From 1ce302064e3559589998d80113bbe6a34ee4e9ae Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 20:01:06 +0100
Subject: [PATCH 01/35] autogenerate type hints using monkeytype

---
 .gitignore                  |   3 +
 pandas/io/formats/format.py | 212 +++++++++++++++++++-----------------
 2 files changed, 117 insertions(+), 98 deletions(-)

diff --git a/.gitignore b/.gitignore
index 56828fa1d9331..e85da9c9b976b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -66,6 +66,9 @@ coverage_html_report
 # hypothesis test database
 .hypothesis/
 __pycache__
+# pytest-monkeytype
+monkeytype.sqlite3
+
 
 # OS generated files #
 ######################
diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 11b69064723c5..7f77400cd2dcf 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -48,6 +48,22 @@
 from pandas.io.common import _expand_user, _stringify_path
 from pandas.io.formats.printing import adjoin, justify, pprint_thing
 
+from io import StringIO, TextIOWrapper
+from _pytest.capture import EncodedFile
+from dateutil.tz.tz import tzutc
+from dateutil.zoneinfo import tzfile
+from numpy import float64, int32, ndarray, str_
+from pandas._libs.tslibs.nattype import NaTType
+from pandas._libs.tslibs.timestamps import Timestamp
+from pandas.core.arrays.datetimes import DatetimeArray
+from pandas.core.arrays.timedeltas import TimedeltaArray
+from pandas.core.frame import DataFrame
+from pandas.core.indexes.base import Index
+from pandas.core.indexes.timedeltas import TimedeltaIndex
+from pandas.core.series import Series
+from pandas.tests.io.test_common import CustomFSPath
+from py._path.local import LocalPath
+from typing import Any, Callable, Dict, List, Optional, Tuple, Type, Union
 if TYPE_CHECKING:
     from pandas import Series, DataFrame, Categorical
 
@@ -137,8 +153,8 @@ def __init__(
         buf: Optional[TextIO] = None,
         length: bool = True,
         na_rep: str = "NaN",
-        footer: bool = True,
-    ):
+        footer: bool = True
+    ) -> None:
         self.categorical = categorical
         self.buf = buf if buf is not None else StringIO("")
         self.na_rep = na_rep
@@ -206,8 +222,8 @@ def __init__(
         float_format: Optional[str] = None,
         dtype: bool = True,
         max_rows: Optional[int] = None,
-        min_rows: Optional[int] = None,
-    ):
+        min_rows: Optional[int] = None
+    ) -> None:
         self.series = series
         self.buf = buf if buf is not None else StringIO()
         self.name = name
@@ -247,7 +263,7 @@ def _chk_truncate(self) -> None:
             else:
                 row_num = max_rows // 2
                 series = concat((series.iloc[:row_num], series.iloc[-row_num:]))
-            self.tr_row_num = row_num  # type: Optional[int]
+            self.tr_row_num: Optional[int] = row_num
         else:
             self.tr_row_num = None
         self.tr_series = series
@@ -351,21 +367,21 @@ def to_string(self) -> str:
 
 
 class TextAdjustment:
-    def __init__(self):
+    def __init__(self) -> None:
         self.encoding = get_option("display.encoding")
 
-    def len(self, text):
+    def len(self, text: Union[str_, str]) -> int:
         return len(text)
 
-    def justify(self, texts, max_len, mode="right"):
+    def justify(self, texts: Any, max_len: int, mode: str = "right") -> List[str]:
         return justify(texts, max_len, mode=mode)
 
-    def adjoin(self, space, *lists, **kwargs):
+    def adjoin(self, space: int, *lists, **kwargs) -> str:
         return adjoin(space, *lists, strlen=self.len, justfunc=self.justify, **kwargs)
 
 
 class EastAsianTextAdjustment(TextAdjustment):
-    def __init__(self):
+    def __init__(self) -> None:
         super().__init__()
         if get_option("display.unicode.ambiguous_as_wide"):
             self.ambiguous_width = 2
@@ -377,7 +393,7 @@ def __init__(self):
         # Ambiguous width can be changed by option
         self._EAW_MAP = {"Na": 1, "N": 1, "W": 2, "F": 2, "H": 1}
 
-    def len(self, text):
+    def len(self, text: str) -> int:
         """
         Calculate display width considering unicode East Asian Width
         """
@@ -388,7 +404,7 @@ def len(self, text):
             self._EAW_MAP.get(east_asian_width(c), self.ambiguous_width) for c in text
         )
 
-    def justify(self, texts, max_len, mode="right"):
+    def justify(self, texts: Union[Tuple[str, str], List[str], Tuple[str, str, str, str, str], Tuple[str, str, str, str]], max_len: int, mode: str = "right") -> List[str]:
         # re-calculate padding space per str considering East Asian Width
         def _get_pad(t):
             return max_len - self.len(t) + len(t)
@@ -401,7 +417,7 @@ def _get_pad(t):
             return [x.rjust(_get_pad(x)) for x in texts]
 
 
-def _get_adjustment():
+def _get_adjustment() -> Union[TextAdjustment, EastAsianTextAdjustment]:
     use_east_asian_width = get_option("display.unicode.east_asian_width")
     if use_east_asian_width:
         return EastAsianTextAdjustment()
@@ -414,12 +430,12 @@ class TableFormatter:
     show_dimensions = None
 
     @property
-    def should_show_dimensions(self):
+    def should_show_dimensions(self) -> Optional[bool]:
         return self.show_dimensions is True or (
             self.show_dimensions == "truncate" and self.is_truncated
         )
 
-    def _get_formatter(self, i):
+    def _get_formatter(self, i: Union[str, int]) -> Optional[Callable]:
         if isinstance(self.formatters, (list, tuple)):
             if is_integer(i):
                 return self.formatters[i]
@@ -446,28 +462,28 @@ class DataFrameFormatter(TableFormatter):
 
     def __init__(
         self,
-        frame,
-        buf=None,
-        columns=None,
-        col_space=None,
-        header=True,
-        index=True,
-        na_rep="NaN",
-        formatters=None,
-        justify=None,
-        float_format=None,
-        sparsify=None,
-        index_names=True,
-        line_width=None,
-        max_rows=None,
-        min_rows=None,
-        max_cols=None,
-        show_dimensions=False,
-        decimal=".",
-        table_id=None,
-        render_links=False,
+        frame: DataFrame,
+        buf: Optional[Union[StringIO, LocalPath, str, CustomFSPath]] = None,
+        columns: Optional[List[str]] = None,
+        col_space: Optional[Union[str, int]] = None,
+        header: Union[bool, List[str]] = True,
+        index: Union[bool, int] = True,
+        na_rep: str = "NaN",
+        formatters: Optional[Union[Tuple[Callable, Callable, Callable], Dict[str, Callable]]] = None,
+        justify: Optional[str] = None,
+        float_format: Optional[Union[str, Type[str]]] = None,
+        sparsify: Optional[bool] = None,
+        index_names: bool = True,
+        line_width: Optional[int] = None,
+        max_rows: Optional[int] = None,
+        min_rows: Optional[int] = None,
+        max_cols: Optional[int] = None,
+        show_dimensions: Union[bool, str] = False,
+        decimal: str = ".",
+        table_id: Optional[str] = None,
+        render_links: bool = False,
         **kwds
-    ):
+    ) -> None:
         self.frame = frame
         if buf is not None:
             self.buf = _expand_user(_stringify_path(buf))
@@ -742,7 +758,7 @@ def to_string(self) -> None:
                 )
             )
 
-    def _join_multiline(self, *strcols):
+    def _join_multiline(self, *strcols) -> str:
         lwidth = self.line_width
         adjoin_width = 1
         strcols = list(strcols)
@@ -779,13 +795,13 @@ def _join_multiline(self, *strcols):
 
     def to_latex(
         self,
-        column_format=None,
-        longtable=False,
-        encoding=None,
-        multicolumn=False,
-        multicolumn_format=None,
-        multirow=False,
-    ):
+        column_format: Optional[str] = None,
+        longtable: bool = False,
+        encoding: Optional[str] = None,
+        multicolumn: bool = False,
+        multicolumn_format: Optional[str] = None,
+        multirow: bool = False
+    ) -> None:
         """
         Render a DataFrame to a LaTeX tabular/longtable environment output.
         """
@@ -831,7 +847,7 @@ def to_html(
         self,
         classes: Optional[Union[str, List, Tuple]] = None,
         notebook: bool = False,
-        border: Optional[int] = None,
+        border: Optional[int] = None
     ) -> None:
         """
         Render a DataFrame to a html table.
@@ -958,7 +974,7 @@ def _get_formatted_index(self, frame: "DataFrame") -> List[str]:
             return adjoined
 
     def _get_column_name_list(self) -> List[str]:
-        names = []  # type: List[str]
+        names: List[str] = []
         columns = self.frame.columns
         if isinstance(columns, ABCMultiIndex):
             names.extend("" if name is None else name for name in columns.names)
@@ -972,16 +988,16 @@ def _get_column_name_list(self) -> List[str]:
 
 
 def format_array(
-    values,
-    formatter,
-    float_format=None,
-    na_rep="NaN",
-    digits=None,
-    space=None,
-    justify="right",
-    decimal=".",
-    leading_space=None,
-):
+    values: Any,
+    formatter: Optional[Union[Callable, Type[str]]],
+    float_format: Optional[Union[Callable, str, Type[str]]] = None,
+    na_rep: str = "NaN",
+    digits: Optional[int] = None,
+    space: Optional[Union[str, int]] = None,
+    justify: str = "right",
+    decimal: str = ".",
+    leading_space: Optional[bool] = None
+) -> List[str]:
     """
     Format an array for printing.
 
