Enhancement request: option to specify whether # is followed by space

[edreamleo]

I am the author of Leo. At present, black inserts a blank between "#" and "@". Alas, this seriously interferes with Leo's 20-year-old format for sentinel comments.

This post discusses all the gory details. The take-away is that Leo has is no good solution to the problem.

Happily, there is a dead easy patch: In make_comment, change:

if content and content[0] not in " !:#'%":
    content = " " + content

to:

if content and content[0] not in " @!:#'%": # EKR: This string would better be an option.
    content = " " + content

Better, the option could be a regex, specifying the exact exceptions.

I hope you will consider adding such an option. Even a non-regex option would make a big difference.

Edward

P.S. For Leo, the regex would be the union of the following :-)

ref = g.angleBrackets(r'(.*)') # Yields << \1 >>, which is special Leo syntax.
delim1, delim2 = '#', ''
patterns = (
    # These patterns must be mutually exclusive.
    fr'^\s*{delim1}@afterref{delim2}$',             # @afterref
    fr'^(\s*){delim1}@(\+|-)all\b(.*){delim2}$',    # @all
    fr'^\s*{delim1}@@c(ode)?{delim2}$',             # @c and @code
    fr'^\s*{delim1}@comment(.*){delim2}',           # @comment
    fr'^\s*{delim1}@delims(.*){delim2}',            # @delims
    fr'^\s*{delim1}@\+(at|doc)?(\s.*?)?{delim2}\n', # @doc or @
    fr'^\s*{delim1}@end_raw\s*{delim2}',            # @end_raw
    fr'^\s*{delim1}@@first{delim2}$',               # @first
    fr'^\s*{delim1}@@last{delim2}$',                # @last
    fr'^(\s*){delim1}@\+node:([^:]+): \*(\d+)?(\*?) (.*){delim2}$', # @node
    fr'^(\s*){delim1}@(\+|-)others\b(.*){delim2}$', # @others
    fr'^\s*{delim1}@raw(.*){delim2}',               # @raw
    fr'^(\s*){delim1}@(\+|-){ref}\s*{delim2}$'      # section ref
)

EKR

[JelleZijlstra]

Related: #960

[edreamleo]

@JelleZijlstra Thanks for the link. Imo, black should have more options. More people will use black if they can configure it so it works for them, their team, their organization.

[JelleZijlstra]

Let's take a decision in #3668.

[edreamleo]

@JelleZijlstra I agree that none of the options discussed in #3668 are perfect. Most projects should be able to find a way of living with Black's formatting of comments. For example:

• Leo has long been able to read blackened sentinel comments.
• Leo's newish --black-sentinels command-line option causes Leo to write black-compatible sentinel comments.