builtin/gc: add a `--detach` flag
When running `git gc --auto`, the command will by default detach and continue running in the background. This behaviour can be tweaked via the `gc.autoDetach` config, but not via a command line switch. We need that in a subsequent commit though, where git-maintenance(1) will want to ask its git-gc(1) child process to not detach anymore. Add a `--[no-]detach` flag that does this for us. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Patrick Steinhardt committed
Aug 16, 2024 at 12:45 UTC
c7185df01bb68091d3bdea2fe192f4b34e169c9d
3 files changed
+84
-36
Documentation/git-gc.txt
+4
-1
@@ -9,7 +9,7 @@ git-gc - Cleanup unnecessary files and optimize the local repository
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SYNOPSIS
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--------
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[verse]
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-'git gc' [--aggressive] [--auto] [--quiet] [--prune=<date> | --no-prune] [--force] [--keep-largest-pack]
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+'git gc' [--aggressive] [--auto] [--[no-]detach] [--quiet] [--prune=<date> | --no-prune] [--force] [--keep-largest-pack]
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DESCRIPTION
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-----------
@@ -53,6 +53,9 @@ configuration options such as `gc.auto` and `gc.autoPackLimit`, all
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other housekeeping tasks (e.g. rerere, working trees, reflog...) will
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be performed as well.
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+--[no-]detach::
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+ Run in the background if the system supports it. This option overrides
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+ the `gc.autoDetach` config.
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--[no-]cruft::
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When expiring unreachable objects, pack them separately into a
builtin/gc.c
+39
-31
@@ -242,9 +242,13 @@ static enum schedule_priority parse_schedule(const char *value)
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struct maintenance_run_opts {
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int auto_flag;
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+ int detach;
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int quiet;
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enum schedule_priority schedule;
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};
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+#define MAINTENANCE_RUN_OPTS_INIT { \
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+ .detach = -1, \
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+}
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static int pack_refs_condition(UNUSED struct gc_config *cfg)
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{
@@ -664,7 +668,7 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
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int keep_largest_pack = -1;
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timestamp_t dummy;
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struct child_process rerere_cmd = CHILD_PROCESS_INIT;
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- struct maintenance_run_opts opts = {0};
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+ struct maintenance_run_opts opts = MAINTENANCE_RUN_OPTS_INIT;
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struct gc_config cfg = GC_CONFIG_INIT;
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const char *prune_expire_sentinel = "sentinel";
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const char *prune_expire_arg = prune_expire_sentinel;
@@ -681,6 +685,8 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
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OPT_BOOL(0, "aggressive", &aggressive, N_("be more thorough (increased runtime)")),
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OPT_BOOL_F(0, "auto", &opts.auto_flag, N_("enable auto-gc mode"),
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PARSE_OPT_NOCOMPLETE),
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+ OPT_BOOL(0, "detach", &opts.detach,
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+ N_("perform garbage collection in the background")),
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OPT_BOOL_F(0, "force", &force,
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N_("force running gc even if there may be another gc running"),
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PARSE_OPT_NOCOMPLETE),
@@ -729,6 +735,9 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
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strvec_push(&repack, "-q");
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if (opts.auto_flag) {
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+ if (cfg.detach_auto && opts.detach < 0)
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+ opts.detach = 1;
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+
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/*
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* Auto-gc should be least intrusive as possible.
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*/
@@ -738,38 +747,12 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
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}
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if (!quiet) {
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- if (cfg.detach_auto)
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+ if (opts.detach > 0)
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fprintf(stderr, _("Auto packing the repository in background for optimum performance.\n"));
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else
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fprintf(stderr, _("Auto packing the repository for optimum performance.\n"));
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fprintf(stderr, _("See \"git help gc\" for manual housekeeping.\n"));
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}
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- if (cfg.detach_auto) {
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- ret = report_last_gc_error();
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- if (ret == 1) {
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- /* Last gc --auto failed. Skip this one. */
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- ret = 0;
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- goto out;
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-
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- } else if (ret) {
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- /* an I/O error occurred, already reported */
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- goto out;
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- }
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-
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- if (lock_repo_for_gc(force, &pid)) {
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- ret = 0;
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- goto out;
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- }
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-
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- gc_before_repack(&opts, &cfg); /* dies on failure */
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- delete_tempfile(&pidfile);
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-
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- /*
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- * failure to daemonize is ok, we'll continue
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- * in foreground
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- */
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- daemonized = !daemonize();
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- }
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} else {
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struct string_list keep_pack = STRING_LIST_INIT_NODUP;
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@@ -784,6 +767,33 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
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string_list_clear(&keep_pack, 0);
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}
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+ if (opts.detach > 0) {
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+ ret = report_last_gc_error();
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+ if (ret == 1) {
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+ /* Last gc --auto failed. Skip this one. */
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+ ret = 0;
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+ goto out;
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+
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+ } else if (ret) {
