Re: [PATCH] git-submodule.sh: try harder to fetch a submodule

From: Jonathan Nieder <jrnieder@gmail.com>
Date: May 11, 2018, 23:28 UTC
Message-ID: <20180511232840.GB41222@aiede.svl.corp.google.com>
In-Reply-To: <20180511231751.162855-1-sbeller@google.com>

Hi,

Stefan Beller wrote:

> This is the logical continuum of fb43e31f2b4 (submodule: try harder to
> fetch needed sha1 by direct fetching sha1, 2016-02-23) and fixes it as
> some assumptions were not correct.

Interesting.

I think what would help most is an example set of commands I can use to reproduce this (bonus points if in the form of a test).

> > If $sha1 was not part of the default fetch ... fail ourselves here
> assumes that the fetch_in_submodule only fails when the serverside does

I'm having some trouble with the formatting here. Is the part preceded by '>' a quote, and if so a quote from what?

Show 5 quoted lines

> not support fetching by sha1.
>
> There are other failures, why such a fetch may fail, such as
>     fatal: Couldn't find remote ref HEAD
> which can happen if the remote side doesn't advertise HEAD. Not advertising

nit: it can be useful to have a blank line before and after such example output to help both my eyes and tools like "git log --format='%w(100)%b'" to understand the formatting.

> HEAD is allowed by the protocol spec and would happen, if HEAD points at a
> ref, that this user cannot see (due to ACLs for example).

A more typical example would be if the ref simply doesn't exist (i.e., is a branch yet to be born).

Show 17 quoted lines

> So do try even harder for a submodule by ignoring the exit code of the
> first fetch and rather relying on the following is_tip_reachable to
> see if we try fetching again.
>
> Signed-off-by: Stefan Beller <sbeller@google.com>
> ---
>  git-submodule.sh | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/git-submodule.sh b/git-submodule.sh
> index 24914963ca2..13b378a6c8f 100755
> --- a/git-submodule.sh
> +++ b/git-submodule.sh
> @@ -614,7 +614,6 @@ cmd_update()
>  				# is not reachable from a ref.
>  				is_tip_reachable "$sm_path" "$sha1" ||
>  				fetch_in_submodule "$sm_path" $depth ||

Is keeping the '||' at the end of this line intended?

Show 7 quoted lines

> -				die "$(eval_gettext "Unable to fetch in submodule path '\$displaypath'")"
>  
>  				# Now we tried the usual fetch, but $sha1 may
>  				# not be reachable from any of the refs
> 				is_tip_reachable "$sm_path" "$sha1" ||
> 				fetch_in_submodule "$sm_path" $depth "$sha1" ||
> 				die "$(eval_gettext "Fetched in submodule path '\$displaypath', but it did not contain \$sha1. Direct fetching of that commit failed.")"

Should this error message be changed?

Thanks, Jonathan