Re: [PATCH] userdiff: add support for Swift

[Junio C Hamano <gitster@pobox.com>]

Johannes Sixt <j6t@kdbg.org> writes:

> Am 17.07.26 um 16:02 schrieb Shlok Kulshreshtha:
>> Add a built-in userdiff driver for the Swift programming language so that
>> diff hunk headers and word diffs work out of the box for ".swift" files.
>> 
>> The funcname pattern is built for Swift's own declaration grammar: an
>> optional run of attributes ("@objc", "@available(iOS 13, *)", ...),
>> followed by an optional run of lowercase modifiers ("public", "static",
>> "final", ...), followed by a declaration keyword (func, class, struct,
>> enum, protocol, extension, actor, init, deinit, subscript). The keyword
>> is followed by a boundary that allows whitespace, "(" (init/subscript),
>> "?" or "!" (failable init), or "<" (generics), while still acting as a
>> word boundary so e.g. "initialize(" does not match.
>> 
>> The word regex recognizes Swift identifiers, hexadecimal, octal, binary,
>> integer and floating-point literals, and the language's operators.
>> 
>> Signed-off-by: Shlok Kulshreshtha <diy2903@gmail.com>
>> ---
>> This addresses the "add a userdiff driver for a language" microproject.
>
> I am mildly surprised that userdiff drivers can count as microproject.
> At a minimum, they are on the challenging side of the spectrum.

I am, too ;-)  It is hard to get them right, even though thanks to
your earlier work long time ago, writing a test that demonstrates
what is expected of the patterns is fairly easy to write.