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sqlglot.helper

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  1from __future__ import annotations
  2
  3import inspect
  4import logging
  5import re
  6import sys
  7import typing as t
  8from collections.abc import Collection
  9from contextlib import contextmanager
 10from copy import copy
 11from enum import Enum
 12
 13if t.TYPE_CHECKING:
 14    from sqlglot import exp
 15    from sqlglot.expressions import Expression
 16
 17    T = t.TypeVar("T")
 18    E = t.TypeVar("E", bound=Expression)
 19
 20CAMEL_CASE_PATTERN = re.compile("(?<!^)(?=[A-Z])")
 21PYTHON_VERSION = sys.version_info[:2]
 22logger = logging.getLogger("sqlglot")
 23
 24
 25class AutoName(Enum):
 26    """This is used for creating enum classes where `auto()` is the string form of the corresponding value's name."""
 27
 28    def _generate_next_value_(name, _start, _count, _last_values):  # type: ignore
 29        return name
 30
 31
 32def seq_get(seq: t.Sequence[T], index: int) -> t.Optional[T]:
 33    """Returns the value in `seq` at position `index`, or `None` if `index` is out of bounds."""
 34    try:
 35        return seq[index]
 36    except IndexError:
 37        return None
 38
 39
 40@t.overload
 41def ensure_list(value: t.Collection[T]) -> t.List[T]:
 42    ...
 43
 44
 45@t.overload
 46def ensure_list(value: T) -> t.List[T]:
 47    ...
 48
 49
 50def ensure_list(value):
 51    """
 52    Ensures that a value is a list, otherwise casts or wraps it into one.
 53
 54    Args:
 55        value: the value of interest.
 56
 57    Returns:
 58        The value cast as a list if it's a list or a tuple, or else the value wrapped in a list.
 59    """
 60    if value is None:
 61        return []
 62    if isinstance(value, (list, tuple)):
 63        return list(value)
 64
 65    return [value]
 66
 67
 68@t.overload
 69def ensure_collection(value: t.Collection[T]) -> t.Collection[T]:
 70    ...
 71
 72
 73@t.overload
 74def ensure_collection(value: T) -> t.Collection[T]:
 75    ...
 76
 77
 78def ensure_collection(value):
 79    """
 80    Ensures that a value is a collection (excluding `str` and `bytes`), otherwise wraps it into a list.
 81
 82    Args:
 83        value: the value of interest.
 84
 85    Returns:
 86        The value if it's a collection, or else the value wrapped in a list.
 87    """
 88    if value is None:
 89        return []
 90    return (
 91        value if isinstance(value, Collection) and not isinstance(value, (str, bytes)) else [value]
 92    )
 93
 94
 95def csv(*args, sep: str = ", ") -> str:
 96    """
 97    Formats any number of string arguments as CSV.
 98
 99    Args:
100        args: the string arguments to format.
101        sep: the argument separator.
102
103    Returns:
104        The arguments formatted as a CSV string.
105    """
106    return sep.join(arg for arg in args if arg)
107
108
109def subclasses(
110    module_name: str,
111    classes: t.Type | t.Tuple[t.Type, ...],
112    exclude: t.Type | t.Tuple[t.Type, ...] = (),
113) -> t.List[t.Type]:
114    """
115    Returns all subclasses for a collection of classes, possibly excluding some of them.
116
117    Args:
118        module_name: the name of the module to search for subclasses in.
119        classes: class(es) we want to find the subclasses of.
120        exclude: class(es) we want to exclude from the returned list.
121
122    Returns:
123        The target subclasses.
124    """
125    return [
126        obj
127        for _, obj in inspect.getmembers(
128            sys.modules[module_name],
129            lambda obj: inspect.isclass(obj) and issubclass(obj, classes) and obj not in exclude,
130        )
131    ]
132
133
134def apply_index_offset(
135    this: exp.Expression,
136    expressions: t.List[t.Optional[E]],
137    offset: int,
138) -> t.List[t.Optional[E]]:
139    """
140    Applies an offset to a given integer literal expression.
141
142    Args:
143        this: the target of the index
144        expressions: the expression the offset will be applied to, wrapped in a list.
145        offset: the offset that will be applied.
146
147    Returns:
148        The original expression with the offset applied to it, wrapped in a list. If the provided
149        `expressions` argument contains more than one expressions, it's returned unaffected.
