# [PATCH] mergetools/p4merge: Handle "/dev/null" 3 messages from 2012-10-11 to 2012-12-20. Participants: David Aguilar, Jeremy Morton. Thread: https://gitlist.dev/t/31784 ## David Aguilar, 2012-10-11 03:22 Subject: [PATCH] mergetools/p4merge: Handle "/dev/null" Message-ID: <1349925756-87801-1-git-send-email-davvid@gmail.com> URL: https://gitlist.dev/e/1349925756-87801-1-git-send-email-davvid%40gmail.com ``` p4merge does not properly handle the case where "/dev/null" is passed as a filename. Workaround it by creating a temporary file for this purpose. Reported-by: Jeremy Morton Signed-off-by: David Aguilar --- Jeremy, can you test this? mergetools/p4merge | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/mergetools/p4merge b/mergetools/p4merge index 1a45c1b..295361a 100644 --- a/mergetools/p4merge +++ b/mergetools/p4merge @@ -1,5 +1,30 @@ diff_cmd () { + # p4merge does not like /dev/null + rm_local= + rm_remote= + if test "/dev/null" = "$LOCAL" + then + LOCAL="./p4merge-dev-null.LOCAL.$$" + >"$LOCAL" + rm_local=true + fi + if test "/dev/null" = "$REMOTE" + then + REMOTE="./p4merge-dev-null.REMOTE.$$" + >"$REMOTE" + rm_remote=true + fi + "$merge_tool_path" "$LOCAL" "$REMOTE" + + if test -n "$rm_local" + then + rm -f "$LOCAL" + fi + if test -n "$rm_remote" + then + rm -f "$REMOTE" + fi } merge_cmd () { -- 1.8.0.rc1 ``` ## Jeremy Morton, 2012-10-27 08:47 Subject: Re: [PATCH] mergetools/p4merge: Handle "/dev/null" Message-ID: <508B9F89.7050909@game-point.net> URL: https://gitlist.dev/e/508B9F89.7050909%40game-point.net In-Reply-To: <1349925756-87801-1-git-send-email-davvid@gmail.com> ``` Sorry to be replying to this so late; I hadn't noticed the post until now! I've tried putting that code in my p4merge script and yes it does indeed work fine. However, it puts a temporary file in the working directory which I'm not sure is a good idea? If we look at this patch which actually solved pretty much the same problem, but when merging and, during a merge conflict, a file was created in both branches: https://github.com/git/git/commit/ec245ba ... it is creating a temp file in a proper temp dir, rather than in the working dir. I think that would be the proper solution here. However, I really want to get this fixed so I'd be happy for this band-aid fix of the p4merge script to be checked in until we could get a patch more like the aforementioned one, at a later date, to create empty files in a proper temp dir and pass them as $LOCAL and $REMOTE. :-) -- Best regards, Jeremy Morton (Jez) On 11/10/2012 04:22, David Aguilar wrote: > p4merge does not properly handle the case where "/dev/null" > is passed as a filename. > > Workaround it by creating a temporary file for this purpose. > > Reported-by: Jeremy Morton > Signed-off-by: David Aguilar > --- > Jeremy, can you test this? > > mergetools/p4merge | 25 +++++++++++++++++++++++++ > 1 file changed, 25 insertions(+) > > diff --git a/mergetools/p4merge b/mergetools/p4merge > index 1a45c1b..295361a 100644 > --- a/mergetools/p4merge > +++ b/mergetools/p4merge > @@ -1,5 +1,30 @@ > diff_cmd () { > + # p4merge does not like /dev/null > + rm_local= > + rm_remote= > + if test "/dev/null" = "$LOCAL" > + then > + LOCAL="./p4merge-dev-null.LOCAL.$$" > + >"$LOCAL" > + rm_local=true > + fi > + if test "/dev/null" = "$REMOTE" > + then > + REMOTE="./p4merge-dev-null.REMOTE.$$" > + >"$REMOTE" > + rm_remote=true > + fi > + > "$merge_tool_path" "$LOCAL" "$REMOTE" > + > + if test -n "$rm_local" > + then > + rm -f "$LOCAL" > + fi > + if test -n "$rm_remote" > + then > + rm -f "$REMOTE" > + fi > } > > merge_cmd () { ``` ## David Aguilar, 2012-12-20 04:41 Subject: Re: [PATCH] mergetools/p4merge: Handle "/dev/null" Message-ID: URL: https://gitlist.dev/e/CAJDDKr5rxUPzqkiNAhPpEkK4ajyPNkNsGdPYWca3oggBrWybmg%40mail.gmail.com In-Reply-To: <508B9F89.7050909@game-point.net> ``` On Sat, Oct 27, 2012 at 1:47 AM, Jeremy Morton wrote: > Sorry to be replying to this so late; I hadn't noticed the post until now! > > I've tried putting that code in my p4merge script and yes it does indeed > work fine. However, it puts a temporary file in the working directory which > I'm not sure is a good idea? If we look at this patch which actually solved > pretty much the same problem, but when merging and, during a merge conflict, > a file was created in both branches: > https://github.com/git/git/commit/ec245ba > > ... it is creating a temp file in a proper temp dir, rather than in the > working dir. I think that would be the proper solution here. However, I > really want to get this fixed so I'd be happy for this band-aid fix of the > p4merge script to be checked in until we could get a patch more like the > aforementioned one, at a later date, to create empty files in a proper temp > dir and pass them as $LOCAL and $REMOTE. :-) I had the same thoughts when I wrote it, but I figured that following the existing pattern used by mergetool for $REMOTE and $LOCAL when they do exist was simpler as the first step. I have a patch that fixes this by using mktemp that I will send shortly. It only does it for the /dev/null file since the existing behavior for files that do exist is fine. -- David ```