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IMPROVEMENT: Minor redis improvements (#13381)

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- **Description:**
- Fixes a `key_prefix` bug where passing it in on
`Redis.from_existing(...)` did not work properly. Updates doc strings
accordingly.
- Updates Redis filter classes logic with best practices on typing,
string formatting, and handling "empty" filters.
- Fixes a bug that would prevent multiple tag filters from being applied
together in some scenarios.
- Added a whole new filter unit testing module. Also updated code
formatting for a number of modules that were failing the `make`
commands.
  - **Issue:** N/A
  - **Dependencies:** N/A
  - **Tag maintainer:** @baskaryan 
  - **Twitter handle:** @tchutch94
This commit is contained in:
Tyler Hutcherson 2023-11-19 22:15:45 -05:00 committed by GitHub
parent 674bd90a47
commit 190952fe76
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GPG Key ID: 4AEE18F83AFDEB23
4 changed files with 342 additions and 97 deletions
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8
libs/langchain/langchain/utilities/redis.py
View File

@ -28,7 +28,7 @@ class TokenEscaper:
# Characters that RediSearch requires us to escape during queries.
# Source: https://redis.io/docs/stack/search/reference/escaping/#the-rules-of-text-field-tokenization
DEFAULT_ESCAPED_CHARS = r"[,.<>{}\[\]\\\"\':;!@#$%^&*()\-+=~\/]"
DEFAULT_ESCAPED_CHARS = r"[,.<>{}\[\]\\\"\':;!@#$%^&*()\-+=~\/ ]"
def __init__(self, escape_chars_re: Optional[Pattern] = None):
if escape_chars_re:
@ -37,6 +37,12 @@ class TokenEscaper:
self.escaped_chars_re = re.compile(self.DEFAULT_ESCAPED_CHARS)
def escape(self, value: str) -> str:
if not isinstance(value, str):
raise TypeError(
"Value must be a string object for token escaping."
f"Got type {type(value)}"
)
def escape_symbol(match: re.Match) -> str:
value = match.group(0)
return f"\\{value}"

52
libs/langchain/langchain/vectorstores/redis/base.py
View File

@ -60,9 +60,9 @@ def check_index_exists(client: RedisType, index_name: str) -> bool:
try:
client.ft(index_name).info()
except: # noqa: E722
logger.info("Index does not exist")
logger.debug("Index does not exist")
return False
logger.info("Index already exists")
logger.debug("Index already exists")
return True
@ -155,9 +155,12 @@ class Redis(VectorStore):
.. code-block:: python
rds = Redis.from_existing_index(
# must pass in schema and key_prefix from another index
existing_rds = Redis.from_existing_index(
embeddings, # an Embeddings object
index_name="my-index",
schema=rds.schema, # schema dumped from another index
key_prefix=rds.key_prefix, # key prefix from another index
redis_url="redis://localhost:6379",
)
@ -249,7 +252,7 @@ class Redis(VectorStore):
key_prefix: Optional[str] = None,
**kwargs: Any,
):
"""Initialize with necessary components."""
"""Initialize Redis vector store with necessary components."""
self._check_deprecated_kwargs(kwargs)
try:
# TODO use importlib to check if redis is installed
@ -401,6 +404,7 @@ class Redis(VectorStore):
index_schema = generated_schema
# Create instance
# init the class -- if Redis is unavailable, will throw exception
instance = cls(
redis_url,
index_name,
@ -495,6 +499,7 @@ class Redis(VectorStore):
embedding: Embeddings,
index_name: str,
schema: Union[Dict[str, str], str, os.PathLike],
key_prefix: Optional[str] = None,
**kwargs: Any,
) -> Redis:
"""Connect to an existing Redis index.
@ -504,11 +509,16 @@ class Redis(VectorStore):
from langchain.vectorstores import Redis
from langchain.embeddings import OpenAIEmbeddings
embeddings = OpenAIEmbeddings()
redisearch = Redis.from_existing_index(
# must pass in schema and key_prefix from another index
existing_rds = Redis.from_existing_index(
embeddings,
index_name="my-index",
redis_url="redis://username:password@localhost:6379"
schema=rds.schema, # schema dumped from another index
key_prefix=rds.key_prefix, # key prefix from another index
redis_url="redis://username:password@localhost:6379",
)
Args:
@ -516,8 +526,9 @@ class Redis(VectorStore):
for embedding queries.
index_name (str): Name of the index to connect to.
schema (Union[Dict[str, str], str, os.PathLike]): Schema of the index
and the vector schema. Can be a dict, or path to yaml file
and the vector schema. Can be a dict, or path to yaml file.
key_prefix (Optional[str]): Prefix to use for all keys in Redis associated
with this index.