@@ -1051,18 +1067,18 @@ def format_array(
 class GenericArrayFormatter:
     def __init__(
         self,
-        values,
-        digits=7,
-        formatter=None,
-        na_rep="NaN",
-        space=12,
-        float_format=None,
-        justify="right",
-        decimal=".",
-        quoting=None,
-        fixed_width=True,
-        leading_space=None,
-    ):
+        values: Any,
+        digits: int = 7,
+        formatter: Optional[Union[Callable, Type[str]]] = None,
+        na_rep: str = "NaN",
+        space: Union[str, int] = 12,
+        float_format: Optional[Union[str, Callable, EngFormatter, Type[str]]] = None,
+        justify: str = "right",
+        decimal: str = ".",
+        quoting: Optional[int] = None,
+        fixed_width: bool = True,
+        leading_space: Optional[bool] = None
+    ) -> None:
         self.values = values
         self.digits = digits
         self.na_rep = na_rep
@@ -1075,11 +1091,11 @@ def __init__(
         self.fixed_width = fixed_width
         self.leading_space = leading_space
 
-    def get_result(self):
+    def get_result(self) -> Union[ndarray, List[str]]:
         fmt_values = self._format_strings()
         return _make_fixed_width(fmt_values, self.justify)
 
-    def _format_strings(self):
+    def _format_strings(self) -> List[str]:
         if self.float_format is None:
             float_format = get_option("display.float_format")
             if float_format is None:
@@ -1149,7 +1165,7 @@ class FloatArrayFormatter(GenericArrayFormatter):
 
     """
 
-    def __init__(self, *args, **kwargs):
+    def __init__(self, *args, **kwargs) -> None:
         GenericArrayFormatter.__init__(self, *args, **kwargs)
 
         # float_format is expected to be a string
@@ -1161,7 +1177,7 @@ def __init__(self, *args, **kwargs):
                 self.formatter = self.float_format
                 self.float_format = None
 
-    def _value_formatter(self, float_format=None, threshold=None):
+    def _value_formatter(self, float_format: Optional[Union[Callable, partial]] = None, threshold: Optional[Union[float, int]] = None) -> Callable:
         """Returns a function to be applied on each value to format it
         """
 
@@ -1207,7 +1223,7 @@ def formatter(value):
 
         return formatter
 
-    def get_result_as_array(self):
+    def get_result_as_array(self) -> Union[ndarray, List[str]]:
         """
         Returns the float values converted into strings using
         the parameters given at initialisation, as a numpy array
@@ -1296,7 +1312,7 @@ def format_values_with(float_format):
 
         return formatted_values
 
-    def _format_strings(self):
+    def _format_strings(self) -> List[str]:
         # shortcut
         if self.formatter is not None:
             return [self.formatter(x) for x in self.values]
@@ -1305,19 +1321,19 @@ def _format_strings(self):
 
 
 class IntArrayFormatter(GenericArrayFormatter):
-    def _format_strings(self):
+    def _format_strings(self) -> List[str]:
         formatter = self.formatter or (lambda x: "{x: d}".format(x=x))
         fmt_values = [formatter(x) for x in self.values]
         return fmt_values
 
 
 class Datetime64Formatter(GenericArrayFormatter):
-    def __init__(self, values, nat_rep="NaT", date_format=None, **kwargs):
+    def __init__(self, values: Union[ndarray, Series, DatetimeIndex, DatetimeArray], nat_rep: str = "NaT", date_format: None = None, **kwargs) -> None:
         super().__init__(values, **kwargs)
         self.nat_rep = nat_rep
         self.date_format = date_format
 
-    def _format_strings(self):
+    def _format_strings(self) -> List[str]:
         """ we by definition have DO NOT have a TZ """
 
         values = self.values
@@ -1337,7 +1353,7 @@ def _format_strings(self):
 
 
 class ExtensionArrayFormatter(GenericArrayFormatter):
-    def _format_strings(self):
+    def _format_strings(self) -> List[str]:
         values = self.values
         if isinstance(values, (ABCIndexClass, ABCSeries)):
             values = values._values
@@ -1363,7 +1379,7 @@ def _format_strings(self):
         return fmt_values
 
 
-def format_percentiles(percentiles):
+def format_percentiles(percentiles: Union[ndarray, List[Union[int, float]], List[float], List[Union[str, float]]]) -> List[str]:
     """
     Outputs rounded and formatted percentiles.
 
@@ -1429,7 +1445,7 @@ def format_percentiles(percentiles):
     return [i + "%" for i in out]
 
 
-def _is_dates_only(values):
+def _is_dates_only(values: Union[ndarray, DatetimeArray, Index, DatetimeIndex]) -> bool:
     # return a boolean if we are only dates (and don't have a timezone)
     assert values.ndim == 1
 
@@ -1448,7 +1464,7 @@ def _is_dates_only(values):
     return False
 
 
-def _format_datetime64(x, tz=None, nat_rep="NaT"):
+def _format_datetime64(x: Union[NaTType, Timestamp], tz: Optional[Union[tzfile, tzutc]] = None, nat_rep: str = "NaT") -> str:
     if x is None or (is_scalar(x) and isna(x)):
         return nat_rep
 
@@ -1461,7 +1477,7 @@ def _format_datetime64(x, tz=None, nat_rep="NaT"):
     return str(x)
 
 
-def _format_datetime64_dateonly(x, nat_rep="NaT", date_format=None):
+def _format_datetime64_dateonly(x: Union[NaTType, Timestamp], nat_rep: str = "NaT", date_format: None = None) -> str:
     if x is None or (is_scalar(x) and isna(x)):
         return nat_rep
 
@@ -1474,7 +1490,7 @@ def _format_datetime64_dateonly(x, nat_rep="NaT", date_format=None):
         return x._date_repr
 
 
-def _get_format_datetime64(is_dates_only, nat_rep="NaT", date_format=None):
+def _get_format_datetime64(is_dates_only: bool, nat_rep: str = "NaT", date_format: None = None) -> Callable:
 
     if is_dates_only:
         return lambda x, tz=None: _format_datetime64_dateonly(
@@ -1484,7 +1500,7 @@ def _get_format_datetime64(is_dates_only, nat_rep="NaT", date_format=None):
         return lambda x, tz=None: _format_datetime64(x, tz=tz, nat_rep=nat_rep)
 
 
-def _get_format_datetime64_from_values(values, date_format):
+def _get_format_datetime64_from_values(values: Union[ndarray, DatetimeArray, DatetimeIndex], date_format: Optional[str]) -> Optional[str]:
     """ given values and a date_format, return a string format """
 
     if isinstance(values, np.ndarray) and values.ndim > 1:
@@ -1499,7 +1515,7 @@ def _get_format_datetime64_from_values(values, date_format):
 
 
 class Datetime64TZFormatter(Datetime64Formatter):
-    def _format_strings(self):
+    def _format_strings(self) -> List[str]:
         """ we by definition have a TZ """
 
         values = self.values.astype(object)
@@ -1513,12 +1529,12 @@ def _format_strings(self):
 
 
 class Timedelta64Formatter(GenericArrayFormatter):
-    def __init__(self, values, nat_rep="NaT", box=False, **kwargs):
+    def __init__(self, values: Union[ndarray, TimedeltaIndex], nat_rep: str = "NaT", box: bool = False, **kwargs) -> None:
         super().__init__(values, **kwargs)
         self.nat_rep = nat_rep
         self.box = box
 
-    def _format_strings(self):
+    def _format_strings(self) -> ndarray:
         formatter = self.formatter or _get_format_timedelta64(
             self.values, nat_rep=self.nat_rep, box=self.box
         )
@@ -1526,7 +1542,7 @@ def _format_strings(self):
         return fmt_values
 
 
-def _get_format_timedelta64(values, nat_rep="NaT", box=False):
+def _get_format_timedelta64(values: Union[ndarray, TimedeltaIndex, TimedeltaArray], nat_rep: str = "NaT", box: bool = False) -> Callable:
     """
     Return a formatter function for a range of timedeltas.
     These will all have the same format argument
@@ -1567,7 +1583,7 @@ def _formatter(x):
     return _formatter
 
