From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jonathan Nieder <jrnieder@gmail.com>
Subject: Re: [PATCH] fast-import: catch deletion of non-existent file in input
Date: Sun, 15 Jul 2012 13:11:51 -0500
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Cc: Andreas Schwab <schwab@linux-m68k.org>,
	"Shawn O. Pearce" <spearce@spearce.org>,
	David Barr <davidbarr@google.com>,
	Felix Natter <fnatter@gmx.net>, git@vger.kernel.org
To: Jeff King <peff@peff.net>
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Hi,

Jeff King wrote:

> Subject: fast-import: catch deletion of non-existent file in input
[...]
> We silently ignored the bogus "D foo" directive, and the
> resulting tree incorrectly contained "bar". With this patch,
> we notice the bogus input and die.

This breaks svn-fe, which relies on the existing semantics when asked
to copy an empty directory.

That's my fault because we never check that in the testsuite, but I
also wouldn't be surprised if other importers were relying on the same
thing.

Any API break this big without a justification along the lines

	We can be confident that no existing importer uses this
	construct because ...

_needs_ to be guarded by a new "feature" to be safe for existing
importers.

Let's repeat that for emphasis: API breaks in fast-import not guarded
with a new "feature" type are not ok.

Sorry,
Jonathan