From a33806398a418289388ad992e385a314b4b10225 Mon Sep 17 00:00:00 2001 From: Derrick Stolee Date: Wed, 8 Sep 2021 11:23:57 +0000 Subject: merge: make sparse-aware with ORT Allow 'git merge' to operate without expanding a sparse index, at least not immediately. The index still will be expanded in a few cases: 1. If the merge strategy is 'recursive', then we enable command_requires_full_index at the start of the merge_recursive() method. We expect sparse-index users to also have the 'ort' strategy enabled. 2. With the 'ort' strategy, if the merge results in a conflicted file, then we expand the index before updating the working tree. The loop that iterates over the worktree replaces index entries and tracks 'origintal_cache_nr' which can become completely wrong if the index expands in the middle of the operation. This safety valve is important before that loop starts. A later change will focus this to only expand if we indeed have a conflict outside of the sparse-checkout cone. 3. Other merge strategies are executed as a 'git merge-X' subcommand, and those strategies are currently protected with the 'command_requires_full_index' guard. Some test updates are required, including a mistaken 'git checkout -b' that did not specify the base branch, causing merges to be fast-forward merges. Signed-off-by: Derrick Stolee Reviewed-by: Elijah Newren Signed-off-by: Junio C Hamano --- merge-recursive.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'merge-recursive.c') diff --git a/merge-recursive.c b/merge-recursive.c index 3355d50e8a..1f563cd687 100644 --- a/merge-recursive.c +++ b/merge-recursive.c @@ -3750,6 +3750,9 @@ int merge_recursive(struct merge_options *opt, assert(opt->ancestor == NULL || !strcmp(opt->ancestor, "constructed merge base")); + prepare_repo_settings(opt->repo); + opt->repo->settings.command_requires_full_index = 1; + if (merge_start(opt, repo_get_commit_tree(opt->repo, h1))) return -1; clean = merge_recursive_internal(opt, h1, h2, merge_bases, result); -- cgit v1.2.3