Proposal: discourage packagers from enabling merge-tool configs

[Ryan McElroy]

On 3/11/2015 9:05 AM, Harvey Chapman wrote:
>> On Mar 11, 2015, at 11:53 AM, Augie Fackler <raf at durin42.com> wrote:
>>
>>
>> On Mar 11, 2015, at 11:48 AM, Mads Kiilerich <mads at kiilerich.com> wrote:
>>
>>> On 03/11/2015 04:38 PM, Augie Fackler wrote:
>>>> On Mar 11, 2015, at 11:36 AM, Mads Kiilerich <mads at kiilerich.com> wrote:
>>>>
>>>>> On 03/11/2015 04:32 PM, Augie Fackler wrote:
>>>>>> On Mar 11, 2015, at 11:29 AM, Mads Kiilerich <mads at kiilerich.com> wrote:
>>>>>>
>>>>> Yes, I said I agreed that we shouldn't fall back to gvimdiff but have some other option with higher precedence. Where do we disagree?
>>>> If gvimdiff is the only merge-tool on my system, I still never ever want to see it, and I suspect this is true of the vast majority of people that don't understand how to use gvimdiff. If I understand your position, you want merge-tools enabled by default, whereas I want them *all* off by default, but with easy examples of how to enable the sensible ones. I'm happy to compromise somewhere if we can come up with a list of merge tools that aren't abstruse to escape if you end up in them unintentionally.
>>> Why do you not want the good and "probably intentionally installed" merge tools to be detected automatically?
>> If we can detect when a user has intentionally installed something (rather than it being installed by default as part of a company's base image or the developer-tools metapackage or something), that's fine with me. I'm not aware of anything like that though, so my proposal is to give up.
>>
>> I can live with it if we do something like disable gvimdiff and its other hard-to-use non-GUI kin. But that seems a little odd, since now some merge tools are special and others aren't.
>>
>> I don't really know why users expect their merge tool to "just work" with Mercurial - that's literally never happened for me with any VCS, why do they expect it with hg?
>>
> FWIW My biggest problem with vimdiff is that the last time I checked google, 3-way merging with vimdiff is completely undocumented. Two-way information can be found, but it always speaks about commands in terms of the “other” window (singular).

Kinda-related: 
http://arcanius.silverfir.net/blog/make-mercurial-use-vimdiff-the-same-way-git-does/

It would be cool if no mergetool dropped information by default.

Overall, I'm on the same page as Augie: do the safe, generic thing by 
default. People who want more advanced tools will figure out how to set 
those up (and we can provide great online guides).