150    """
151    if not offset or len(expressions) != 1:
152        return expressions
153
154    expression = expressions[0]
155
156    from sqlglot import exp
157    from sqlglot.optimizer.annotate_types import annotate_types
158    from sqlglot.optimizer.simplify import simplify
159
160    if not this.type:
161        annotate_types(this)
162
163    if t.cast(exp.DataType, this.type).this not in (
164        exp.DataType.Type.UNKNOWN,
165        exp.DataType.Type.ARRAY,
166    ):
167        return expressions
168
169    if expression:
170        if not expression.type:
171            annotate_types(expression)
172        if t.cast(exp.DataType, expression.type).this in exp.DataType.INTEGER_TYPES:
173            logger.warning("Applying array index offset (%s)", offset)
174            expression = simplify(
175                exp.Add(this=expression.copy(), expression=exp.Literal.number(offset))
176            )
177            return [expression]
178
179    return expressions
180
181
182def camel_to_snake_case(name: str) -> str:
183    """Converts `name` from camelCase to snake_case and returns the result."""
184    return CAMEL_CASE_PATTERN.sub("_", name).upper()
185
186
187def while_changing(expression: Expression, func: t.Callable[[Expression], E]) -> E:
188    """
189    Applies a transformation to a given expression until a fix point is reached.
190
191    Args:
192        expression: the expression to be transformed.
193        func: the transformation to be applied.
194
195    Returns:
196        The transformed expression.
197    """
198    while True:
199        for n, *_ in reversed(tuple(expression.walk())):
200            n._hash = hash(n)
201        start = hash(expression)
202        expression = func(expression)
203
204        for n, *_ in expression.walk():
205            n._hash = None
206        if start == hash(expression):
207            break
208    return expression
209
210
211def tsort(dag: t.Dict[T, t.List[T]]) -> t.List[T]:
212    """
213    Sorts a given directed acyclic graph in topological order.
214
215    Args:
216        dag: the graph to be sorted.
217
218    Returns:
219        A list that contains all of the graph's nodes in topological order.
220    """
221    result = []
222
223    def visit(node: T, visited: t.Set[T]) -> None:
224        if node in result:
225            return
226        if node in visited:
227            raise ValueError("Cycle error")
228
229        visited.add(node)
230
231        for dep in dag.get(node, []):
232            visit(dep, visited)
233
234        visited.remove(node)
235        result.append(node)
236
237    for node in dag:
238        visit(node, set())
239
240    return result
241
242
243def open_file(file_name: str) -> t.TextIO:
244    """Open a file that may be compressed as gzip and return it in universal newline mode."""
245    with open(file_name, "rb") as f:
246        gzipped = f.read(2) == b"\x1f\x8b"
247
248    if gzipped:
249        import gzip
250
251        return gzip.open(file_name, "rt", newline="")
252
253    return open(file_name, encoding="utf-8", newline="")
254
255
256@contextmanager
257def csv_reader(read_csv: exp.ReadCSV) -> t.Any:
258    """
259    Returns a csv reader given the expression `READ_CSV(name, ['delimiter', '|', ...])`.
260
261    Args:
262        read_csv: a `ReadCSV` function call
263
264    Yields:
265        A python csv reader.
266    """
267    args = read_csv.expressions
268    file = open_file(read_csv.name)
269
270    delimiter = ","
271    args = iter(arg.name for arg in args)
272    for k, v in zip(args, args):
273        if k == "delimiter":
274            delimiter = v
275
276    try:
277        import csv as csv_
278
279        yield csv_.reader(file, delimiter=delimiter)
280    finally:
281        file.close()
282
283
284def find_new_name(taken: t.Collection[str], base: str) -> str:
285    """
286    Searches for a new name.
287
288    Args:
289        taken: a collection of taken names.
290        base: base name to alter.
291
292    Returns:
293        The new, available name.
294    """
295    if base not in taken:
296        return base
297
298    i = 2
299    new = f"{base}_{i}"
300    while new in taken:
301        i += 1
302        new = f"{base}_{i}"
303
304    return new
305
306
307def object_to_dict(obj: t.Any, **kwargs) -> t.Dict:
