Subject: Re: [PATCH v1 2/2] checkout: fix regression in checkout -b on intitial checkout

From: SZEDER Gábor <[email-masked]>
Date: Sat, 19 Jan 2019 01:52:02 +0100

On Fri, Jan 18, 2019 at 01:55:58PM -0500, Ben Peart wrote:
> From: Ben Peart <[email-masked]>
> 
> When doing a 'checkout -b' do a full checkout including updating the working
> tree when doing the initial checkout.  This fixes the regression in behavior
> caused by fa655d8411 checkout: optimize "git checkout -b <new_branch>"
> 
> Signed-off-by: Ben Peart <[email-masked]>
> ---
>  builtin/checkout.c         | 6 ++++++
>  t/t2018-checkout-branch.sh | 2 +-
>  2 files changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/builtin/checkout.c b/builtin/checkout.c
> index 6fadf412e8..af6b5c8336 100644
> --- a/builtin/checkout.c
> +++ b/builtin/checkout.c
> @@ -517,6 +517,12 @@ static int skip_merge_working_tree(const struct checkout_opts *opts,
>  	if (core_apply_sparse_checkout && !checkout_optimize_new_branch)
>  		return 0;
>  
> +	/*
> +	 * We must do the merge if this is the initial checkout
> +	 */
> +	if (is_cache_unborn())
> +		return 0;
> +
>  	/*
>  	 * We must do the merge if we are actually moving to a new commit.
>  	 */

This patch breaks 'checkout -b checkout.optimizeNewBranch interaction'
in 't1090-sparse-checkout-scope.sh':

  + cp .git/info/sparse-checkout .git/info/sparse-checkout.bak
  + test_when_finished
                  mv -f .git/info/sparse-checkout.bak .git/info/sparse-checkout
                  git checkout master
  
  + test 0 = 0
  + test_cleanup={
                  mv -f .git/info/sparse-checkout.bak .git/info/sparse-checkout
                  git checkout master
  
                  } && (exit "$eval_ret"); eval_ret=$?; :
  + echo /b
  + git ls-files -t b
  + test S b = S b
  + git -c checkout.optimizeNewBranch=true checkout -b fast
  Switched to a new branch 'fast'
  + git ls-files -t b
  + test H b = S b
  error: last command exited with $?=1
  not ok 4 - checkout -b checkout.optimizeNewBranch interaction