**kwargs (Any): Additional keyword arguments to pass to the Redis client.
Returns:
@ -528,29 +539,32 @@ class Redis(VectorStore):
ImportError: If the redis python package is not installed.
"""
redis_url = get_from_dict_or_env(kwargs, "redis_url", "REDIS_URL")
try:
# We need to first remove redis_url from kwargs,
# otherwise passing it to Redis will result in an error.
if "redis_url" in kwargs:
kwargs.pop("redis_url")
client = get_client(redis_url=redis_url, **kwargs)
# check if redis has redisearch module installed
check_redis_module_exist(client, REDIS_REQUIRED_MODULES)
# ensure that the index already exists
assert check_index_exists(
client, index_name
), f"Index {index_name} does not exist"
except Exception as e:
raise ValueError(f"Redis failed to connect: {e}")
return cls(
# Create instance
# init the class -- if Redis is unavailable, will throw exception
instance = cls(
redis_url,
index_name,
embedding,
index_schema=schema,
key_prefix=key_prefix,
**kwargs,
)
# Check for existence of the declared index
if not check_index_exists(instance.client, index_name):
# Will only raise if the running Redis server does not
# have a record of this particular index
raise ValueError(
f"Redis failed to connect: Index {index_name} does not exist."
)
return instance
@property
def schema(self) -> Dict[str, List[Any]]:
"""Return the schema of the index."""

178
libs/langchain/langchain/vectorstores/redis/filters.py
View File

@ -1,7 +1,6 @@
from enum import Enum
from functools import wraps
from numbers import Number
from typing import Any, Callable, Dict, List, Optional, Union
from typing import Any, Callable, Dict, List, Optional, Set, Tuple, Union
from langchain.utilities.redis import TokenEscaper
@ -57,7 +56,7 @@ class RedisFilterField:
return self._field == other._field and self._value == other._value
def _set_value(
self, val: Any, val_type: type, operator: RedisFilterOperator
self, val: Any, val_type: Tuple[Any], operator: RedisFilterOperator
) -> None:
# check that the operator is supported by this class
if operator not in self.OPERATORS:
@ -108,15 +107,15 @@ class RedisTag(RedisFilterField):
RedisFilterOperator.NE: "!=",
RedisFilterOperator.IN: "==",
}
OPERATOR_MAP: Dict[RedisFilterOperator, str] = {
RedisFilterOperator.EQ: "@%s:{%s}",
RedisFilterOperator.NE: "(-@%s:{%s})",
RedisFilterOperator.IN: "@%s:{%s}",
}
SUPPORTED_VAL_TYPES = (list, set, tuple, str, type(None))
def __init__(self, field: str):
"""Create a RedisTag FilterField
"""Create a RedisTag FilterField.
Args:
field (str): The name of the RedisTag field in the index to be queried
@ -125,21 +124,33 @@ class RedisTag(RedisFilterField):
super().__init__(field)
def _set_tag_value(
self, other: Union[List[str], str], operator: RedisFilterOperator
self,
other: Union[List[str], Set[str], Tuple[str], str],
operator: RedisFilterOperator,
) -> None:
if isinstance(other, list):
if not all(isinstance(tag, str) for tag in other):
raise ValueError("All tags must be strings")
else:
if isinstance(other, (list, set, tuple)):
try:
# "if val" clause removes non-truthy values from list
other = [str(val) for val in other if val]
except ValueError:
raise ValueError("All tags within collection must be strings")
# above to catch the "" case
elif not other:
other = []
elif isinstance(other, str):
other = [other]
self._set_value(other, list, operator)
self._set_value(other, self.SUPPORTED_VAL_TYPES, operator) # type: ignore
@check_operator_misuse
def __eq__(self, other: Union[List[str], str]) -> "RedisFilterExpression":
"""Create a RedisTag equality filter expression
def __eq__(
self, other: Union[List[str], Set[str], Tuple[str], str]
) -> "RedisFilterExpression":
"""Create a RedisTag equality filter expression.
Args:
other (Union[List[str], str]): The tag(s) to filter on.
other (Union[List[str], Set[str], Tuple[str], str]):
The tag(s) to filter on.