 
-def _make_fixed_width(strings, justify="right", minimum=None, adj=None):
+def _make_fixed_width(strings: Union[ndarray, List[str], List[str_]], justify: str = "right", minimum: Optional[int] = None, adj: Optional[Union[TextAdjustment, EastAsianTextAdjustment]] = None) -> Union[ndarray, List[str]]:
 
     if len(strings) == 0 or justify == "all":
         return strings
@@ -1595,7 +1611,7 @@ def just(x):
     return result
 
 
-def _trim_zeros_complex(str_complexes, na_rep="NaN"):
+def _trim_zeros_complex(str_complexes: ndarray, na_rep: str = "NaN") -> List[str]:
     """
     Separates the real and imaginary parts from the complex number, and
     executes the _trim_zeros_float method on each of those.
@@ -1613,7 +1629,7 @@ def separate_and_trim(str_complex, na_rep):
     return ["".join(separate_and_trim(x, na_rep)) for x in str_complexes]
 
 
-def _trim_zeros_float(str_floats, na_rep="NaN"):
+def _trim_zeros_float(str_floats: Union[ndarray, List[str]], na_rep: str = "NaN") -> List[str]:
     """
     Trims zeros, leaving just one before the decimal points if need be.
     """
@@ -1637,7 +1653,7 @@ def _cond(values):
     return [x + "0" if x.endswith(".") and _is_number(x) else x for x in trimmed]
 
 
-def _has_names(index):
+def _has_names(index: Index) -> bool:
     if isinstance(index, ABCMultiIndex):
         return com._any_not_none(*index.names)
     else:
@@ -1672,11 +1688,11 @@ class EngFormatter:
         24: "Y",
     }
 
-    def __init__(self, accuracy=None, use_eng_prefix=False):
+    def __init__(self, accuracy: Optional[int] = None, use_eng_prefix: bool = False) -> None:
         self.accuracy = accuracy
         self.use_eng_prefix = use_eng_prefix
 
-    def __call__(self, num):
+    def __call__(self, num: Union[float64, int, float]) -> str:
         """ Formats a number in engineering notation, appending a letter
         representing the power of 1000 of the original number. Some examples:
 
@@ -1743,7 +1759,7 @@ def __call__(self, num):
         return formatted
 
 
-def set_eng_float_format(accuracy=3, use_eng_prefix=False):
+def set_eng_float_format(accuracy: int = 3, use_eng_prefix: bool = False) -> None:
     """
     Alter default behavior on how float is formatted in DataFrame.
     Format float in engineering format. By accuracy, we mean the number of
@@ -1756,7 +1772,7 @@ def set_eng_float_format(accuracy=3, use_eng_prefix=False):
     set_option("display.column_space", max(12, accuracy + 9))
 
 
-def _binify(cols, line_width):
+def _binify(cols: List[int32], line_width: Union[int32, int]) -> List[int]:
     adjoin_width = 1
     bins = []
     curr_width = 0
@@ -1776,7 +1792,7 @@ def _binify(cols, line_width):
     return bins
 
 
-def get_level_lengths(levels, sentinel=""):
+def get_level_lengths(levels: Any, sentinel: Union[bool, object, str] = "") -> List[Dict[int, int]]:
     """For each index in each level the function returns lengths of indexes.
 
     Parameters
@@ -1816,7 +1832,7 @@ def get_level_lengths(levels, sentinel=""):
     return result
 
 
-def buffer_put_lines(buf, lines):
+def buffer_put_lines(buf: Union[StringIO, TextIOWrapper, EncodedFile], lines: List[str]) -> None:
     """
     Appends lines to a buffer.
 

From cffc9356b5e02f64fcf6afe4b017acf376a696ea Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 20:03:12 +0100
Subject: [PATCH 02/35] isort and black

---
 pandas/io/formats/format.py | 149 ++++++++++++++++++++++++++----------
 1 file changed, 109 insertions(+), 40 deletions(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 7f77400cd2dcf..948d74079d0b3 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -4,18 +4,37 @@
 """
 
 from functools import partial
-from io import StringIO
+from io import StringIO, TextIOWrapper
 from shutil import get_terminal_size
-from typing import TYPE_CHECKING, List, Optional, TextIO, Tuple, Union, cast
+from typing import (
+    TYPE_CHECKING,
+    Any,
+    Callable,
+    Dict,
+    List,
+    Optional,
+    TextIO,
+    Tuple,
+    Type,
+    Union,
+    cast,
+)
 from unicodedata import east_asian_width
 
+from _pytest.capture import EncodedFile
+from dateutil.tz.tz import tzutc
+from dateutil.zoneinfo import tzfile
 import numpy as np
+from numpy import float64, int32, ndarray, str_
+from py._path.local import LocalPath
 
 from pandas._config.config import get_option, set_option
 
 from pandas._libs import lib
 from pandas._libs.tslib import format_array_from_datetime
 from pandas._libs.tslibs import NaT, Timedelta, Timestamp, iNaT
+from pandas._libs.tslibs.nattype import NaTType
+from pandas._libs.tslibs.timestamps import Timestamp
 
 from pandas.core.dtypes.common import (
     is_categorical_dtype,
@@ -40,30 +59,21 @@
 )
 from pandas.core.dtypes.missing import isna, notna
 
+from pandas.core.arrays.datetimes import DatetimeArray
+from pandas.core.arrays.timedeltas import TimedeltaArray
 from pandas.core.base import PandasObject
 import pandas.core.common as com
+from pandas.core.frame import DataFrame
 from pandas.core.index import Index, ensure_index
+from pandas.core.indexes.base import Index
 from pandas.core.indexes.datetimes import DatetimeIndex
+from pandas.core.indexes.timedeltas import TimedeltaIndex
+from pandas.core.series import Series
+from pandas.tests.io.test_common import CustomFSPath
 
 from pandas.io.common import _expand_user, _stringify_path
 from pandas.io.formats.printing import adjoin, justify, pprint_thing
 
-from io import StringIO, TextIOWrapper
-from _pytest.capture import EncodedFile
-from dateutil.tz.tz import tzutc
-from dateutil.zoneinfo import tzfile
-from numpy import float64, int32, ndarray, str_
-from pandas._libs.tslibs.nattype import NaTType
-from pandas._libs.tslibs.timestamps import Timestamp
-from pandas.core.arrays.datetimes import DatetimeArray
-from pandas.core.arrays.timedeltas import TimedeltaArray
-from pandas.core.frame import DataFrame
-from pandas.core.indexes.base import Index
-from pandas.core.indexes.timedeltas import TimedeltaIndex
-from pandas.core.series import Series
-from pandas.tests.io.test_common import CustomFSPath
-from py._path.local import LocalPath
-from typing import Any, Callable, Dict, List, Optional, Tuple, Type, Union
 if TYPE_CHECKING:
     from pandas import Series, DataFrame, Categorical
 
@@ -153,7 +163,7 @@ def __init__(
         buf: Optional[TextIO] = None,
         length: bool = True,
         na_rep: str = "NaN",
-        footer: bool = True
+        footer: bool = True,
     ) -> None:
         self.categorical = categorical
         self.buf = buf if buf is not None else StringIO("")
@@ -222,7 +232,7 @@ def __init__(
         float_format: Optional[str] = None,
         dtype: bool = True,
         max_rows: Optional[int] = None,
-        min_rows: Optional[int] = None
+        min_rows: Optional[int] = None,
     ) -> None:
         self.series = series
         self.buf = buf if buf is not None else StringIO()
@@ -404,7 +414,17 @@ def len(self, text: str) -> int:
             self._EAW_MAP.get(east_asian_width(c), self.ambiguous_width) for c in text
         )
 
-    def justify(self, texts: Union[Tuple[str, str], List[str], Tuple[str, str, str, str, str], Tuple[str, str, str, str]], max_len: int, mode: str = "right") -> List[str]:
+    def justify(
+        self,
+        texts: Union[
+            Tuple[str, str],
+            List[str],
+            Tuple[str, str, str, str, str],
+            Tuple[str, str, str, str],
+        ],
+        max_len: int,
+        mode: str = "right",
+    ) -> List[str]:
         # re-calculate padding space per str considering East Asian Width
         def _get_pad(t):
             return max_len - self.len(t) + len(t)
@@ -469,7 +489,9 @@ def __init__(
         header: Union[bool, List[str]] = True,
         index: Union[bool, int] = True,
         na_rep: str = "NaN",
-        formatters: Optional[Union[Tuple[Callable, Callable, Callable], Dict[str, Callable]]] = None,
+        formatters: Optional[
+            Union[Tuple[Callable, Callable, Callable], Dict[str, Callable]]
+        ] = None,
         justify: Optional[str] = None,
         float_format: Optional[Union[str, Type[str]]] = None,
         sparsify: Optional[bool] = None,
@@ -800,7 +822,7 @@ def to_latex(
         encoding: Optional[str] = None,
         multicolumn: bool = False,
         multicolumn_format: Optional[str] = None,
-        multirow: bool = False
+        multirow: bool = False,
     ) -> None:
         """
         Render a DataFrame to a LaTeX tabular/longtable environment output.
@@ -847,7 +869,7 @@ def to_html(
         self,
         classes: Optional[Union[str, List, Tuple]] = None,
         notebook: bool = False,
-        border: Optional[int] = None
+        border: Optional[int] = None,
     ) -> None:
         """
         Render a DataFrame to a html table.
@@ -996,7 +1018,7 @@ def format_array(
     space: Optional[Union[str, int]] = None,
     justify: str = "right",
     decimal: str = ".",
-    leading_space: Optional[bool] = None
+    leading_space: Optional[bool] = None,
 ) -> List[str]:
     """
     Format an array for printing.
@@ -1077,7 +1099,7 @@ def __init__(
         decimal: str = ".",
         quoting: Optional[int] = None,
         fixed_width: bool = True,
-        leading_space: Optional[bool] = None
+        leading_space: Optional[bool] = None,
     ) -> None:
         self.values = values
         self.digits = digits
@@ -1177,7 +1199,11 @@ def __init__(self, *args, **kwargs) -> None:
                 self.formatter = self.float_format
                 self.float_format = None
 
