[PATCH v2] index-pack: clarify the breached limit

From: Matt Cooper <vtbassmatt@gmail.com>

As a small courtesy to users, report what limit was breached. This is especially useful when a push exceeds a server-defined limit, since the user is unlikely to have configured the limit (their host did). Also demonstrate the human-readable message in a test.

Helped-by: Taylor Blau <me@ttaylorr.com>
Helped-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Matt Cooper <vtbassmatt@gmail.com>
---
    Specify the actual pack size limit which is breached
    
    Git allows configuring a maximum pack size. GitHub (like presumably
    other Git hosts) configures this setting to a generous but finite limit.
    When a user attempts to push an oversized pack, their connection is
    terminated with a message that they've exceeded the limit. The user has
    to find the limit value elsewhere, probably in the host's documentation.
    This change adds a small convenience -- specifying the limit itself in
    the error message -- so that users no longer have to search elsewhere to
    discover the limit.
    
    v2 squashes the changes into one commit and corrects the commit trailer
    misordering.

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1158%2Fvtbassmatt%2Fmc%2Fhumanize-limit-v2
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1158/vtbassmatt/mc/humanize-limit-v2
Pull-Request: https://github.com/gitgitgadget/git/pull/1158

Range-diff vs v1:

 1:  a2eb3956f3e ! 1:  abf21ec109a index-pack: clarify the breached limit
     @@ Commit message
          As a small courtesy to users, report what limit was breached. This
          is especially useful when a push exceeds a server-defined limit, since
          the user is unlikely to have configured the limit (their host did).
     +    Also demonstrate the human-readable message in a test.
      
     +    Helped-by: Taylor Blau <me@ttaylorr.com>
     +    Helped-by: Derrick Stolee <derrickstolee@github.com>
          Signed-off-by: Matt Cooper <vtbassmatt@gmail.com>
      
       ## builtin/index-pack.c ##
     @@ builtin/index-pack.c: static void use(int bytes)
       }
       
       static const char *open_pack_file(const char *pack_name)
     +
     + ## t/t5302-pack-index.sh ##
     +@@ t/t5302-pack-index.sh: test_expect_success 'index-pack -v --stdin produces progress for both phases' '
     + 	test_i18ngrep "Resolving deltas" err
     + '
     + 
     ++test_expect_success 'too-large packs report the breach' '
     ++	pack=$(git pack-objects --all pack </dev/null) &&
     ++	sz="$(test_file_size pack-$pack.pack)" &&
     ++	test "$sz" -gt 20 &&
     ++	test_must_fail git index-pack --max-input-size=20 pack-$pack.pack 2>err &&
     ++	grep "maximum allowed size (20 bytes)" err
     ++'
     ++
     + test_done
 2:  43990408a10 < -:  ----------- t5302: confirm that large packs mention limit

 builtin/index-pack.c  | 8 ++++++--
 t/t5302-pack-index.sh | 8 ++++++++
 2 files changed, 14 insertions(+), 2 deletions(-)