diff-files: integrate with sparse index

Remove full index requirement for `git diff-files`. Refactor the
ensure_expanded and ensure_not_expanded functions by introducing a
common helper function, ensure_index_state. Add test to ensure the index
is no expanded in `git diff-files`.

The `p2000` tests demonstrate a ~96% execution time reduction for 'git
diff-files' and a ~97% execution time reduction for 'git diff-files'
for a file using a sparse index:

Test                                               before  after
-----------------------------------------------------------------------
2000.94: git diff-files (full-v3)                  0.09    0.08 -11.1%
2000.95: git diff-files (full-v4)                  0.09    0.09 +0.0%
2000.96: git diff-files (sparse-v3)                0.52    0.02 -96.2%
2000.97: git diff-files (sparse-v4)                0.51    0.02 -96.1%
2000.98: git diff-files -- f2/f4/a (full-v3)       0.06    0.07 +16.7%
2000.99: git diff-files -- f2/f4/a (full-v4)       0.08    0.08 +0.0%
2000.100: git diff-files -- f2/f4/a (sparse-v3)    0.46    0.01 -97.8%
2000.101: git diff-files -- f2/f4/a (sparse-v4)    0.51    0.02 -96.1%

Signed-off-by: Shuqi Liang <cheskaqiqi@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/diff-files.c b/builtin/diff-files.c
index dc991f753bb8f10b2414a9c3486f8374d388f82a..360464e6ef2dc4a2a613c4e8f8a59e2237a7d327 100644 (file)
--- a/builtin/diff-files.c
+++ b/builtin/diff-files.c
@@ -27,6 +27,10 @@ int cmd_diff_files(int argc, const char **argv, const char *prefix)
                usage(diff_files_usage);
 
        git_config(git_diff_basic_config, NULL); /* no "diff" UI options */
+
+       prepare_repo_settings(the_repository);
+       the_repository->settings.command_requires_full_index = 0;
+
        repo_init_revisions(the_repository, &rev, prefix);
        rev.abbrev = 0;
 

diff --git a/t/perf/p2000-sparse-operations.sh b/t/perf/p2000-sparse-operations.sh
index 60d1de0662ac4842f0163d05366b20a62524f3db..901cc493ef19e10941ca93a920344f4ff52a59ca 100755 (executable)
--- a/t/perf/p2000-sparse-operations.sh
+++ b/t/perf/p2000-sparse-operations.sh
@@ -129,5 +129,7 @@ test_perf_on_all git grep --cached bogus -- "f2/f1/f1/*"
 test_perf_on_all git write-tree
 test_perf_on_all git describe --dirty
 test_perf_on_all 'echo >>new && git describe --dirty'
+test_perf_on_all git diff-files
+test_perf_on_all git diff-files -- $SPARSE_CONE/a
 
 test_done

diff --git a/t/t1092-sparse-checkout-compatibility.sh b/t/t1092-sparse-checkout-compatibility.sh
index b06b5220306b2afff5cd3fcca3ae7d88e0fa941e..e58bfbfcb4f385b9b9c672ca24ab605c59d627da 100755 (executable)
--- a/t/t1092-sparse-checkout-compatibility.sh
+++ b/t/t1092-sparse-checkout-compatibility.sh
@@ -1377,7 +1377,7 @@ test_expect_success 'index.sparse disabled inline uses full index' '
        ! test_region index ensure_full_index trace2.txt
 '
 
-ensure_not_expanded () {
+run_sparse_index_trace2 () {
        rm -f trace2.txt &&
        if test -z "$WITHOUT_UNTRACKED_TXT"
        then
@@ -1397,7 +1397,16 @@ ensure_not_expanded () {
                        git -C sparse-index "$@" \
                        >sparse-index-out \
                        2>sparse-index-error || return 1
-       fi &&
+       fi
+}
+
+ensure_expanded () {
+       run_sparse_index_trace2 "$@" &&
+       test_region index ensure_full_index trace2.txt
+}
+
+ensure_not_expanded () {
+       run_sparse_index_trace2 "$@" &&
        test_region ! index ensure_full_index trace2.txt
 }
 
@@ -2147,4 +2156,18 @@ test_expect_success 'diff-files with pathspec outside sparse definition' '
        test_all_match git diff-files -- "folder*/a"
 '
 
+test_expect_success 'sparse index is not expanded: diff-files' '
+       init_repos &&
+
+       write_script edit-contents <<-\EOF &&
+       echo text >>"$1"
+       EOF
+
+       run_on_all ../edit-contents deep/a &&
+
+       ensure_not_expanded diff-files &&
+       ensure_not_expanded diff-files -- deep/a &&
+       ensure_not_expanded diff-files -- "deep/*"
+'
+
 test_done