308    """Returns a dictionary created from an object's attributes."""
309    return {**{k: copy(v) for k, v in vars(obj).copy().items()}, **kwargs}
310
311
312def split_num_words(
313    value: str, sep: str, min_num_words: int, fill_from_start: bool = True
314) -> t.List[t.Optional[str]]:
315    """
316    Perform a split on a value and return N words as a result with `None` used for words that don't exist.
317
318    Args:
319        value: the value to be split.
320        sep: the value to use to split on.
321        min_num_words: the minimum number of words that are going to be in the result.
322        fill_from_start: indicates that if `None` values should be inserted at the start or end of the list.
323
324    Examples:
325        >>> split_num_words("db.table", ".", 3)
326        [None, 'db', 'table']
327        >>> split_num_words("db.table", ".", 3, fill_from_start=False)
328        ['db', 'table', None]
329        >>> split_num_words("db.table", ".", 1)
330        ['db', 'table']
331
332    Returns:
333        The list of words returned by `split`, possibly augmented by a number of `None` values.
334    """
335    words = value.split(sep)
336    if fill_from_start:
337        return [None] * (min_num_words - len(words)) + words
338    return words + [None] * (min_num_words - len(words))
339
340
341def is_iterable(value: t.Any) -> bool:
342    """
343    Checks if the value is an iterable, excluding the types `str` and `bytes`.
344
345    Examples:
346        >>> is_iterable([1,2])
347        True
348        >>> is_iterable("test")
349        False
350
351    Args:
352        value: the value to check if it is an iterable.
353
354    Returns:
355        A `bool` value indicating if it is an iterable.
356    """
357    return hasattr(value, "__iter__") and not isinstance(value, (str, bytes))
358
359
360def flatten(values: t.Iterable[t.Iterable[t.Any] | t.Any]) -> t.Iterator[t.Any]:
361    """
362    Flattens an iterable that can contain both iterable and non-iterable elements. Objects of
363    type `str` and `bytes` are not regarded as iterables.
364
365    Examples:
366        >>> list(flatten([[1, 2], 3, {4}, (5, "bla")]))
367        [1, 2, 3, 4, 5, 'bla']
368        >>> list(flatten([1, 2, 3]))
369        [1, 2, 3]
370
371    Args:
372        values: the value to be flattened.
373
374    Yields:
375        Non-iterable elements in `values`.
376    """
377    for value in values:
378        if is_iterable(value):
379            yield from flatten(value)
380        else:
381            yield value
382
383
384def count_params(function: t.Callable) -> int:
385    """
386    Returns the number of formal parameters expected by a function, without counting "self"
387    and "cls", in case of instance and class methods, respectively.
388    """
389    count = function.__code__.co_argcount
390    return count - 1 if inspect.ismethod(function) else count
391
392
393def dict_depth(d: t.Dict) -> int:
394    """
395    Get the nesting depth of a dictionary.
396
397    For example:
398        >>> dict_depth(None)
399        0
400        >>> dict_depth({})
401        1
402        >>> dict_depth({"a": "b"})
403        1
404        >>> dict_depth({"a": {}})
405        2
406        >>> dict_depth({"a": {"b": {}}})
407        3
408
409    Args:
410        d (dict): dictionary
411
412    Returns:
413        int: depth
414    """
415    try:
416        return 1 + dict_depth(next(iter(d.values())))
417    except AttributeError:
418        # d doesn't have attribute "values"
419        return 0
420    except StopIteration:
421        # d.values() returns an empty sequence
422        return 1
423
424
425def first(it: t.Iterable[T]) -> T:
426    """Returns the first element from an iterable.
427
428    Useful for sets.
429    """
430    return next(i for i in it)
431
432
433def should_identify(text: str, identify: str | bool) -> bool:
434    """Checks if text should be identified given an identify option.
435
436    Args:
437        text: the text to check.
438        identify: "always" | True - always returns true, "safe" - true if no upper case
439
440    Returns:
441        Whether or not a string should be identified.
442    """
443    if identify is True or identify == "always":
444        return True
445    if identify == "safe":
446        return not any(char.isupper() for char in text)
447    return False

