Re: [PATCH v3] userdiff: add built-in pattern for rust

["Marc-André Lureau" <marcandre.lureau@redhat.com>]

Hi

On Mon, May 20, 2019 at 9:52 PM Johannes Sixt <j6t@kdbg.org> wrote:
>
> Am 20.05.19 um 19:04 schrieb marcandre.lureau@redhat.com:
> > From: Marc-André Lureau <mlureau@redhat.com>
> >
> > This adds xfuncname and word_regex patterns for Rust, a quite
> > popular programming language. It also includes test cases for the
> > xfuncname regex (t4018) and updated documentation.
> >
> > The word_regex pattern finds identifiers, integers, floats and
> > operators, according to the Rust Reference Book.
>
> This looks very good. I have a few questions regarding the hunk header
> regex.
>
> > diff --git a/userdiff.c b/userdiff.c
> > index 3a78fbf504..e45b5920c6 100644
> > --- a/userdiff.c
> > +++ b/userdiff.c
> > @@ -130,6 +130,12 @@ PATTERNS("ruby", "^[ \t]*((class|module|def)[ \t].*)$",
> >        "(@|@@|\\$)?[a-zA-Z_][a-zA-Z0-9_]*"
> >        "|[-+0-9.e]+|0[xXbB]?[0-9a-fA-F]+|\\?(\\\\C-)?(\\\\M-)?."
> >        "|//=?|[-+*/<>%&^|=!]=|<<=?|>>=?|===|\\.{1,3}|::|[!=]~"),
> > +PATTERNS("rust",
> > +      "^[\t ]*((pub(\\([^\\)]+\\))?[\t ]+)?((async|const|unsafe|extern([\t ]+\"[^\"]+\"))[\t ]+)?(struct|enum|union|mod|trait|fn|impl(<.+>)?)[ \t]+[^;]*)$",
>
> This pattern matches only if there is no semicolon behind the signal
> words on the line. Is that important? Can you show a (test) case where a
> line with a semicolon would be picked incorrectly if '[^;]*' were
> simplified to '.*'?


Ok, I am adding:

trait RIGHT {

    fn new(name: &'static str) -> Self;

    fn ChangeMe(&self) {
        // should skip "new", and return trait name
    }
}

> You permit whitespace at the beginning of an anchor line. I guess that
> is to catch nested definitions. Or is it common style to write indented
> code? Can you show a test case where this makes sense?
>

sure, I thought it was already covered.

fn foo() {
    fn RIGHT() {
        // must catch nested function
        ChangeMe;
    }
}

(a simpler example would be a method implementation)

> Would it be sufficient to simplify
>
>     (struct|enum|union|mod|trait|fn|impl(<.+>)?)[ \t]+
> to
>     (struct|enum|union|mod|trait|fn|impl)[< \t]+
>
> as it is only important to exclude identifiers that start with these
> keywords.

I think that would be fine, ok I am changing it

>
> > +      /* -- */
> > +      "[a-zA-Z_][a-zA-Z0-9_]*"
> > +      "|[0-9][0-9_a-fA-Fiosuxz]*(\\.([0-9]*[eE][+-]?)?[0-9_fF]*)?"
> > +      "|[-+*\\/<>%&^|=!:]=|<<=?|>>=?|&&|\\|\\||->|=>|\\.{2}=|\\.{3}|::"),
> >  PATTERNS("bibtex", "(@[a-zA-Z]{1,}[ \t]*\\{{0,1}[ \t]*[^ \t\"@',\\#}{~%]*).*$",
> >        "[={}\"]|[^={}\" \t]+"),
> >  PATTERNS("tex", "^(\\\\((sub)*section|chapter|part)\\*{0,1}\\{.*)$",
> >
> > base-commit: aa25c82427ae70aebf3b8f970f2afd54e9a2a8c6
>
> -- Hannes