Example:
>>> from langchain.vectorstores.redis import RedisTag
@ -149,11 +160,14 @@ class RedisTag(RedisFilterField):
return RedisFilterExpression(str(self))
@check_operator_misuse
def __ne__(self, other: Union[List[str], str]) -> "RedisFilterExpression":
"""Create a RedisTag inequality filter expression
def __ne__(
self, other: Union[List[str], Set[str], Tuple[str], str]
) -> "RedisFilterExpression":
"""Create a RedisTag inequality filter expression.
Args:
other (Union[List[str], str]): The tag(s) to filter on.
other (Union[List[str], Set[str], Tuple[str], str]):
The tag(s) to filter on.
Example:
>>> from langchain.vectorstores.redis import RedisTag
@ -167,12 +181,10 @@ class RedisTag(RedisFilterField):
return "|".join([self.escaper.escape(tag) for tag in self._value])
def __str__(self) -> str:
"""Return the query syntax for a RedisTag filter expression."""
if not self._value:
raise ValueError(
f"Operator must be used before calling __str__. Operators are "
f"{self.OPERATORS.values()}"
)
"""Return the Redis Query syntax for a RedisTag filter expression"""
return "*"
return self.OPERATOR_MAP[self._operator] % (
self._field,
self._formatted_tag_value,
@ -191,21 +203,19 @@ class RedisNum(RedisFilterField):
RedisFilterOperator.GE: ">=",
}
OPERATOR_MAP: Dict[RedisFilterOperator, str] = {
RedisFilterOperator.EQ: "@%s:[%f %f]",
RedisFilterOperator.NE: "(-@%s:[%f %f])",
RedisFilterOperator.GT: "@%s:[(%f +inf]",
RedisFilterOperator.LT: "@%s:[-inf (%f]",
RedisFilterOperator.GE: "@%s:[%f +inf]",
RedisFilterOperator.LE: "@%s:[-inf %f]",
RedisFilterOperator.EQ: "@%s:[%s %s]",
RedisFilterOperator.NE: "(-@%s:[%s %s])",
RedisFilterOperator.GT: "@%s:[(%s +inf]",
RedisFilterOperator.LT: "@%s:[-inf (%s]",
RedisFilterOperator.GE: "@%s:[%s +inf]",
RedisFilterOperator.LE: "@%s:[-inf %s]",
}
SUPPORTED_VAL_TYPES = (int, float, type(None))
def __str__(self) -> str:
"""Return the Redis Query syntax for a Numeric filter expression"""
"""Return the query syntax for a RedisNum filter expression."""
if not self._value:
raise ValueError(
f"Operator must be used before calling __str__. Operators are "
f"{self.OPERATORS.values()}"
)
return "*"
if (
self._operator == RedisFilterOperator.EQ
@ -221,102 +231,103 @@ class RedisNum(RedisFilterField):
@check_operator_misuse
def __eq__(self, other: Union[int, float]) -> "RedisFilterExpression":
"""Create a Numeric equality filter expression
"""Create a Numeric equality filter expression.
Args:
other (Number): The value to filter on.
other (Union[int, float]): The value to filter on.
Example:
>>> from langchain.vectorstores.redis import RedisNum
>>> filter = RedisNum("zipcode") == 90210
"""
self._set_value(other, Number, RedisFilterOperator.EQ)
self._set_value(other, self.SUPPORTED_VAL_TYPES, RedisFilterOperator.EQ) # type: ignore
return RedisFilterExpression(str(self))
@check_operator_misuse
def __ne__(self, other: Union[int, float]) -> "RedisFilterExpression":
"""Create a Numeric inequality filter expression
"""Create a Numeric inequality filter expression.
Args:
other (Number): The value to filter on.
other (Union[int, float]): The value to filter on.
Example:
>>> from langchain.vectorstores.redis import RedisNum
>>> filter = RedisNum("zipcode") != 90210
"""
self._set_value(other, Number, RedisFilterOperator.NE)
self._set_value(other, self.SUPPORTED_VAL_TYPES, RedisFilterOperator.NE) # type: ignore
return RedisFilterExpression(str(self))
def __gt__(self, other: Union[int, float]) -> "RedisFilterExpression":
"""Create a RedisNumeric greater than filter expression
"""Create a Numeric greater than filter expression.
Args:
other (Number): The value to filter on.
other (Union[int, float]): The value to filter on.
