[PATCH 3 of 3 V4] revset: add a followlines(file, fromline, toline[, rev]) revset

[Yuya Nishihara]

On Wed, 04 Jan 2017 17:03:49 +0100, Denis Laxalde wrote:
> # HG changeset patch
> # User Denis Laxalde <denis.laxalde at logilab.fr>
> # Date 1483544869 -3600
> #      Wed Jan 04 16:47:49 2017 +0100
> # Node ID e36f0540260ec2bf9e3f324bc7839d5409a3314b
> # Parent  ae66a9ae337e267ecb47f8e2610c308fd81743b7
> # EXP-Topic linerange-log/revset
> revset: add a followlines(file, fromline, toline[, rev]) revset

Also looks good. I'll queue this.

> --- a/mercurial/revset.py
> +++ b/mercurial/revset.py
> @@ -1065,6 +1065,52 @@ def _followfirst(repo, subset, x):
>      # of every revisions or files revisions.
>      return _follow(repo, subset, x, '_followfirst', followfirst=True)
>  
> + at predicate('followlines(file, fromline, toline[, rev=.])', safe=True)

I slightly prefer "fromline:toline" than "fromline, toline". I'll take a look
how that will complicate things and hopefully will send a patch before the
freeze.

> +def followlines(repo, subset, x):
> +    """Changesets modifying `file` in line range ('fromline', 'toline').
> +
> +    Line range corresponds to 'file' content at 'rev' and should hence be
> +    consistent with file size. If rev is not specified, working directory's
> +    parent is used.
> +    """
> +    from . import context  # avoid circular import issues
> +
> +    args = getargs(x, 3, 4, _("followlines takes at least three arguments"))
> +
> +    rev = '.'
> +    if len(args) == 4:
> +        revarg = getargsdict(args[3], 'followlines', 'rev')
> +        if 'rev' in revarg:
> +            revs = getset(repo, fullreposet(repo), revarg['rev'])
> +            if len(revs) != 1:
> +                raise error.ParseError(
> +                    _("followlines expects exactly one revision"))
> +            rev = revs.last()
> +
> +    pat = getstring(args[0], _("followlines requires a pattern"))
> +    if not matchmod.patkind(pat):
> +        fname = pathutil.canonpath(repo.root, repo.getcwd(), pat)
> +    else:
> +        m = matchmod.match(repo.root, repo.getcwd(), [pat], ctx=repo[rev])
> +        files = [f for f in repo[rev] if m(f)]
> +        if len(files) != 1:
> +            raise error.ParseError(_("followlines expects exactly one file"))
> +        fname = files[0]
> +
> +    try:
> +        fromline, toline = [int(getsymbol(a)) for a in args[1:3]]