class AutoName(enum.Enum): View Source

26class AutoName(Enum):
27    """This is used for creating enum classes where `auto()` is the string form of the corresponding value's name."""
28
29    def _generate_next_value_(name, _start, _count, _last_values):  # type: ignore
30        return name

This is used for creating enum classes where auto() is the string form of the corresponding value's name.

Inherited Members

enum.Enum: name; value

def seq_get(seq: Sequence[~T], index: int) -> Optional[~T]: View Source

33def seq_get(seq: t.Sequence[T], index: int) -> t.Optional[T]:
34    """Returns the value in `seq` at position `index`, or `None` if `index` is out of bounds."""
35    try:
36        return seq[index]
37    except IndexError:
38        return None

Returns the value in seq at position index, or None if index is out of bounds.

def ensure_list(value): View Source

51def ensure_list(value):
52    """
53    Ensures that a value is a list, otherwise casts or wraps it into one.
54
55    Args:
56        value: the value of interest.
57
58    Returns:
59        The value cast as a list if it's a list or a tuple, or else the value wrapped in a list.
60    """
61    if value is None:
62        return []
63    if isinstance(value, (list, tuple)):
64        return list(value)
65
66    return [value]

Ensures that a value is a list, otherwise casts or wraps it into one.

Arguments:

value: the value of interest.

Returns:

The value cast as a list if it's a list or a tuple, or else the value wrapped in a list.

def ensure_collection(value): View Source

79def ensure_collection(value):
80    """
81    Ensures that a value is a collection (excluding `str` and `bytes`), otherwise wraps it into a list.
82
83    Args:
84        value: the value of interest.
85
86    Returns:
87        The value if it's a collection, or else the value wrapped in a list.
88    """
89    if value is None:
90        return []
91    return (
92        value if isinstance(value, Collection) and not isinstance(value, (str, bytes)) else [value]
93    )

Ensures that a value is a collection (excluding str and bytes), otherwise wraps it into a list.

Arguments:

value: the value of interest.

Returns:

The value if it's a collection, or else the value wrapped in a list.

def csv(*args, sep: str = ', ') -> str: View Source

 96def csv(*args, sep: str = ", ") -> str:
 97    """
 98    Formats any number of string arguments as CSV.
 99
100    Args:
101        args: the string arguments to format.
102        sep: the argument separator.
103
104    Returns:
105        The arguments formatted as a CSV string.
106    """
107    return sep.join(arg for arg in args if arg)

Formats any number of string arguments as CSV.

Arguments:

args: the string arguments to format.
sep: the argument separator.

Returns:

The arguments formatted as a CSV string.

def subclasses( module_name: str, classes: Union[Type, Tuple[Type, ...]], exclude: Union[Type, Tuple[Type, ...]] = ()) -> List[Type]: View Source

110def subclasses(
111    module_name: str,
112    classes: t.Type | t.Tuple[t.Type, ...],
113    exclude: t.Type | t.Tuple[t.Type, ...] = (),
114) -> t.List[t.Type]:
115    """
116    Returns all subclasses for a collection of classes, possibly excluding some of them.
117
118    Args:
119        module_name: the name of the module to search for subclasses in.
120        classes: class(es) we want to find the subclasses of.
121        exclude: class(es) we want to exclude from the returned list.
122
123    Returns:
124        The target subclasses.
125    """
126    return [
127        obj
128        for _, obj in inspect.getmembers(
129            sys.modules[module_name],
130            lambda obj: inspect.isclass(obj) and issubclass(obj, classes) and obj not in exclude,
131        )
132    ]

Returns all subclasses for a collection of classes, possibly excluding some of them.

Arguments:

module_name: the name of the module to search for subclasses in.
classes: class(es) we want to find the subclasses of.
exclude: class(es) we want to exclude from the returned list.