Example:
>>> from langchain.vectorstores.redis import RedisNum
>>> filter = RedisNum("age") > 18
"""
self._set_value(other, Number, RedisFilterOperator.GT)
self._set_value(other, self.SUPPORTED_VAL_TYPES, RedisFilterOperator.GT) # type: ignore
return RedisFilterExpression(str(self))
def __lt__(self, other: Union[int, float]) -> "RedisFilterExpression":
"""Create a Numeric less than filter expression
"""Create a Numeric less than filter expression.
Args:
other (Number): The value to filter on.
other (Union[int, float]): The value to filter on.
Example:
>>> from langchain.vectorstores.redis import RedisNum
>>> filter = RedisNum("age") < 18
"""
self._set_value(other, Number, RedisFilterOperator.LT)
self._set_value(other, self.SUPPORTED_VAL_TYPES, RedisFilterOperator.LT) # type: ignore
return RedisFilterExpression(str(self))
def __ge__(self, other: Union[int, float]) -> "RedisFilterExpression":
"""Create a Numeric greater than or equal to filter expression
"""Create a Numeric greater than or equal to filter expression.
Args:
other (Number): The value to filter on.
other (Union[int, float]): The value to filter on.
Example:
>>> from langchain.vectorstores.redis import RedisNum
>>> filter = RedisNum("age") >= 18
"""
self._set_value(other, Number, RedisFilterOperator.GE)
self._set_value(other, self.SUPPORTED_VAL_TYPES, RedisFilterOperator.GE) # type: ignore
return RedisFilterExpression(str(self))
def __le__(self, other: Union[int, float]) -> "RedisFilterExpression":
"""Create a Numeric less than or equal to filter expression
"""Create a Numeric less than or equal to filter expression.
Args:
other (Number): The value to filter on.
other (Union[int, float]): The value to filter on.
Example:
>>> from langchain.vectorstores.redis import RedisNum
>>> filter = RedisNum("age") <= 18
"""
self._set_value(other, Number, RedisFilterOperator.LE)
self._set_value(other, self.SUPPORTED_VAL_TYPES, RedisFilterOperator.LE) # type: ignore
return RedisFilterExpression(str(self))
class RedisText(RedisFilterField):
"""A RedisFilterField representing a text field in a Redis index."""
OPERATORS = {
OPERATORS: Dict[RedisFilterOperator, str] = {
RedisFilterOperator.EQ: "==",
RedisFilterOperator.NE: "!=",
RedisFilterOperator.LIKE: "%",
}
OPERATOR_MAP = {
RedisFilterOperator.EQ: '@%s:"%s"',
OPERATOR_MAP: Dict[RedisFilterOperator, str] = {
RedisFilterOperator.EQ: '@%s:("%s")',
RedisFilterOperator.NE: '(-@%s:"%s")',
RedisFilterOperator.LIKE: "@%s:%s",
RedisFilterOperator.LIKE: "@%s:(%s)",
}
SUPPORTED_VAL_TYPES = (str, type(None))
@check_operator_misuse
def __eq__(self, other: str) -> "RedisFilterExpression":
"""Create a RedisText equality filter expression
"""Create a RedisText equality (exact match) filter expression.
Args:
other (str): The text value to filter on.
@ -325,12 +336,12 @@ class RedisText(RedisFilterField):
>>> from langchain.vectorstores.redis import RedisText
>>> filter = RedisText("job") == "engineer"
"""
self._set_value(other, str, RedisFilterOperator.EQ)
self._set_value(other, self.SUPPORTED_VAL_TYPES, RedisFilterOperator.EQ) # type: ignore
return RedisFilterExpression(str(self))
@check_operator_misuse
def __ne__(self, other: str) -> "RedisFilterExpression":
"""Create a RedisText inequality filter expression
"""Create a RedisText inequality filter expression.
Args:
other (str): The text value to filter on.
@ -339,33 +350,34 @@ class RedisText(RedisFilterField):
>>> from langchain.vectorstores.redis import RedisText
>>> filter = RedisText("job") != "engineer"
"""
self._set_value(other, str, RedisFilterOperator.NE)
self._set_value(other, self.SUPPORTED_VAL_TYPES, RedisFilterOperator.NE) # type: ignore
return RedisFilterExpression(str(self))
def __mod__(self, other: str) -> "RedisFilterExpression":
"""Create a RedisText like filter expression
"""Create a RedisText "LIKE" filter expression.
Args:
other (str): The text value to filter on.
