Re: Re* Re* [PATCH v4 0/3] advice: add "all" option to disable all hints

> So what's the conclusion of this discussion (have we reached one
> yet)?
> 
> to me it sounds like everybody is on board to raise the default used
> for format-patch.  In the old thread I said "I use something
> unreasonably high like 9999", but my "unreasonably high" number
> these days is 999, which was used in the earlier weatherbaloon
> patch.  The old thread ended with an academic "we know different
> defaults are appropriate, but what is the right number then?" but
> anything higher (like 999 or even 9999) is better than the default
> for range-diff which is 60, I would think.
> 
> Here is the patch, this time with a bit of documentation stolen from
> the old weather-balloon by Ævar.

> ----- >8 --------- >8 --------- >8 --------- >8 -----
> Subject: [PATCH] format-patch: run range-diff with larger 
> creation-factor
> 
> We see too often that a range-diff added to format-patch output
> shows too many "unmatched" patches.  This is because the default
> value for creation-factor is set to a relatively low value.
> 
> It may be justified for other uses (like you have a yet-to-be-sent
> new iteration of your series, and compare it against the 'seen'
> branch that has an older iteration, probably with the '--left-only'
> option, to pick out only your patches while ignoring the others) of
> "range-diff" command, but when the command is run as part of the
> format-patch, the user _knows_ and expects that the patches in the
> old and the new iterations roughly correspond to each other, so we
> can and should use a much higher default.
> 
> Signed-off-by: Junio C Hamano <gitster@pobox.com>
> ---
>  Documentation/git-format-patch.txt | 5 +++++
>  builtin/log.c                      | 2 +-
>  range-diff.h                       | 6 ++++++
>  3 files changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/git-format-patch.txt
> b/Documentation/git-format-patch.txt
> index 728bb3821c..b72f87b114 100644
> --- a/Documentation/git-format-patch.txt
> +++ b/Documentation/git-format-patch.txt
> @@ -346,6 +346,11 @@ material (this may change in the future).
>  	between the previous and current series of patches by adjusting the
>  	creation/deletion cost fudge factor. See linkgit:git-range-diff[1])
>  	for details.
> ++
> +Defaults to 999 (the linkgit:git-range-diff[1] uses 60), as the use
> +case is to show comparison with an older iteration of the same
> +topic and the tool should find more correspondence between the two
> +sets of patches.
> 
>  --notes[=<ref>]::
>  --no-notes::
> diff --git a/builtin/log.c b/builtin/log.c
> index c0a8bb95e9..73608ffef9 100644
> --- a/builtin/log.c
> +++ b/builtin/log.c
> @@ -2274,7 +2274,7 @@ int cmd_format_patch(int argc, const char
> **argv, const char *prefix)
>  	}
> 
>  	if (creation_factor < 0)
> -		creation_factor = RANGE_DIFF_CREATION_FACTOR_DEFAULT;
> +		creation_factor = CREATION_FACTOR_FOR_THE_SAME_SERIES;
>  	else if (!rdiff_prev)
>  		die(_("the option '%s' requires '%s'"), "--creation-factor", 
> "--range-diff");
> 
> diff --git a/range-diff.h b/range-diff.h
> index 04ffe217be..2f69f6a434 100644
> --- a/range-diff.h
> +++ b/range-diff.h
> @@ -6,6 +6,12 @@
> 
>  #define RANGE_DIFF_CREATION_FACTOR_DEFAULT 60
> 
> +/*
> + * A much higher value than the default, when we KNOW we are comparing
> + * the same series (e.g., used when format-patch calls range-diff).
> + */
> +#define CREATION_FACTOR_FOR_THE_SAME_SERIES 999
> +
>  struct range_diff_options {
>  	int creation_factor;
>  	unsigned dual_color:1;