-    def _value_formatter(self, float_format: Optional[Union[Callable, partial]] = None, threshold: Optional[Union[float, int]] = None) -> Callable:
+    def _value_formatter(
+        self,
+        float_format: Optional[Union[Callable, partial]] = None,
+        threshold: Optional[Union[float, int]] = None,
+    ) -> Callable:
         """Returns a function to be applied on each value to format it
         """
 
@@ -1328,7 +1354,13 @@ def _format_strings(self) -> List[str]:
 
 
 class Datetime64Formatter(GenericArrayFormatter):
-    def __init__(self, values: Union[ndarray, Series, DatetimeIndex, DatetimeArray], nat_rep: str = "NaT", date_format: None = None, **kwargs) -> None:
+    def __init__(
+        self,
+        values: Union[ndarray, Series, DatetimeIndex, DatetimeArray],
+        nat_rep: str = "NaT",
+        date_format: None = None,
+        **kwargs
+    ) -> None:
         super().__init__(values, **kwargs)
         self.nat_rep = nat_rep
         self.date_format = date_format
@@ -1379,7 +1411,11 @@ def _format_strings(self) -> List[str]:
         return fmt_values
 
 
-def format_percentiles(percentiles: Union[ndarray, List[Union[int, float]], List[float], List[Union[str, float]]]) -> List[str]:
+def format_percentiles(
+    percentiles: Union[
+        ndarray, List[Union[int, float]], List[float], List[Union[str, float]]
+    ]
+) -> List[str]:
     """
     Outputs rounded and formatted percentiles.
 
@@ -1464,7 +1500,11 @@ def _is_dates_only(values: Union[ndarray, DatetimeArray, Index, DatetimeIndex])
     return False
 
 
-def _format_datetime64(x: Union[NaTType, Timestamp], tz: Optional[Union[tzfile, tzutc]] = None, nat_rep: str = "NaT") -> str:
+def _format_datetime64(
+    x: Union[NaTType, Timestamp],
+    tz: Optional[Union[tzfile, tzutc]] = None,
+    nat_rep: str = "NaT",
+) -> str:
     if x is None or (is_scalar(x) and isna(x)):
         return nat_rep
 
@@ -1477,7 +1517,9 @@ def _format_datetime64(x: Union[NaTType, Timestamp], tz: Optional[Union[tzfile,
     return str(x)
 
 
-def _format_datetime64_dateonly(x: Union[NaTType, Timestamp], nat_rep: str = "NaT", date_format: None = None) -> str:
+def _format_datetime64_dateonly(
+    x: Union[NaTType, Timestamp], nat_rep: str = "NaT", date_format: None = None
+) -> str:
     if x is None or (is_scalar(x) and isna(x)):
         return nat_rep
 
@@ -1490,7 +1532,9 @@ def _format_datetime64_dateonly(x: Union[NaTType, Timestamp], nat_rep: str = "Na
         return x._date_repr
 
 
-def _get_format_datetime64(is_dates_only: bool, nat_rep: str = "NaT", date_format: None = None) -> Callable:
+def _get_format_datetime64(
+    is_dates_only: bool, nat_rep: str = "NaT", date_format: None = None
+) -> Callable:
 
     if is_dates_only:
         return lambda x, tz=None: _format_datetime64_dateonly(
@@ -1500,7 +1544,9 @@ def _get_format_datetime64(is_dates_only: bool, nat_rep: str = "NaT", date_forma
         return lambda x, tz=None: _format_datetime64(x, tz=tz, nat_rep=nat_rep)
 
 
-def _get_format_datetime64_from_values(values: Union[ndarray, DatetimeArray, DatetimeIndex], date_format: Optional[str]) -> Optional[str]:
+def _get_format_datetime64_from_values(
+    values: Union[ndarray, DatetimeArray, DatetimeIndex], date_format: Optional[str]
+) -> Optional[str]:
     """ given values and a date_format, return a string format """
 
     if isinstance(values, np.ndarray) and values.ndim > 1:
@@ -1529,7 +1575,13 @@ def _format_strings(self) -> List[str]:
 
 
 class Timedelta64Formatter(GenericArrayFormatter):
-    def __init__(self, values: Union[ndarray, TimedeltaIndex], nat_rep: str = "NaT", box: bool = False, **kwargs) -> None:
+    def __init__(
+        self,
+        values: Union[ndarray, TimedeltaIndex],
+        nat_rep: str = "NaT",
+        box: bool = False,
+        **kwargs
+    ) -> None:
         super().__init__(values, **kwargs)
         self.nat_rep = nat_rep
         self.box = box
@@ -1542,7 +1594,11 @@ def _format_strings(self) -> ndarray:
         return fmt_values
 
 
-def _get_format_timedelta64(values: Union[ndarray, TimedeltaIndex, TimedeltaArray], nat_rep: str = "NaT", box: bool = False) -> Callable:
+def _get_format_timedelta64(
+    values: Union[ndarray, TimedeltaIndex, TimedeltaArray],
+    nat_rep: str = "NaT",
+    box: bool = False,
+) -> Callable:
     """
     Return a formatter function for a range of timedeltas.
     These will all have the same format argument
@@ -1583,7 +1639,12 @@ def _formatter(x):
     return _formatter
 
 
-def _make_fixed_width(strings: Union[ndarray, List[str], List[str_]], justify: str = "right", minimum: Optional[int] = None, adj: Optional[Union[TextAdjustment, EastAsianTextAdjustment]] = None) -> Union[ndarray, List[str]]:
+def _make_fixed_width(
+    strings: Union[ndarray, List[str], List[str_]],
+    justify: str = "right",
+    minimum: Optional[int] = None,
+    adj: Optional[Union[TextAdjustment, EastAsianTextAdjustment]] = None,
+) -> Union[ndarray, List[str]]:
 
     if len(strings) == 0 or justify == "all":
         return strings
@@ -1629,7 +1690,9 @@ def separate_and_trim(str_complex, na_rep):
     return ["".join(separate_and_trim(x, na_rep)) for x in str_complexes]
 
 
-def _trim_zeros_float(str_floats: Union[ndarray, List[str]], na_rep: str = "NaN") -> List[str]:
+def _trim_zeros_float(
+    str_floats: Union[ndarray, List[str]], na_rep: str = "NaN"
+) -> List[str]:
     """
     Trims zeros, leaving just one before the decimal points if need be.
     """
@@ -1688,7 +1751,9 @@ class EngFormatter:
         24: "Y",
     }
 
-    def __init__(self, accuracy: Optional[int] = None, use_eng_prefix: bool = False) -> None:
+    def __init__(
+        self, accuracy: Optional[int] = None, use_eng_prefix: bool = False
+    ) -> None:
         self.accuracy = accuracy
         self.use_eng_prefix = use_eng_prefix
 
@@ -1792,7 +1857,9 @@ def _binify(cols: List[int32], line_width: Union[int32, int]) -> List[int]:
     return bins
 
 
-def get_level_lengths(levels: Any, sentinel: Union[bool, object, str] = "") -> List[Dict[int, int]]:
+def get_level_lengths(
+    levels: Any, sentinel: Union[bool, object, str] = ""
+) -> List[Dict[int, int]]:
     """For each index in each level the function returns lengths of indexes.
 
     Parameters
@@ -1832,7 +1899,9 @@ def get_level_lengths(levels: Any, sentinel: Union[bool, object, str] = "") -> L
     return result
 
 
-def buffer_put_lines(buf: Union[StringIO, TextIOWrapper, EncodedFile], lines: List[str]) -> None:
+def buffer_put_lines(
+    buf: Union[StringIO, TextIOWrapper, EncodedFile], lines: List[str]
+) -> None:
     """
     Appends lines to a buffer.
 