Example:
>>> from langchain.vectorstores.redis import RedisText
>>> filter = RedisText("job") % "engineer"
>>> filter = RedisText("job") % "engine*" # suffix wild card match
>>> filter = RedisText("job") % "%%engine%%" # fuzzy match w/ LD
>>> filter = RedisText("job") % "engineer|doctor" # contains either term
>>> filter = RedisText("job") % "engineer doctor" # contains both terms
"""
self._set_value(other, str, RedisFilterOperator.LIKE)
self._set_value(other, self.SUPPORTED_VAL_TYPES, RedisFilterOperator.LIKE) # type: ignore
return RedisFilterExpression(str(self))
def __str__(self) -> str:
"""Return the query syntax for a RedisText filter expression."""
if not self._value:
raise ValueError(
f"Operator must be used before calling __str__. Operators are "
f"{self.OPERATORS.values()}"
)
return "*"
try:
return self.OPERATOR_MAP[self._operator] % (self._field, self._value)
except KeyError:
raise Exception("Invalid operator")
return self.OPERATOR_MAP[self._operator] % (
self._field,
self._value,
)
class RedisFilterExpression:
@ -413,16 +425,36 @@ class RedisFilterExpression:
operator=RedisFilterOperator.OR, left=self, right=other
)
@staticmethod
def format_expression(
left: "RedisFilterExpression", right: "RedisFilterExpression", operator_str: str
) -> str:
_left, _right = str(left), str(right)
if _left == _right == "*":
return _left
if _left == "*" != _right:
return _right
if _right == "*" != _left:
return _left
return f"({_left}{operator_str}{_right})"
def __str__(self) -> str:
# top level check that allows recursive calls to __str__
if not self._filter and not self._operator:
raise ValueError("Improperly initialized RedisFilterExpression")
# allow for single filter expression without operators as last
# expression in the chain might not have an operator
# if there's an operator, combine expressions accordingly
if self._operator:
if not isinstance(self._left, RedisFilterExpression) or not isinstance(
self._right, RedisFilterExpression
):
raise TypeError(
"Improper combination of filters."
"Both left and right should be type FilterExpression"
)
operator_str = " | " if self._operator == RedisFilterOperator.OR else " "
return f"({str(self._left)}{operator_str}{str(self._right)})"
return self.format_expression(self._left, self._right, operator_str)
# check that base case, the filter is set
if not self._filter:

193
libs/langchain/tests/unit_tests/vectorstores/redis/test_filters.py Normal file
View File

@ -0,0 +1,193 @@
from typing import Any
import pytest
from langchain.vectorstores.redis import (
RedisNum as Num,
)
from langchain.vectorstores.redis import (
RedisTag as Tag,
)
from langchain.vectorstores.redis import (
RedisText as Text,
)
