Subject: Re: [PATCH v6] notes: handle multiple worktrees

From: David Turner <[email-masked]>
Date: Mon, 10 Aug 2015 13:48:33 -0400

Sorry, that should have included the first patch as well.  Will re-send
as .v7

On Mon, 2015-08-10 at 13:43 -0400, David Turner wrote:
> Before creating NOTES_MERGE_REF, check NOTES_MERGE_REF using
> find_shared_symref and die if we find one.  This prevents simultaneous
> merges to the same notes branch from different worktrees.
> 
> Signed-off-by: David Turner <[email-masked]>
> ---
> 
> This reroll addresses Eric Sunshine's comments on v5.
> 
> ---
>  builtin/notes.c                  |  6 ++++
>  t/t3320-notes-merge-worktrees.sh | 72 ++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 78 insertions(+)
>  create mode 100755 t/t3320-notes-merge-worktrees.sh
> 
> diff --git a/builtin/notes.c b/builtin/notes.c
> index 63f95fc..0423480 100644
> --- a/builtin/notes.c
> +++ b/builtin/notes.c
> @@ -19,6 +19,7 @@
>  #include "string-list.h"
>  #include "notes-merge.h"
>  #include "notes-utils.h"
> +#include "branch.h"
>  
>  static const char * const git_notes_usage[] = {
>  	N_("git notes [--ref <notes-ref>] [list [<object>]]"),
> @@ -825,10 +826,15 @@ static int merge(int argc, const char **argv, const char *prefix)
>  		update_ref(msg.buf, default_notes_ref(), result_sha1, NULL,
>  			   0, UPDATE_REFS_DIE_ON_ERR);
>  	else { /* Merge has unresolved conflicts */
> +		char *existing;
>  		/* Update .git/NOTES_MERGE_PARTIAL with partial merge result */
>  		update_ref(msg.buf, "NOTES_MERGE_PARTIAL", result_sha1, NULL,
>  			   0, UPDATE_REFS_DIE_ON_ERR);
>  		/* Store ref-to-be-updated into .git/NOTES_MERGE_REF */
> +		existing = find_shared_symref("NOTES_MERGE_REF", default_notes_ref());
> +		if (existing)
> +			die(_("A notes merge into %s is already in-progress at %s"),
> +			    default_notes_ref(), existing);
>  		if (create_symref("NOTES_MERGE_REF", default_notes_ref(), NULL))
>  			die("Failed to store link to current notes ref (%s)",
>  			    default_notes_ref());
> diff --git a/t/t3320-notes-merge-worktrees.sh b/t/t3320-notes-merge-worktrees.sh
> new file mode 100755
> index 0000000..a7beef2
> --- /dev/null
> +++ b/t/t3320-notes-merge-worktrees.sh
> @@ -0,0 +1,72 @@
> +#!/bin/sh
> +#
> +# Copyright (c) 2015 Twitter, Inc
> +#
> +
> +test_description='Test merging of notes trees in multiple worktrees'
> +
> +. ./test-lib.sh
> +
> +test_expect_success 'setup commit' '
> +	test_commit tantrum
> +'
> +
> +commit_tantrum=$(git rev-parse tantrum^{commit})
> +
> +test_expect_success 'setup notes ref (x)' '
> +	git config core.notesRef refs/notes/x &&
> +	git notes add -m "x notes on tantrum" tantrum
> +'
> +
> +test_expect_success 'setup local branch (y)' '
> +	git update-ref refs/notes/y refs/notes/x &&
> +	git config core.notesRef refs/notes/y &&
> +	git notes remove tantrum
> +'
> +
> +test_expect_success 'setup remote branch (z)' '
> +	git update-ref refs/notes/z refs/notes/x &&
> +	git config core.notesRef refs/notes/z &&
> +	git notes add -f -m "conflicting notes on tantrum" tantrum
> +'
> +
> +test_expect_success 'modify notes ref ourselves (x)' '
> +	git config core.notesRef refs/notes/x &&
> +	git notes add -f -m "more conflicting notes on tantrum" tantrum
> +'
> +
> +test_expect_success 'create some new worktrees' '
> +	git worktree add -b newbranch worktree master &&
> +	git worktree add -b newbranch2 worktree2 master
> +'
> +
> +test_expect_success 'merge z into y fails and sets NOTES_MERGE_REF' '
> +	git config core.notesRef refs/notes/y &&
> +	test_must_fail git notes merge z &&
> +	echo "ref: refs/notes/y" > expect &&
> +	test_cmp .git/NOTES_MERGE_REF expect
> +'
> +
> +test_expect_success 'merge z into y while mid-merge in another workdir fails' '
> +	(
> +		cd worktree &&
> +		git config core.notesRef refs/notes/y &&
> +		test_must_fail git notes merge z 2>err &&
> +		grep "A notes merge into refs/notes/y is already in-progress at" err
> +	) &&
> +	test_path_is_missing .git/worktrees/worktree/NOTES_MERGE_REF
> +'
> +
> +test_expect_success 'merge z into x while mid-merge on y succeeds' '
> +	(
> +		cd worktree2 &&
> +		git config core.notesRef refs/notes/x &&
> +		test_must_fail git notes merge z 2>&1 >out &&
> +		grep "Automatic notes merge failed" out &&
> +		grep -v "A notes merge into refs/notes/x is already in-progress in" out
> +	) &&
> +	echo "ref: refs/notes/x" > expect &&
> +	test_cmp .git/worktrees/worktree2/NOTES_MERGE_REF expect
> +'
> +
> +test_done