From 5c89d1538ecffb15bf36243f0511a9b905262bd0 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 20:13:23 +0100
Subject: [PATCH 03/35] redefinition of unused 'Timestamp' from line
 35flake8(F811)

---
 pandas/io/formats/format.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 948d74079d0b3..a9a4ac4e6a7c9 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -34,7 +34,6 @@
 from pandas._libs.tslib import format_array_from_datetime
 from pandas._libs.tslibs import NaT, Timedelta, Timestamp, iNaT
 from pandas._libs.tslibs.nattype import NaTType
-from pandas._libs.tslibs.timestamps import Timestamp
 
 from pandas.core.dtypes.common import (
     is_categorical_dtype,

From 033846e077f5c9e43d5aa7b548a0335075aa1ada Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 20:14:46 +0100
Subject: [PATCH 04/35] redefinition of unused 'Index' from line 66flake8(F811)

---
 pandas/io/formats/format.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index a9a4ac4e6a7c9..794900a6b104c 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -64,7 +64,6 @@
 import pandas.core.common as com
 from pandas.core.frame import DataFrame
 from pandas.core.index import Index, ensure_index
-from pandas.core.indexes.base import Index
 from pandas.core.indexes.datetimes import DatetimeIndex
 from pandas.core.indexes.timedeltas import TimedeltaIndex
 from pandas.core.series import Series

From 062c0bbcc1fd43f304409652992cf9f440ff52cc Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 20:16:04 +0100
Subject: [PATCH 05/35] undefined name 'EngFormatter'flake8(F821)

---
 pandas/io/formats/format.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 794900a6b104c..031dbd1779835 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -1092,7 +1092,7 @@ def __init__(
         formatter: Optional[Union[Callable, Type[str]]] = None,
         na_rep: str = "NaN",
         space: Union[str, int] = 12,
-        float_format: Optional[Union[str, Callable, EngFormatter, Type[str]]] = None,
+        float_format: Optional[Union[str, Callable, "EngFormatter", Type[str]]] = None,
         justify: str = "right",
         decimal: str = ".",
         quoting: Optional[int] = None,

From 3f4f1ce14ab37cc7e7481b1b5320c78ef056c483 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 20:16:59 +0100
Subject: [PATCH 06/35] redefinition of unused 'Series' from line
 69flake8(F811)

---
 pandas/io/formats/format.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 031dbd1779835..05dfdbe8e0592 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -66,7 +66,6 @@
 from pandas.core.index import Index, ensure_index
 from pandas.core.indexes.datetimes import DatetimeIndex
 from pandas.core.indexes.timedeltas import TimedeltaIndex
-from pandas.core.series import Series
 from pandas.tests.io.test_common import CustomFSPath
 
 from pandas.io.common import _expand_user, _stringify_path

From fc06ebbf1675e995b0248541545afe92fd1040de Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 20:17:20 +0100
Subject: [PATCH 07/35] redefinition of unused 'DataFrame' from line
 65flake8(F811)

---
 pandas/io/formats/format.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 05dfdbe8e0592..3eb2b518fde6a 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -62,7 +62,6 @@
 from pandas.core.arrays.timedeltas import TimedeltaArray
 from pandas.core.base import PandasObject
 import pandas.core.common as com
-from pandas.core.frame import DataFrame
 from pandas.core.index import Index, ensure_index
 from pandas.core.indexes.datetimes import DatetimeIndex
 from pandas.core.indexes.timedeltas import TimedeltaIndex

From 352d57cacad319eb6fd6d9b83d9fb75b2a308ad1 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 20:25:08 +0100
Subject: [PATCH 08/35] ImportError: cannot import name 'Categorical' from
 'pandas'

---
 pandas/io/formats/format.py | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 3eb2b518fde6a..1fd3d253d11f9 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -65,7 +65,6 @@
 from pandas.core.index import Index, ensure_index
 from pandas.core.indexes.datetimes import DatetimeIndex
 from pandas.core.indexes.timedeltas import TimedeltaIndex
-from pandas.tests.io.test_common import CustomFSPath
 
 from pandas.io.common import _expand_user, _stringify_path
 from pandas.io.formats.printing import adjoin, justify, pprint_thing
@@ -479,7 +478,7 @@ class DataFrameFormatter(TableFormatter):
     def __init__(
         self,
         frame: DataFrame,
-        buf: Optional[Union[StringIO, LocalPath, str, CustomFSPath]] = None,
+        buf: Optional[Union[StringIO, LocalPath, str]] = None,
         columns: Optional[List[str]] = None,
         col_space: Optional[Union[str, int]] = None,
         header: Union[bool, List[str]] = True,

From 8b1c63c6061ab2753a1f754965ff2cc3b1115a98 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 20:26:12 +0100
Subject: [PATCH 09/35] NameError: name 'DataFrame' is not defined

---
 pandas/io/formats/format.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 1fd3d253d11f9..fd6e2f048a1f4 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -477,7 +477,7 @@ class DataFrameFormatter(TableFormatter):
 
     def __init__(
         self,
-        frame: DataFrame,
+        frame: "DataFrame",
         buf: Optional[Union[StringIO, LocalPath, str]] = None,
         columns: Optional[List[str]] = None,
         col_space: Optional[Union[str, int]] = None,

From d601eada5759fb162cb2445af439bc57fb85cd12 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 20:27:33 +0100
Subject: [PATCH 10/35] NameError: name 'Series' is not defined

---
 pandas/io/formats/format.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index fd6e2f048a1f4..c4dd0e3612346 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -1351,7 +1351,7 @@ def _format_strings(self) -> List[str]:
 class Datetime64Formatter(GenericArrayFormatter):
     def __init__(
         self,
-        values: Union[ndarray, Series, DatetimeIndex, DatetimeArray],
+        values: Union[ndarray, "Series", DatetimeIndex, DatetimeArray],
         nat_rep: str = "NaT",
         date_format: None = None,
         **kwargs

From 2a97b7606bdabd39f58c72eb684a2b053fa4fceb Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 20:39:34 +0100
Subject: [PATCH 11/35] tests passing locally


From bf8706dcb91f3c415a2be1a8f8b2a9d7bbb7161b Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 20:46:09 +0100
Subject: [PATCH 12/35] undo unwanted changes to py3.5 Syntax for Variable
 Annotations

---
 pandas/io/formats/format.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index c4dd0e3612346..3ca35ac2eec0d 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -268,7 +268,7 @@ def _chk_truncate(self) -> None:
             else:
                 row_num = max_rows // 2
                 series = concat((series.iloc[:row_num], series.iloc[-row_num:]))
-            self.tr_row_num: Optional[int] = row_num
+            self.tr_row_num = row_num  # type: Optional[int]
         else:
             self.tr_row_num = None
         self.tr_series = series
@@ -991,7 +991,7 @@ def _get_formatted_index(self, frame: "DataFrame") -> List[str]:
             return adjoined
 
     def _get_column_name_list(self) -> List[str]:
-        names: List[str] = []
+        names = []  # type: List[str]
         columns = self.frame.columns
         if isinstance(columns, ABCMultiIndex):
             names.extend("" if name is None else name for name in columns.names)

From c02a0fae16eb0b4e068429af70ff5a18425ee782 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 20:52:05 +0100
Subject: [PATCH 13/35] error: "TableFormatter" has no attribute ...

---
 pandas/io/formats/format.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 3ca35ac2eec0d..3d047e31f59b6 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -443,6 +443,9 @@ def _get_adjustment() -> Union[TextAdjustment, EastAsianTextAdjustment]:
 class TableFormatter:
 
     show_dimensions = None
+    is_truncated = None
+    formatters = None
+    columns = None
 
     @property
     def should_show_dimensions(self) -> Optional[bool]:

From 10d0fa3f42b0320b3ffd6e631972ceac7de9c027 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 21:11:06 +0100
Subject: [PATCH 14/35] pandas\io\formats\format.py:463: error: Unsupported
 right operand type for in ("None")

---
 pandas/io/formats/format.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 3d047e31f59b6..ab773632735ce 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -445,7 +445,7 @@ class TableFormatter:
     show_dimensions = None
     is_truncated = None
     formatters = None
-    columns = None
+    columns = None  # type: Index
 
     @property
     def should_show_dimensions(self) -> Optional[bool]:

From 035249dc3d2d62b63d9fce9b5dd7b23fdb201f52 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 21:34:38 +0100
Subject: [PATCH 15/35] pandas\io\formats\format.py:465: error: "None" has no
 attribute "get"

---
 pandas/io/formats/format.py | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index ab773632735ce..d72d7a1cfcd96 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -72,6 +72,10 @@
 if TYPE_CHECKING:
     from pandas import Series, DataFrame, Categorical
 
