWith(models.Transform):
+    lookup_name = 'startswith'
+    function = 'lower'
+
+    @property
+    def output_field(self):
+        return self.lhs.output_field.base_field
+
+
+@RangeField.register_lookup
+class RangeEndsWith(models.Transform):
+    lookup_name = 'endswith'
+    function = 'upper'
+
+    @property
+    def output_field(self):
+        return self.lhs.output_field.base_field
+
+
+@RangeField.register_lookup
+class IsEmpty(models.Transform):
+    lookup_name = 'isempty'
+    function = 'isempty'
+    output_field = models.BooleanField()

venv/lib/python3.7/site-packages/django/contrib/postgres/fields/utils.py

@@ -0,0 +1,3 @@
+class AttributeSetter:
+    def __init__(self, name, value):
+        setattr(self, name, value)