Returns:

The target subclasses.

def apply_index_offset( this: sqlglot.expressions.Expression, expressions: List[Optional[~E]], offset: int) -> List[Optional[~E]]: View Source

135def apply_index_offset(
136    this: exp.Expression,
137    expressions: t.List[t.Optional[E]],
138    offset: int,
139) -> t.List[t.Optional[E]]:
140    """
141    Applies an offset to a given integer literal expression.
142
143    Args:
144        this: the target of the index
145        expressions: the expression the offset will be applied to, wrapped in a list.
146        offset: the offset that will be applied.
147
148    Returns:
149        The original expression with the offset applied to it, wrapped in a list. If the provided
150        `expressions` argument contains more than one expressions, it's returned unaffected.
151    """
152    if not offset or len(expressions) != 1:
153        return expressions
154
155    expression = expressions[0]
156
157    from sqlglot import exp
158    from sqlglot.optimizer.annotate_types import annotate_types
159    from sqlglot.optimizer.simplify import simplify
160
161    if not this.type:
162        annotate_types(this)
163
164    if t.cast(exp.DataType, this.type).this not in (
165        exp.DataType.Type.UNKNOWN,
166        exp.DataType.Type.ARRAY,
167    ):
168        return expressions
169
170    if expression:
171        if not expression.type:
172            annotate_types(expression)
173        if t.cast(exp.DataType, expression.type).this in exp.DataType.INTEGER_TYPES:
174            logger.warning("Applying array index offset (%s)", offset)
175            expression = simplify(
176                exp.Add(this=expression.copy(), expression=exp.Literal.number(offset))
177            )
178            return [expression]
179
180    return expressions

Applies an offset to a given integer literal expression.

Arguments:

this: the target of the index
expressions: the expression the offset will be applied to, wrapped in a list.
offset: the offset that will be applied.

Returns:

The original expression with the offset applied to it, wrapped in a list. If the provided expressions argument contains more than one expressions, it's returned unaffected.

def camel_to_snake_case(name: str) -> str: View Source

183def camel_to_snake_case(name: str) -> str:
184    """Converts `name` from camelCase to snake_case and returns the result."""
185    return CAMEL_CASE_PATTERN.sub("_", name).upper()

Converts name from camelCase to snake_case and returns the result.

def while_changing( expression: sqlglot.expressions.Expression, func: Callable[[sqlglot.expressions.Expression], ~E]) -> ~E: View Source

188def while_changing(expression: Expression, func: t.Callable[[Expression], E]) -> E:
189    """
190    Applies a transformation to a given expression until a fix point is reached.
191
192    Args:
193        expression: the expression to be transformed.
194        func: the transformation to be applied.
195
196    Returns:
197        The transformed expression.
198    """
199    while True:
200        for n, *_ in reversed(tuple(expression.walk())):
201            n._hash = hash(n)
202        start = hash(expression)
203        expression = func(expression)
204
205        for n, *_ in expression.walk():
206            n._hash = None
207        if start == hash(expression):
208            break
209    return expression

Applies a transformation to a given expression until a fix point is reached.

Arguments:

expression: the expression to be transformed.
func: the transformation to be applied.

Returns:

The transformed expression.

def tsort(dag: Dict[~T, List[~T]]) -> List[~T]: View Source

212def tsort(dag: t.Dict[T, t.List[T]]) -> t.List[T]:
213    """
214    Sorts a given directed acyclic graph in topological order.
215
216    Args:
217        dag: the graph to be sorted.
218
219    Returns:
220        A list that contains all of the graph's nodes in topological order.
221    """
222    result = []
223
224    def visit(node: T, visited: t.Set[T]) -> None:
225        if node in result:
226            return
227        if node in visited:
228            raise ValueError("Cycle error")
229
230        visited.add(node)
231
232        for dep in dag.get(node, []):
233            visit(dep, visited)
234
235        visited.remove(node)
236        result.append(node)
237
238    for node in dag:
239        visit(node, set())
240
241    return result

Sorts a given directed acyclic graph in topological order.

Arguments:

dag: the graph to be sorted.

Returns:

A list that contains all of the graph's nodes in topological order.

def open_file(file_name: str) -> <class 'TextIO'>: View Source

244def open_file(file_name: str) -> t.TextIO:
245    """Open a file that may be compressed as gzip and return it in universal newline mode."""
246    with open(file_name, "rb") as f:
247        gzipped = f.read(2) == b"\x1f\x8b"
248
249    if gzipped:
250        import gzip
251
252        return gzip.open(file_name, "rt", newline="")
253
254    return open(file_name, encoding="utf-8", newline="")

Open a file that may be compressed as gzip and return it in universal newline mode.