+formatters_type = Union[
+    List[Callable], Tuple[Callable, ...], Dict[Union[str, int], Callable]
+]
+
 common_docstring = """
         Parameters
         ----------
@@ -87,7 +91,7 @@
             Whether to print index (row) labels.
         na_rep : str, optional, default 'NaN'
             String representation of NAN to use.
-        formatters : list or dict of one-param. functions, optional
+        formatters : list, tuple or dict of one-param. functions, optional
             Formatter functions to apply to columns' elements by position or
             name.
             The result of each function must be a unicode string.
@@ -444,7 +448,7 @@ class TableFormatter:
 
     show_dimensions = None
     is_truncated = None
-    formatters = None
+    formatters = None  # type: formatters_type
     columns = None  # type: Index
 
     @property
@@ -456,6 +460,7 @@ def should_show_dimensions(self) -> Optional[bool]:
     def _get_formatter(self, i: Union[str, int]) -> Optional[Callable]:
         if isinstance(self.formatters, (list, tuple)):
             if is_integer(i):
+                i = cast(int, i)
                 return self.formatters[i]
             else:
                 return None
@@ -487,9 +492,7 @@ def __init__(
         header: Union[bool, List[str]] = True,
         index: Union[bool, int] = True,
         na_rep: str = "NaN",
-        formatters: Optional[
-            Union[Tuple[Callable, Callable, Callable], Dict[str, Callable]]
-        ] = None,
+        formatters: Optional[formatters_type] = None,
         justify: Optional[str] = None,
         float_format: Optional[Union[str, Type[str]]] = None,
         sparsify: Optional[bool] = None,

From fbaa22482c2cf213c2fe5e2d4421cb275ea39c01 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 21:48:45 +0100
Subject: [PATCH 16/35] pandas\io\formats\format.py:534: error: Incompatible
 types in assignment (expression has type "Union[bool, str]", variable has
 type "None")

---
 pandas/io/formats/format.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index d72d7a1cfcd96..cd2d7f3751f76 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -446,7 +446,7 @@ def _get_adjustment() -> Union[TextAdjustment, EastAsianTextAdjustment]:
 
 class TableFormatter:
 
-    show_dimensions = None
+    show_dimensions = None  # type: bool
     is_truncated = None
     formatters = None  # type: formatters_type
     columns = None  # type: Index
@@ -501,7 +501,7 @@ def __init__(
         max_rows: Optional[int] = None,
         min_rows: Optional[int] = None,
         max_cols: Optional[int] = None,
-        show_dimensions: Union[bool, str] = False,
+        show_dimensions: bool = False,
         decimal: str = ".",
         table_id: Optional[str] = None,
         render_links: bool = False,

From e955a52b470162d0b42149c63e65ba0ecefa1692 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 21:59:04 +0100
Subject: [PATCH 17/35] pandas\io\formats\format.py:574: error: Unsupported
 operand types for + ("List[str]" and "int")

---
 pandas/io/formats/format.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index cd2d7f3751f76..fd4457c625acb 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -571,6 +571,9 @@ def _chk_truncate(self) -> None:
                 prompt_row = 1
                 if self.show_dimensions:
                     show_dimension_rows = 3
+                # assume we only get here if self.header is boolean.
+                # i.e. not to_latex() where self.header may be List[str]
+                self.header = cast(bool, self.header)
                 n_add_rows = self.header + dot_row + show_dimension_rows + prompt_row
                 # rows available to fill with actual data
                 max_rows_adj = self.h - n_add_rows

From 32de27bd26fe251d90b271b0993b14d30c56b3ee Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 22:11:03 +0100
Subject: [PATCH 18/35] pandas\io\formats\format.py:594: error: Incompatible
 types in assignment (expression has type "Optional[int]", variable has type
 "int")

---
 pandas/io/formats/format.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index fd4457c625acb..c06c120738e93 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -576,7 +576,7 @@ def _chk_truncate(self) -> None:
                 self.header = cast(bool, self.header)
                 n_add_rows = self.header + dot_row + show_dimension_rows + prompt_row
                 # rows available to fill with actual data
-                max_rows_adj = self.h - n_add_rows
+                max_rows_adj = self.h - n_add_rows  # type: Optional[int]
                 self.max_rows_adj = max_rows_adj
 
             # Format only rows and columns that could potentially fit the

From 5802c0e1d33e4ba567c2498884d8d239517f36c6 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 22:22:11 +0100
Subject: [PATCH 19/35] pandas\io\formats\format.py:610: error: Incompatible
 types in assignment (expression has type "Optional[int]", variable has type
 "int")

---
 pandas/io/formats/format.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index c06c120738e93..dbf1d3683e07a 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -603,9 +603,12 @@ def _chk_truncate(self) -> None:
 
         frame = self.frame
         if truncate_h:
+            # cast here since if truncate_h is True, max_cols_adj is not None
+            max_cols_adj = cast(int, max_cols_adj)
             if max_cols_adj == 0:
                 col_num = len(frame.columns)
             elif max_cols_adj == 1:
+                max_cols = cast(int, max_cols)
                 frame = frame.iloc[:, :max_cols]
                 col_num = max_cols
             else:

From b82a952ca7d13e7f80929571518056e11010af2a Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 22:24:20 +0100
Subject: [PATCH 20/35] pandas\io\formats\format.py:625: error: Unsupported
 operand types for // ("None" and "int")

---
 pandas/io/formats/format.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index dbf1d3683e07a..262f339000f3b 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -618,6 +618,8 @@ def _chk_truncate(self) -> None:
                 )
             self.tr_col_num = col_num
         if truncate_v:
+            # cast here since if truncate_v is True, max_rows_adj is not None
+            max_rows_adj = cast(int, max_rows_adj)
             if max_rows_adj == 1:
                 row_num = max_rows
                 frame = frame.iloc[:max_rows, :]

From 31080c7a706fa898a86aa4e5e9faf0b78a791a6c Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 22:29:07 +0100
Subject: [PATCH 21/35] pandas\io\formats\format.py:636: error: Incompatible
 types in assignment (expression has type "Optional[int]", variable has type
 "None")

---
 pandas/io/formats/format.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 262f339000f3b..1f794bdaebaee 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -447,7 +447,7 @@ def _get_adjustment() -> Union[TextAdjustment, EastAsianTextAdjustment]:
 class TableFormatter:
 
     show_dimensions = None  # type: bool
-    is_truncated = None
+    is_truncated = None  # type: bool
     formatters = None  # type: formatters_type
     columns = None  # type: Index
 
@@ -633,7 +633,7 @@ def _chk_truncate(self) -> None:
         self.tr_frame = frame
         self.truncate_h = truncate_h
         self.truncate_v = truncate_v
-        self.is_truncated = self.truncate_h or self.truncate_v
+        self.is_truncated = bool(self.truncate_h or self.truncate_v)
 
     def _to_str_columns(self) -> List[List[str]]:
         """

From f0dc771a43d1fb509ad26353d547979ae45f5f01 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 23:20:49 +0100
Subject: [PATCH 22/35] pandas\io\formats\format.py:651: error: Argument
 "minimum" to "_make_fixed_width" has incompatible type "Union[str, int]";
 expected "Optional[int]"

---
 pandas/io/formats/format.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 1f794bdaebaee..c9cff96f26c38 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -95,7 +95,7 @@
             Formatter functions to apply to columns' elements by position or
             name.
             The result of each function must be a unicode string.
-            List must be of length equal to the number of columns.
+            List/tuple must be of length equal to the number of columns.
         float_format : one-parameter function, optional, default None
             Formatter function to apply to columns' elements if they are
             floats. The result of this function must be a unicode string.
@@ -639,6 +639,10 @@ def _to_str_columns(self) -> List[List[str]]:
         """
         Render a DataFrame to a list of columns (as lists of strings).
         """
+        # this method is not used by to_html where self.col_space
+        # could be a string so safe to cast
+        self.col_space = cast(int, self.col_space)
+
         frame = self.tr_frame
         # may include levels names also
 

From bd7887cd25e7bda30527b6951384a02ea9ddf619 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 23:27:14 +0100
Subject: [PATCH 23/35] pandas\io\formats\format.py:664: error: Argument 1 to
 "len" has incompatible type "Union[bool, List[str]]"; expected "Sized"

---
 pandas/io/formats/format.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index c9cff96f26c38..36ff5b8cee522 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -661,6 +661,8 @@ def _to_str_columns(self) -> List[List[str]]:
                 stringified.append(fmt_values)
         else:
             if is_list_like(self.header):
+                # cast here since can't be bool if is_list_like
+                self.header = cast(List[str], self.header)
                 if len(self.header) != len(self.columns):
                     raise ValueError(
                         (

From cfc1806f2bb093f81cd764e5499f65c9f3fcee68 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 23:37:46 +0100
Subject: [PATCH 24/35] pandas\io\formats\format.py:714: error: Invalid index
 type "Optional[int]" for "Union[Any, List[str]]"; expected type "int"

---
 pandas/io/formats/format.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 36ff5b8cee522..d31a3addc369d 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -709,6 +709,8 @@ def _to_str_columns(self) -> List[List[str]]:
         if truncate_v:
             n_header_rows = len(str_index) - len(frame)
             row_num = self.tr_row_num
+            # cast here since if truncate_v is True, self.tr_row_num is not None
+            row_num = cast(int, row_num)
             for ix, col in enumerate(strcols):
                 # infer from above row
                 cwidth = self.adj.len(strcols[ix][row_num])

