On Tue, Sep 22, 2020 at 05:00:32PM -0400, John Snow wrote:
> Code style tools really dislike the use of global keywords, because it
> generally involves re-binding the name at runtime which can have strange
> effects depending on when and how that global name is referenced in
> other modules.
>
> Make a little indent level manager instead.
>
> Signed-off-by: John Snow <[email protected]>
> ---
> scripts/qapi/common.py | 51 +++++++++++++++++++++++++++++-------------
> scripts/qapi/visit.py | 7 +++---
> 2 files changed, 38 insertions(+), 20 deletions(-)
>
> diff --git a/scripts/qapi/common.py b/scripts/qapi/common.py
> index cee63eb95c..e0c5871b10 100644
> --- a/scripts/qapi/common.py
> +++ b/scripts/qapi/common.py
> @@ -93,33 +93,52 @@ def c_name(name, protect=True):
> pointer_suffix = ' *' + eatspace
>
>
> -def genindent(count):
> - ret = ''
> - for _ in range(count):
> - ret += ' '
> - return ret
> +class Indentation:
> + """
> + Indentation level management.
>
> + :param initial: Initial number of spaces, default 0.
> + """
> + def __init__(self, initial: int = 0) -> None:
> + self._level = initial
>
> -indent_level = 0
> + def __int__(self) -> int:
> + return self._level
>
> + def __repr__(self) -> str:
> + return "{}({:d})".format(type(self).__name__, self._level)
>
> -def push_indent(indent_amount=4):
> - global indent_level
> - indent_level += indent_amount
> + def __str__(self) -> str:
> + """Return the current indentation as a string of spaces."""
> + return ' ' * self._level
>
> + def __bool__(self) -> bool:
> + """True when there is a non-zero indentation."""
> + return bool(self._level)
>
> -def pop_indent(indent_amount=4):
> - global indent_level
> - indent_level -= indent_amount
> + def increase(self, amount: int = 4) -> int:
> + """Increase the indentation level by `amount`, default 4."""
> + self._level += amount
> + return self._level
> +
> + def decrease(self, amount: int = 4) -> int:
> + """Decrease the indentation level by `amount`, default 4."""
> + if self._level < amount:
> + raise ArithmeticError(
> + f"Can't remove {amount:d} spaces from {self!r}")
> + self._level -= amount
> + return self._level
> +
> +
> +indent = Indentation()
Personally, I would keep the push_indent(), pop_indent() API, and
introduce an indent() function, to follow the existing API style
of plain functions.
Something like:
indent_prefixes = []
def push_indent(amount=4):
"""Add `amount` spaces to indentation prefix"""
indent_prefixes.push(' '*amount)
def pop_indent():
"""Revert the most recent push_indent() call"""
indent_prefixes.pop()
def indent():
"""Return the current indentation prefix"""
return ''.join(indent_prefixes)
What you did is still an improvement, though, so:
Reviewed-by: Eduardo Habkost <[email protected]>
--
Eduardo
