Re: [PATCH 07/14] update submodules: introduce is_interesting_submodule

[Stefan Beller <sbeller@google.com>]

On Wed, Feb 15, 2017 at 9:04 AM, Brandon Williams <bmwill@google.com> wrote:
> On 02/14, Stefan Beller wrote:
>> In later patches we introduce the --recurse-submodule flag for commands
>> that modify the working directory, e.g. git-checkout.
>>
>> It is potentially expensive to check if a submodule needs an update,
>> because a common theme to interact with submodules is to spawn a child
>> process for each interaction.
>>
>> So let's introduce a function that pre checks if a submodule needs
>> to be checked for an update.
>>
>> Signed-off-by: Stefan Beller <sbeller@google.com>
>> ---
>>  submodule.c | 26 ++++++++++++++++++++++++++
>>  submodule.h |  8 ++++++++
>>  2 files changed, 34 insertions(+)
>>
>> diff --git a/submodule.c b/submodule.c
>> index c0060c29f2..4c33374ae8 100644
>> --- a/submodule.c
>> +++ b/submodule.c
>> @@ -551,6 +551,32 @@ void set_config_update_recurse_submodules(int value)
>>       config_update_recurse_submodules = value;
>>  }
>>
>> +int submodules_interesting_for_update(void)
>> +{
>> +     /*
>> +      * Update can't be "none", "merge" or "rebase",
>> +      * treat any value as OFF, except an explicit ON.
>> +      */
>> +     return config_update_recurse_submodules == RECURSE_SUBMODULES_ON;
>> +}
>> +
>> +int is_interesting_submodule(const struct cache_entry *ce)
>
> Is there perhaps a more descriptive function name we could use instead
> of "is_interesting"?  The problem is that its difficult to know why its
> interesting or for what purpose it is interesting.

I should finish the background story patch first. By 'is_interesting' I mean
* it is active/initialized/"The user expressed interested in the submodule by
  setting submodule.<name>.URL
* its submodule.<name>.update strategy is != NONE.

The second point is interesting, as that entertains the thought that we'll pay
attention to the submodule.<name>.update strategy at all and
we may want to also implement rebase/merge eventually.

So I think we'd want to tighten that down to "checkout" only for now.

Thanks,
Stefan