import io
from datetime import datetime
from typing import Any, List
from dataproperty import ColumnDataProperty, DataProperty, DefaultValue
from typepy import StrictLevel, Typecode
from ...._converter import strip_quote
from ...._function import quote_datetime_formatter
from ....sanitizer import sanitize_js_var_name
from .._common import bool_to_str
from ._sourcecode import SourceCodeTableWriter
def js_datetime_formatter(value: datetime) -> str:
try:
return f'new Date("{value.strftime(DefaultValue.DATETIME_FORMAT):s}")'
except ValueError:
# the datetime strftime() methods require year >= 1900
return f'new Date("{value}")'
[docs]
class JavaScriptTableWriter(SourceCodeTableWriter):
"""
A table writer for class JavaScript format.
:Example:
:ref:`example-js-table-writer`
.. py:attribute:: variable_declaration
:type: str
:value: "const"
JavaScript variable declarations type.
The value must be either ``"var"``, ``"let"`` or ``"const"``.
.. py:method:: write_table
|write_table| with JavaScript format.
The tabular data are written as a nested list variable definition.
:raises pytablewriter.EmptyTableNameError:
If the |table_name| is empty.
:Example:
:ref:`example-js-table-writer`
.. note::
Specific values in the tabular data are converted when writing:
- |None|: written as ``null``
- |inf|: written as ``Infinity``
- |nan|: written as ``NaN``
- |datetime| instances determined by |is_datetime_instance_formatting| attribute:
- |True|: written as `dateutil.parser <https://dateutil.readthedocs.io/en/stable/parser.html>`__
- |False|: written as |str|
.. seealso::
:ref:`example-type-hint-js`
"""
FORMAT_NAME = "javascript"
__VALID_VAR_DECLARATION = ("var", "let", "const")
__NONE_VALUE_DP = DataProperty("null")
@property
def format_name(self) -> str:
return self.FORMAT_NAME
@property
def support_split_write(self) -> bool:
return True
@property
def variable_declaration(self) -> str:
return self.__variable_declaration
@variable_declaration.setter
def variable_declaration(self, value: str) -> None:
value = value.strip().casefold()
if value not in self.__VALID_VAR_DECLARATION:
raise ValueError("declaration must be either var, let or const")
self.__variable_declaration = value
def __init__(self, **kwargs: Any) -> None:
super().__init__(**kwargs)
self.variable_declaration = "const"
self._dp_extractor.type_value_map = {
# Typecode.NONE: "null",
Typecode.INFINITY: "Infinity",
Typecode.NAN: "NaN",
}
self._dp_extractor.update_strict_level_map({Typecode.BOOL: StrictLevel.MAX})
self.register_trans_func(bool_to_str)
def get_variable_name(self, value: str) -> str:
return sanitize_js_var_name(value, "_").casefold()
def _write_table(self, **kwargs: Any) -> None:
if self.is_datetime_instance_formatting:
self._dp_extractor.datetime_formatter = js_datetime_formatter
else:
self._dp_extractor.datetime_formatter = quote_datetime_formatter
org_stream = self.stream
self.stream = io.StringIO()
self.inc_indent_level()
super()._write_table(**kwargs)
self.dec_indent_level()
js_matrix_var_def_text = self.stream.getvalue().rstrip("\n")
js_matrix_var_def_text = strip_quote(js_matrix_var_def_text, "true")
js_matrix_var_def_text = strip_quote(js_matrix_var_def_text, "false")
if self.is_write_closing_row:
js_matrix_var_def_line_list = js_matrix_var_def_text.splitlines()
js_matrix_var_def_line_list[-2] = js_matrix_var_def_line_list[-2].rstrip(",")
js_matrix_var_def_text = "\n".join(js_matrix_var_def_line_list)
self.stream.close()
self.stream = org_stream
self.dec_indent_level()
self._write_line(js_matrix_var_def_text)
self.inc_indent_level()
def _get_opening_row_items(self) -> List[str]:
return [f"{self.variable_declaration:s} {self.variable_name:s} = ["]
def _get_closing_row_items(self) -> List[str]:
return ["];"]
def _to_row_item(self, row_idx: int, col_dp: ColumnDataProperty, value_dp: DataProperty) -> str:
if value_dp.data is None:
value_dp = self.__NONE_VALUE_DP
return super()._to_row_item(row_idx, col_dp, value_dp)