# Test cases for various tag scenarios
@pytest.mark.parametrize(
"operation,tags,expected",
[
# Testing single tags
("==", "simpletag", "@tag_field:{simpletag}"),
(
"==",
"tag with space",
"@tag_field:{tag\\ with\\ space}",
), # Escaping spaces within quotes
(
"==",
"special$char",
"@tag_field:{special\\$char}",
), # Escaping a special character
("!=", "negated", "(-@tag_field:{negated})"),
# Testing multiple tags
("==", ["tag1", "tag2"], "@tag_field:{tag1|tag2}"),
(
"==",
["alpha", "beta with space", "gamma$special"],
"@tag_field:{alpha|beta\\ with\\ space|gamma\\$special}",
), # Multiple tags with spaces and special chars
("!=", ["tagA", "tagB"], "(-@tag_field:{tagA|tagB})"),
# Complex tag scenarios with special characters
("==", "weird:tag", "@tag_field:{weird\\:tag}"), # Tags with colon
("==", "tag&another", "@tag_field:{tag\\&another}"), # Tags with ampersand
# Escaping various special characters within tags
("==", "tag/with/slashes", "@tag_field:{tag\\/with\\/slashes}"),
(
"==",
["hyphen-tag", "under_score", "dot.tag"],
"@tag_field:{hyphen\\-tag|under_score|dot\\.tag}",
),
# ...additional unique cases as desired...
],
)
def test_tag_filter_varied(operation: str, tags: str, expected: str) -> None:
if operation == "==":
tf = Tag("tag_field") == tags
elif operation == "!=":
tf = Tag("tag_field") != tags
else:
raise ValueError(f"Unsupported operation: {operation}")
# Verify the string representation matches the expected RediSearch query part
assert str(tf) == expected
@pytest.mark.parametrize(
"value, expected",
[
(None, "*"),
([], "*"),
("", "*"),
([None], "*"),
([None, "tag"], "@tag_field:{tag}"),
],
ids=[
"none",
"empty_list",
"empty_string",
"list_with_none",
"list_with_none_and_tag",
],
)
def test_nullable_tags(value: Any, expected: str) -> None:
tag = Tag("tag_field")
assert str(tag == value) == expected
@pytest.mark.parametrize(
"operation, value, expected",
[
("__eq__", 5, "@numeric_field:[5 5]"),
("__ne__", 5, "(-@numeric_field:[5 5])"),
("__gt__", 5, "@numeric_field:[(5 +inf]"),
("__ge__", 5, "@numeric_field:[5 +inf]"),
("__lt__", 5.55, "@numeric_field:[-inf (5.55]"),
("__le__", 5, "@numeric_field:[-inf 5]"),
("__le__", None, "*"),
("__eq__", None, "*"),
("__ne__", None, "*"),
],
ids=["eq", "ne", "gt", "ge", "lt", "le", "le_none", "eq_none", "ne_none"],
)
def test_numeric_filter(operation: str, value: Any, expected: str) -> None:
nf = Num("numeric_field")
assert str(getattr(nf, operation)(value)) == expected
@pytest.mark.parametrize(
"operation, value, expected",
[
("__eq__", "text", '@text_field:("text")'),
("__ne__", "text", '(-@text_field:"text")'),
("__eq__", "", "*"),
("__ne__", "", "*"),
("__eq__", None, "*"),
("__ne__", None, "*"),
("__mod__", "text", "@text_field:(text)"),
("__mod__", "tex*", "@text_field:(tex*)"),
("__mod__", "%text%", "@text_field:(%text%)"),
("__mod__", "", "*"),
("__mod__", None, "*"),
],
ids=[
"eq",
"ne",
"eq-empty",
"ne-empty",
"eq-none",
"ne-none",
"like",
"like_wildcard",
"like_full",
"like_empty",
"like_none",
],
)
def test_text_filter(operation: str, value: Any, expected: str) -> None:
txt_f = getattr(Text("text_field"), operation)(value)
assert str(txt_f) == expected
def test_filters_combination() -> None:
tf1 = Tag("tag_field") == ["tag1", "tag2"]
tf2 = Tag("tag_field") == "tag3"
combined = tf1 & tf2
assert str(combined) == "(@tag_field:{tag1|tag2} @tag_field:{tag3})"
combined = tf1 | tf2
assert str(combined) == "(@tag_field:{tag1|tag2} | @tag_field:{tag3})"
tf1 = Tag("tag_field") == []
assert str(tf1) == "*"
assert str(tf1 & tf2) == str(tf2)
assert str(tf1 | tf2) == str(tf2)
# test combining filters with None values and empty strings
tf1 = Tag("tag_field") == None # noqa: E711
tf2 = Tag("tag_field") == ""
assert str(tf1 & tf2) == "*"
tf1 = Tag("tag_field") == None # noqa: E711
tf2 = Tag("tag_field") == "tag"
assert str(tf1 & tf2) == str(tf2)
tf1 = Tag("tag_field") == None # noqa: E711
tf2 = Tag("tag_field") == ["tag1", "tag2"]
assert str(tf1 & tf2) == str(tf2)
tf1 = Tag("tag_field") == None # noqa: E711
tf2 = Tag("tag_field") != None # noqa: E711
assert str(tf1 & tf2) == "*"
tf1 = Tag("tag_field") == ""
tf2 = Tag("tag_field") == "tag"
tf3 = Tag("tag_field") == ["tag1", "tag2"]
assert str(tf1 & tf2 & tf3) == str(tf2 & tf3)
# test none filters for Tag Num Text
tf1 = Tag("tag_field") == None # noqa: E711
tf2 = Num("num_field") == None # noqa: E711
tf3 = Text("text_field") == None # noqa: E711
assert str(tf1 & tf2 & tf3) == "*"
tf1 = Tag("tag_field") != None # noqa: E711
tf2 = Num("num_field") != None # noqa: E711
tf3 = Text("text_field") != None # noqa: E711
assert str(tf1 & tf2 & tf3) == "*"
# test combinations of real and None filters
tf1 = Tag("tag_field") == "tag"
tf2 = Num("num_field") == None # noqa: E711
tf3 = Text("text_field") == None # noqa: E711
assert str(tf1 & tf2 & tf3) == str(tf1)