@contextmanager

def csv_reader(read_csv: sqlglot.expressions.ReadCSV) -> Any: View Source

257@contextmanager
258def csv_reader(read_csv: exp.ReadCSV) -> t.Any:
259    """
260    Returns a csv reader given the expression `READ_CSV(name, ['delimiter', '|', ...])`.
261
262    Args:
263        read_csv: a `ReadCSV` function call
264
265    Yields:
266        A python csv reader.
267    """
268    args = read_csv.expressions
269    file = open_file(read_csv.name)
270
271    delimiter = ","
272    args = iter(arg.name for arg in args)
273    for k, v in zip(args, args):
274        if k == "delimiter":
275            delimiter = v
276
277    try:
278        import csv as csv_
279
280        yield csv_.reader(file, delimiter=delimiter)
281    finally:
282        file.close()

Returns a csv reader given the expression READ_CSV(name, ['delimiter', '|', ...]).

Arguments:

read_csv: a ReadCSV function call

Yields:

A python csv reader.

def find_new_name(taken: Collection[str], base: str) -> str: View Source

285def find_new_name(taken: t.Collection[str], base: str) -> str:
286    """
287    Searches for a new name.
288
289    Args:
290        taken: a collection of taken names.
291        base: base name to alter.
292
293    Returns:
294        The new, available name.
295    """
296    if base not in taken:
297        return base
298
299    i = 2
300    new = f"{base}_{i}"
301    while new in taken:
302        i += 1
303        new = f"{base}_{i}"
304
305    return new

Searches for a new name.

Arguments:

taken: a collection of taken names.
base: base name to alter.

Returns:

The new, available name.

def object_to_dict(obj: Any, **kwargs) -> Dict: View Source

308def object_to_dict(obj: t.Any, **kwargs) -> t.Dict:
309    """Returns a dictionary created from an object's attributes."""
310    return {**{k: copy(v) for k, v in vars(obj).copy().items()}, **kwargs}

Returns a dictionary created from an object's attributes.

def split_num_words( value: str, sep: str, min_num_words: int, fill_from_start: bool = True) -> List[Optional[str]]: View Source

313def split_num_words(
314    value: str, sep: str, min_num_words: int, fill_from_start: bool = True
315) -> t.List[t.Optional[str]]:
316    """
317    Perform a split on a value and return N words as a result with `None` used for words that don't exist.
318
319    Args:
320        value: the value to be split.
321        sep: the value to use to split on.
322        min_num_words: the minimum number of words that are going to be in the result.
323        fill_from_start: indicates that if `None` values should be inserted at the start or end of the list.
324
325    Examples:
326        >>> split_num_words("db.table", ".", 3)
327        [None, 'db', 'table']
328        >>> split_num_words("db.table", ".", 3, fill_from_start=False)
329        ['db', 'table', None]
330        >>> split_num_words("db.table", ".", 1)
331        ['db', 'table']
332
333    Returns:
334        The list of words returned by `split`, possibly augmented by a number of `None` values.
335    """
336    words = value.split(sep)
337    if fill_from_start:
338        return [None] * (min_num_words - len(words)) + words
339    return words + [None] * (min_num_words - len(words))

Perform a split on a value and return N words as a result with None used for words that don't exist.

Arguments:

value: the value to be split.
sep: the value to use to split on.
min_num_words: the minimum number of words that are going to be in the result.
fill_from_start: indicates that if None values should be inserted at the start or end of the list.

Examples:

>>> split_num_words("db.table", ".", 3)
[None, 'db', 'table']
>>> split_num_words("db.table", ".", 3, fill_from_start=False)
['db', 'table', None]
>>> split_num_words("db.table", ".", 1)
['db', 'table']

Returns:

The list of words returned by split, possibly augmented by a number of None values.

def is_iterable(value: Any) -> bool: View Source

342def is_iterable(value: t.Any) -> bool:
343    """
344    Checks if the value is an iterable, excluding the types `str` and `bytes`.
345
346    Examples:
347        >>> is_iterable([1,2])
348        True
349        >>> is_iterable("test")
350        False
351
352    Args:
353        value: the value to check if it is an iterable.
354
355    Returns:
356        A `bool` value indicating if it is an iterable.
357    """
358    return hasattr(value, "__iter__") and not isinstance(value, (str, bytes))

Checks if the value is an iterable, excluding the types str and bytes.