From 2a429f64b8ef45d289d124bae3a20ffb6d88ef34 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 23:43:03 +0100
Subject: [PATCH 25/35] pandas\io\formats\format.py:762: error: Incompatible
 types in assignment (expression has type "List[str]", variable has type
 "str")

---
 pandas/io/formats/format.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index d31a3addc369d..463dcab65ac39 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -759,8 +759,8 @@ def to_string(self) -> None:
             ):  # need to wrap around
                 text = self._join_multiline(*strcols)
             else:  # max_cols == 0. Try to fit frame to terminal
-                text = self.adj.adjoin(1, *strcols).split("\n")
-                max_len = Series(text).str.len().max()
+                lines = self.adj.adjoin(1, *strcols).split("\n")
+                max_len = Series(lines).str.len().max()
                 # plus truncate dot col
                 dif = max_len - self.w
                 # '+ 1' to avoid too wide repr (GH PR #17023)

From 02c364a8e9bd98d89cd1730e4cc551d882cfc5a9 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 23:44:03 +0100
Subject: [PATCH 26/35] pandas\io\formats\format.py:803: error: Incompatible
 types in assignment (expression has type "List[Any]", variable has type
 "Tuple[Any, ...]")

---
 pandas/io/formats/format.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 463dcab65ac39..fca5132fd466e 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -797,10 +797,10 @@ def to_string(self) -> None:
                 )
             )
 
-    def _join_multiline(self, *strcols) -> str:
+    def _join_multiline(self, *args) -> str:
         lwidth = self.line_width
         adjoin_width = 1
-        strcols = list(strcols)
+        strcols = list(args)
         if self.index:
             idx = strcols.pop(0)
             lwidth -= np.array([self.adj.len(x) for x in idx]).max() + adjoin_width

From 9d2a734c2937afc6054a28c2dc05ec2c3852f20b Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 23:46:51 +0100
Subject: [PATCH 27/35] pandas\io\formats\format.py:816: error: Unsupported
 operand types for + ("None" and "int")

---
 pandas/io/formats/format.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index fca5132fd466e..48ab1f7abd4e9 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -813,6 +813,8 @@ def _join_multiline(self, *args) -> str:
         nbins = len(col_bins)
 
         if self.truncate_v:
+            # cast here since if truncate_v is True, max_rows_adj is not None
+            self.max_rows_adj = cast(int, self.max_rows_adj)
             nrows = self.max_rows_adj + 1
         else:
             nrows = len(self.frame)

From a70080b36845b02f0f6ac0c6927434b3c55c83dd Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 23:50:13 +0100
Subject: [PATCH 28/35] pandas\io\formats\format.py:997: error: Argument
 "minimum" to "_make_fixed_width" has incompatible type "Union[str, int]";
 expected "Optional[int]"

---
 pandas/io/formats/format.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 48ab1f7abd4e9..270c74a236ff6 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -977,7 +977,8 @@ def show_col_idx_names(self) -> bool:
 
     def _get_formatted_index(self, frame: "DataFrame") -> List[str]:
         # Note: this is only used by to_string() and to_latex(), not by
-        # to_html().
+        # to_html(). so safe to cast col_space here.
+        self.col_space = cast(int, self.col_space)
         index = frame.index
         columns = frame.columns
         fmt = self._get_formatter("__index__")

From 5d2c6806048d7373ce73c13c6aba2e4ae7170015 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sun, 21 Jul 2019 23:53:16 +0100
Subject: [PATCH 29/35] pandas\io\formats\format.py:1075: error: Incompatible
 types in assignment (expression has type "Type[Timedelta64Formatter]",
 variable has type "Type[Datetime64Formatter]")

---
 pandas/io/formats/format.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 270c74a236ff6..2281992d5350a 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -1068,7 +1068,7 @@ def format_array(
     """
 
     if is_datetime64_dtype(values.dtype):
-        fmt_klass = Datetime64Formatter
+        fmt_klass = Datetime64Formatter  # type: Type[GenericArrayFormatter]
     elif is_datetime64tz_dtype(values):
         fmt_klass = Datetime64TZFormatter
     elif is_timedelta64_dtype(values.dtype):

From 660136a94a9a154168bdf1593b4089e590b938b9 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Mon, 22 Jul 2019 00:04:46 +0100
Subject: [PATCH 30/35] pandas\io\formats\format.py:1232: error: Incompatible
 types in assignment (expression has type "Union[str, Callable[..., Any],
 EngFormatter, Type[str], None]", variable has type "Union[Callable[..., Any],
 partial[Any], None]")

---
 pandas/io/formats/format.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 2281992d5350a..3fdae18508a58 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -75,6 +75,7 @@
 formatters_type = Union[
     List[Callable], Tuple[Callable, ...], Dict[Union[str, int], Callable]
 ]
+float_format_type = Union[str, Callable[..., Any], "EngFormatter", Type[str]]
 
 common_docstring = """
         Parameters
@@ -1114,7 +1115,7 @@ def __init__(
         formatter: Optional[Union[Callable, Type[str]]] = None,
         na_rep: str = "NaN",
         space: Union[str, int] = 12,
-        float_format: Optional[Union[str, Callable, "EngFormatter", Type[str]]] = None,
+        float_format: Optional[float_format_type] = None,
         justify: str = "right",
         decimal: str = ".",
         quoting: Optional[int] = None,
@@ -1221,7 +1222,7 @@ def __init__(self, *args, **kwargs) -> None:
 
     def _value_formatter(
         self,
-        float_format: Optional[Union[Callable, partial]] = None,
+        float_format: Optional[float_format_type] = None,
         threshold: Optional[Union[float, int]] = None,
     ) -> Callable:
         """Returns a function to be applied on each value to format it

From 80922a38b28854b5da3d97d555bf2eb922d328dd Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Mon, 22 Jul 2019 00:08:43 +0100
Subject: [PATCH 31/35] pandas\io\formats\format.py:1326: error: Incompatible
 types in assignment (expression has type "None", variable has type
 "partial[str]")

---
 pandas/io/formats/format.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index 3fdae18508a58..d307afad0e0c7 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -1322,7 +1322,7 @@ def format_values_with(float_format):
             if self.fixed_width:
                 float_format = partial(
                     "{value: .{digits:d}f}".format, digits=self.digits
-                )
+                )  # type: Optional[float_format_type]
             else:
                 float_format = self.float_format
         else:

From 4aae208b5461bd734e3ea76ce0b1fa6a907044b3 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Mon, 22 Jul 2019 00:42:38 +0100
Subject: [PATCH 32/35] pandas\io\formats\html.py:86: error: Signature of
 "is_truncated" incompatible with supertype "TableFormatter"

---
 pandas/io/formats/html.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/pandas/io/formats/html.py b/pandas/io/formats/html.py
index 91e90a78d87a7..56c58a1b1363f 100644
--- a/pandas/io/formats/html.py
+++ b/pandas/io/formats/html.py
@@ -82,8 +82,9 @@ def row_levels(self) -> int:
     def _get_columns_formatted_values(self) -> Iterable:
         return self.columns
 
+    # https://github.com/python/mypy/issues/1237
     @property
-    def is_truncated(self) -> bool:
+    def is_truncated(self) -> bool:  # type: ignore
         return self.fmt.is_truncated
 
     @property

From 8fa7b2912b60dccefac1cf61d8a98346e147ce58 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Mon, 22 Jul 2019 00:47:14 +0100
Subject: [PATCH 33/35] pandas\io\formats\html.py:466: error: Unsupported
 operand types for >= ("int" and "None")

---
 pandas/io/formats/html.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/pandas/io/formats/html.py b/pandas/io/formats/html.py
index 56c58a1b1363f..19305126f4e5f 100644
--- a/pandas/io/formats/html.py
+++ b/pandas/io/formats/html.py
@@ -4,7 +4,7 @@
 
 from collections import OrderedDict
 from textwrap import dedent
-from typing import Any, Dict, Iterable, List, Optional, Tuple, Union
+from typing import Any, Dict, Iterable, List, Optional, Tuple, Union, cast
 
 from pandas._config import get_option
 
@@ -459,6 +459,8 @@ def _write_hierarchical_rows(
                 # Insert ... row and adjust idx_values and
                 # level_lengths to take this into account.
                 ins_row = self.fmt.tr_row_num
+                # cast here since if truncate_v is True, self.fmt.tr_row_num is not None
+                ins_row = cast(int, ins_row)
                 inserted = False
                 for lnum, records in enumerate(level_lengths):
                     rec_new = {}

From bb15c301b56630f9748a5d7273a5cbc0125bfbc5 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Mon, 22 Jul 2019 00:52:26 +0100
Subject: [PATCH 34/35] remove None return types from __init__ (automatically
 reapplied by monkeytype)

