Re: [RFC PATCH v3 3/8] Read .gitignore from index if it is assume-unchanged

[Nguyen Thai Ngoc Duy <pclouds@gmail.com>]

2009/8/12 Junio C Hamano <gitster@pobox.com>:
> Nguyễn Thái Ngọc Duy  <pclouds@gmail.com> writes:
>
>> diff --git a/Documentation/technical/api-directory-listing.txt b/Documentation/technical/api-directory-listing.txt
>> index 5bbd18f..7d0e282 100644
>> --- a/Documentation/technical/api-directory-listing.txt
>> +++ b/Documentation/technical/api-directory-listing.txt
>> @@ -58,6 +58,9 @@ The result of the enumeration is left in these fields::
>>  Calling sequence
>>  ----------------
>>
>> +* Ensure the_index is populated as it may have CE_VALID entries that
>> +  affect directory listing.
>> +
>
> When you want to enumerate all paths in the work tree, instead of not just
> the untracked ones, it used to be possible to first run read_directory()
> before calling read_cache().  You are now forbidding this.

Either I phrased it badly, or I don't follow you. If you don't call
read_cache() before read_directory(), the_index should be empty and
read_assume_unchanged_from_index() will be no-op. So read_directory()
behavior does not change in this case.

> I do not think it is hard to resurrect the feature if it is necessary (add
> an option to dir_struct and teach dir_add_name() not to ignore paths the
> index knows about), and I do not think none of the existing code relies on
> it anymore (I think "git add" used to), but there may be some codepath I
> forgot about, which is a concern.

Hmm.. "git add" loaded index early since the first version of
builtin-add.c. I have checked all code path that can lead to
read_directory_recursively(). In all cases, index is loaded before
read_dir..() is called.

>> diff --git a/builtin-clean.c b/builtin-clean.c
>> index 2d8c735..d917472 100644
>> --- a/builtin-clean.c
>> +++ b/builtin-clean.c
>> @@ -71,8 +71,11 @@ int cmd_clean(int argc, const char **argv, const char *prefix)
>>
>>       dir.flags |= DIR_SHOW_OTHER_DIRECTORIES;
>>
>> -     if (!ignored)
>> +     if (!ignored) {
>> +             if (read_cache() < 0)
>> +                     die("index file corrupt");
>>               setup_standard_excludes(&dir);
>> +     }
>>
>>       pathspec = get_pathspec(prefix, argv);
>>       read_cache();
>
> Wouldn't it be much cleaner to move the existing read_cache() up, like you
> did for ls-files, instead of conditionally reading the index at a random
> place in the program sequence depending on the combinations of options?

Agreed. read_cache() is called right below anyway.
-- 
Duy