Examples:

>>> is_iterable([1,2])
True
>>> is_iterable("test")
False

Arguments:

value: the value to check if it is an iterable.

Returns:

A bool value indicating if it is an iterable.

def flatten(values: Iterable[Union[Iterable[Any], Any]]) -> Iterator[Any]: View Source

361def flatten(values: t.Iterable[t.Iterable[t.Any] | t.Any]) -> t.Iterator[t.Any]:
362    """
363    Flattens an iterable that can contain both iterable and non-iterable elements. Objects of
364    type `str` and `bytes` are not regarded as iterables.
365
366    Examples:
367        >>> list(flatten([[1, 2], 3, {4}, (5, "bla")]))
368        [1, 2, 3, 4, 5, 'bla']
369        >>> list(flatten([1, 2, 3]))
370        [1, 2, 3]
371
372    Args:
373        values: the value to be flattened.
374
375    Yields:
376        Non-iterable elements in `values`.
377    """
378    for value in values:
379        if is_iterable(value):
380            yield from flatten(value)
381        else:
382            yield value

Flattens an iterable that can contain both iterable and non-iterable elements. Objects of type str and bytes are not regarded as iterables.

Examples:

>>> list(flatten([[1, 2], 3, {4}, (5, "bla")]))
[1, 2, 3, 4, 5, 'bla']
>>> list(flatten([1, 2, 3]))
[1, 2, 3]

Arguments:

values: the value to be flattened.

Yields:

Non-iterable elements in values.

def count_params(function: Callable) -> int: View Source

385def count_params(function: t.Callable) -> int:
386    """
387    Returns the number of formal parameters expected by a function, without counting "self"
388    and "cls", in case of instance and class methods, respectively.
389    """
390    count = function.__code__.co_argcount
391    return count - 1 if inspect.ismethod(function) else count

Returns the number of formal parameters expected by a function, without counting "self" and "cls", in case of instance and class methods, respectively.

def dict_depth(d: Dict) -> int: View Source

394def dict_depth(d: t.Dict) -> int:
395    """
396    Get the nesting depth of a dictionary.
397
398    For example:
399        >>> dict_depth(None)
400        0
401        >>> dict_depth({})
402        1
403        >>> dict_depth({"a": "b"})
404        1
405        >>> dict_depth({"a": {}})
406        2
407        >>> dict_depth({"a": {"b": {}}})
408        3
409
410    Args:
411        d (dict): dictionary
412
413    Returns:
414        int: depth
415    """
416    try:
417        return 1 + dict_depth(next(iter(d.values())))
418    except AttributeError:
419        # d doesn't have attribute "values"
420        return 0
421    except StopIteration:
422        # d.values() returns an empty sequence
423        return 1

Get the nesting depth of a dictionary.

For example:

>>> dict_depth(None)
0
>>> dict_depth({})
1
>>> dict_depth({"a": "b"})
1
>>> dict_depth({"a": {}})
2
>>> dict_depth({"a": {"b": {}}})
3

Arguments:

d (dict): dictionary

Returns:

int: depth

def first(it: Iterable[~T]) -> ~T: View Source

426def first(it: t.Iterable[T]) -> T:
427    """Returns the first element from an iterable.
428
429    Useful for sets.
430    """
431    return next(i for i in it)

Returns the first element from an iterable.

Useful for sets.

def should_identify(text: str, identify: str | bool) -> bool: View Source

434def should_identify(text: str, identify: str | bool) -> bool:
435    """Checks if text should be identified given an identify option.
436
437    Args:
438        text: the text to check.
439        identify: "always" | True - always returns true, "safe" - true if no upper case
440
441    Returns:
442        Whether or not a string should be identified.
443    """
444    if identify is True or identify == "always":
445        return True
446    if identify == "safe":
447        return not any(char.isupper() for char in text)
448    return False

Checks if text should be identified given an identify option.

Arguments:

text: the text to check.
identify: "always" | True - always returns true, "safe" - true if no upper case

Returns:

Whether or not a string should be identified.