---
 pandas/io/formats/format.py | 22 ++++++++++------------
 1 file changed, 10 insertions(+), 12 deletions(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index d307afad0e0c7..f2c967cce21ae 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -164,7 +164,7 @@ def __init__(
         length: bool = True,
         na_rep: str = "NaN",
         footer: bool = True,
-    ) -> None:
+    ):
         self.categorical = categorical
         self.buf = buf if buf is not None else StringIO("")
         self.na_rep = na_rep
@@ -233,7 +233,7 @@ def __init__(
         dtype: bool = True,
         max_rows: Optional[int] = None,
         min_rows: Optional[int] = None,
-    ) -> None:
+    ):
         self.series = series
         self.buf = buf if buf is not None else StringIO()
         self.name = name
@@ -377,7 +377,7 @@ def to_string(self) -> str:
 
 
 class TextAdjustment:
-    def __init__(self) -> None:
+    def __init__(self):
         self.encoding = get_option("display.encoding")
 
     def len(self, text: Union[str_, str]) -> int:
@@ -391,7 +391,7 @@ def adjoin(self, space: int, *lists, **kwargs) -> str:
 
 
 class EastAsianTextAdjustment(TextAdjustment):
-    def __init__(self) -> None:
+    def __init__(self):
         super().__init__()
         if get_option("display.unicode.ambiguous_as_wide"):
             self.ambiguous_width = 2
@@ -507,7 +507,7 @@ def __init__(
         table_id: Optional[str] = None,
         render_links: bool = False,
         **kwds
-    ) -> None:
+    ):
         self.frame = frame
         if buf is not None:
             self.buf = _expand_user(_stringify_path(buf))
@@ -1121,7 +1121,7 @@ def __init__(
         quoting: Optional[int] = None,
         fixed_width: bool = True,
         leading_space: Optional[bool] = None,
-    ) -> None:
+    ):
         self.values = values
         self.digits = digits
         self.na_rep = na_rep
@@ -1208,7 +1208,7 @@ class FloatArrayFormatter(GenericArrayFormatter):
 
     """
 
-    def __init__(self, *args, **kwargs) -> None:
+    def __init__(self, *args, **kwargs):
         GenericArrayFormatter.__init__(self, *args, **kwargs)
 
         # float_format is expected to be a string
@@ -1381,7 +1381,7 @@ def __init__(
         nat_rep: str = "NaT",
         date_format: None = None,
         **kwargs
-    ) -> None:
+    ):
         super().__init__(values, **kwargs)
         self.nat_rep = nat_rep
         self.date_format = date_format
@@ -1602,7 +1602,7 @@ def __init__(
         nat_rep: str = "NaT",
         box: bool = False,
         **kwargs
-    ) -> None:
+    ):
         super().__init__(values, **kwargs)
         self.nat_rep = nat_rep
         self.box = box
@@ -1772,9 +1772,7 @@ class EngFormatter:
         24: "Y",
     }
 
-    def __init__(
-        self, accuracy: Optional[int] = None, use_eng_prefix: bool = False
-    ) -> None:
+    def __init__(self, accuracy: Optional[int] = None, use_eng_prefix: bool = False):
         self.accuracy = accuracy
         self.use_eng_prefix = use_eng_prefix
 

From 63aa725e1a80354aa26bdd1a210d7bee18ab424b Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Mon, 22 Jul 2019 01:59:21 +0100
Subject: [PATCH 35/35] simplify some unions

---
 pandas/io/formats/format.py | 44 ++++++++++++++-----------------------
 1 file changed, 17 insertions(+), 27 deletions(-)

diff --git a/pandas/io/formats/format.py b/pandas/io/formats/format.py
index f2c967cce21ae..c5b0b7b222e27 100644
--- a/pandas/io/formats/format.py
+++ b/pandas/io/formats/format.py
@@ -4,13 +4,14 @@
 """
 
 from functools import partial
-from io import StringIO, TextIOWrapper
+from io import StringIO
 from shutil import get_terminal_size
 from typing import (
     TYPE_CHECKING,
     Any,
     Callable,
     Dict,
+    Iterable,
     List,
     Optional,
     TextIO,
@@ -21,12 +22,10 @@
 )
 from unicodedata import east_asian_width
 
-from _pytest.capture import EncodedFile
 from dateutil.tz.tz import tzutc
 from dateutil.zoneinfo import tzfile
 import numpy as np
-from numpy import float64, int32, ndarray, str_
-from py._path.local import LocalPath
+from numpy import float64, int32, ndarray
 
 from pandas._config.config import get_option, set_option
 
@@ -58,6 +57,7 @@
 )
 from pandas.core.dtypes.missing import isna, notna
 
+from pandas._typing import FilePathOrBuffer
 from pandas.core.arrays.datetimes import DatetimeArray
 from pandas.core.arrays.timedeltas import TimedeltaArray
 from pandas.core.base import PandasObject
@@ -75,7 +75,7 @@
 formatters_type = Union[
     List[Callable], Tuple[Callable, ...], Dict[Union[str, int], Callable]
 ]
-float_format_type = Union[str, Callable[..., Any], "EngFormatter", Type[str]]
+float_format_type = Union[str, Callable, "EngFormatter"]
 
 common_docstring = """
         Parameters
@@ -380,7 +380,7 @@ class TextAdjustment:
     def __init__(self):
         self.encoding = get_option("display.encoding")
 
-    def len(self, text: Union[str_, str]) -> int:
+    def len(self, text: str) -> int:
         return len(text)
 
     def justify(self, texts: Any, max_len: int, mode: str = "right") -> List[str]:
@@ -415,15 +415,7 @@ def len(self, text: str) -> int:
         )
 
     def justify(
-        self,
-        texts: Union[
-            Tuple[str, str],
-            List[str],
-            Tuple[str, str, str, str, str],
-            Tuple[str, str, str, str],
-        ],
-        max_len: int,
-        mode: str = "right",
+        self, texts: Iterable[str], max_len: int, mode: str = "right"
     ) -> List[str]:
         # re-calculate padding space per str considering East Asian Width
         def _get_pad(t):
@@ -437,7 +429,7 @@ def _get_pad(t):
             return [x.rjust(_get_pad(x)) for x in texts]
 
 
-def _get_adjustment() -> Union[TextAdjustment, EastAsianTextAdjustment]:
+def _get_adjustment() -> TextAdjustment:
     use_east_asian_width = get_option("display.unicode.east_asian_width")
     if use_east_asian_width:
         return EastAsianTextAdjustment()
@@ -487,15 +479,15 @@ class DataFrameFormatter(TableFormatter):
     def __init__(
         self,
         frame: "DataFrame",
-        buf: Optional[Union[StringIO, LocalPath, str]] = None,
+        buf: Optional[FilePathOrBuffer] = None,
         columns: Optional[List[str]] = None,
         col_space: Optional[Union[str, int]] = None,
         header: Union[bool, List[str]] = True,
-        index: Union[bool, int] = True,
+        index: bool = True,
         na_rep: str = "NaN",
         formatters: Optional[formatters_type] = None,
         justify: Optional[str] = None,
-        float_format: Optional[Union[str, Type[str]]] = None,
+        float_format: Optional[float_format_type] = None,
         sparsify: Optional[bool] = None,
         index_names: bool = True,
         line_width: Optional[int] = None,
@@ -1032,8 +1024,8 @@ def _get_column_name_list(self) -> List[str]:
 
 def format_array(
     values: Any,
-    formatter: Optional[Union[Callable, Type[str]]],
-    float_format: Optional[Union[Callable, str, Type[str]]] = None,
+    formatter: Optional[Callable],
+    float_format: Optional[float_format_type] = None,
     na_rep: str = "NaN",
     digits: Optional[int] = None,
     space: Optional[Union[str, int]] = None,
@@ -1112,7 +1104,7 @@ def __init__(
         self,
         values: Any,
         digits: int = 7,
-        formatter: Optional[Union[Callable, Type[str]]] = None,
+        formatter: Optional[Callable] = None,
         na_rep: str = "NaN",
         space: Union[str, int] = 12,
         float_format: Optional[float_format_type] = None,
@@ -1661,10 +1653,10 @@ def _formatter(x):
 
 
 def _make_fixed_width(
-    strings: Union[ndarray, List[str], List[str_]],
+    strings: Union[ndarray, List[str]],
     justify: str = "right",
     minimum: Optional[int] = None,
-    adj: Optional[Union[TextAdjustment, EastAsianTextAdjustment]] = None,
+    adj: Optional[TextAdjustment] = None,
 ) -> Union[ndarray, List[str]]:
 
     if len(strings) == 0 or justify == "all":
@@ -1918,9 +1910,7 @@ def get_level_lengths(
     return result
 
 
-def buffer_put_lines(
-    buf: Union[StringIO, TextIOWrapper, EncodedFile], lines: List[str]
-) -> None:
+def buffer_put_lines(buf: TextIO, lines: List[str]) -> None:
     """
     Appends lines to a buffer.