[PATCH v2 00/18] Improve handling of D/F conflicts

This is a re-roll of [1]. This patch series improves the handling of conflicts between references like "refs/foo" and "refs/foo/bar" that are not allowed to co-exist. It also changes some functions in this area to record their error messages in a "struct strbuf *err" argument rather than sometimes emitting errors directly to stderr.

Changes relative to v1:

* Rebase to master rather than depending on
  mh/ref-lock-avoid-running-out-of-fds, as did v1. There were no
  significant dependencies between the two patch series, and now that
  mh/ref-lock-avoid-running-out-of-fds (now renamed to
  mh/write-refs-sooner.*) has been backported to 2.2, the dependency
  makes even less sense.

* Fix leak of "reason" string in ref_transaction_commit().

* Fix a broken &&-chain in t1404 and fix the function definition as
  per Junio's "SQUASH???" commit.

Thanks to Stefan, Junio, and Eric for their comments regarding v1.

As usual, this patch series is also available from my GitHub repository [2], as branch "check-df-conflicts-earlier".

Michael

[1] http://thread.gmane.org/gmane.comp.version-control.git/268117 [2] https://github.com/mhagger/git

Michael Haggerty (18):
  t1404: new tests of ref D/F conflicts within transactions
  is_refname_available(): revamp the comments
  is_refname_available(): avoid shadowing "dir" variable
  is_refname_available(): convert local variable "dirname" to strbuf
  entry_matches(): inline function
  report_refname_conflict(): inline function
  struct nonmatching_ref_data: store a refname instead of a ref_entry
  is_refname_available(): use dirname in first loop
  ref_transaction_commit(): use a string_list for detecting duplicates
  refs: check for D/F conflicts among refs created in a transaction
  verify_refname_available(): rename function
  verify_refname_available(): report errors via a "struct strbuf *err"
  lock_ref_sha1_basic(): report errors via a "struct strbuf *err"
  lock_ref_sha1_basic(): improve diagnostics for ref D/F conflicts
  rename_ref(): integrate lock_ref_sha1_basic() errors into ours
  ref_transaction_commit(): provide better error messages
  ref_transaction_commit(): delete extra "the" from error message
  reflog_expire(): integrate lock_ref_sha1_basic() errors into ours

 refs.c                             | 309 ++++++++++++++++++++++++-------------
 t/t1400-update-ref.sh              |  14 +-
 t/t1404-update-ref-df-conflicts.sh | 107 +++++++++++++
 3 files changed, 312 insertions(+), 118 deletions(-)
 create mode 100755 t/t1404-update-ref-df-conflicts.sh