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+ /* an I/O error occurred, already reported */
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+ goto out;
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+ }
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+
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+ if (lock_repo_for_gc(force, &pid)) {
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+ ret = 0;
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+ goto out;
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+ }
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+
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+ gc_before_repack(&opts, &cfg); /* dies on failure */
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+ delete_tempfile(&pidfile);
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+
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+ /*
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+ * failure to daemonize is ok, we'll continue
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+ * in foreground
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+ */
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+ daemonized = !daemonize();
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+ }
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+
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name = lock_repo_for_gc(force, &pid);
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if (name) {
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if (opts.auto_flag) {
@@ -1537,7 +1547,7 @@ static int task_option_parse(const struct option *opt UNUSED,
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static int maintenance_run(int argc, const char **argv, const char *prefix)
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{
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int i;
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- struct maintenance_run_opts opts;
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+ struct maintenance_run_opts opts = MAINTENANCE_RUN_OPTS_INIT;
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struct gc_config cfg = GC_CONFIG_INIT;
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struct option builtin_maintenance_run_options[] = {
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OPT_BOOL(0, "auto", &opts.auto_flag,
@@ -1554,8 +1564,6 @@ static int maintenance_run(int argc, const char **argv, const char *prefix)
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};
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int ret;
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- memset(&opts, 0, sizeof(opts));
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-
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opts.quiet = !isatty(2);
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for (i = 0; i < TASK__COUNT; i++)
t/t6500-gc.sh
+41
-4
@@ -338,14 +338,14 @@ test_expect_success 'gc.maxCruftSize sets appropriate repack options' '
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test_subcommand $cruft_max_size_opts --max-cruft-size=3145728 <trace2.txt
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'
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-run_and_wait_for_auto_gc () {
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+run_and_wait_for_gc () {
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# We read stdout from gc for the side effect of waiting until the
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# background gc process exits, closing its fd 9. Furthermore, the
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# variable assignment from a command substitution preserves the
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# exit status of the main gc process.
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# Note: this fd trickery doesn't work on Windows, but there is no
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# need to, because on Win the auto gc always runs in the foreground.
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- doesnt_matter=$(git gc --auto 9>&1)
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+ doesnt_matter=$(git gc "$@" 9>&1)
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}
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test_expect_success 'background auto gc does not run if gc.log is present and recent but does if it is old' '
@@ -361,7 +361,7 @@ test_expect_success 'background auto gc does not run if gc.log is present and re
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test-tool chmtime =-345600 .git/gc.log &&
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git gc --auto &&
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test_config gc.logexpiry 2.days &&
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- run_and_wait_for_auto_gc &&
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+ run_and_wait_for_gc --auto &&
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ls .git/objects/pack/pack-*.pack >packs &&
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test_line_count = 1 packs
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'
@@ -391,11 +391,48 @@ test_expect_success 'background auto gc respects lock for all operations' '
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printf "%d %s" "$shell_pid" "$hostname" >.git/gc.pid &&
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# our gc should exit zero without doing anything
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- run_and_wait_for_auto_gc &&
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+ run_and_wait_for_gc --auto &&
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(ls -1 .git/refs/heads .git/reftable >actual || true) &&
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test_cmp expect actual
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'
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+test_expect_success '--detach overrides gc.autoDetach=false' '
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+ test_when_finished "rm -rf repo" &&
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+ git init repo &&
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+ (
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+ cd repo &&
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+
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+ # Prepare the repository such that git-gc(1) ends up repacking.
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+ test_commit "$(test_oid blob17_1)" &&
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+ test_commit "$(test_oid blob17_2)" &&
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+ git config gc.autodetach false &&
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+ git config gc.auto 2 &&
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+
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+ # Note that we cannot use `test_cmp` here to compare stderr
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+ # because it may contain output from `set -x`.
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+ run_and_wait_for_gc --auto --detach 2>actual &&
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+ test_grep "Auto packing the repository in background for optimum performance." actual
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+ )
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+'
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+
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+test_expect_success '--no-detach overrides gc.autoDetach=true' '
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+ test_when_finished "rm -rf repo" &&
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+ git init repo &&
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+ (
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+ cd repo &&
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+
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+ # Prepare the repository such that git-gc(1) ends up repacking.
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+ test_commit "$(test_oid blob17_1)" &&
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+ test_commit "$(test_oid blob17_2)" &&
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+ git config gc.autodetach true &&
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+ git config gc.auto 2 &&
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+
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+ GIT_PROGRESS_DELAY=0 git gc --auto --no-detach 2>output &&
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+ test_grep "Auto packing the repository for optimum performance." output &&
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+ test_grep "Collecting referenced commits: 2, done." output
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+ )
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+'
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+
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# DO NOT leave a detached auto gc process running near the end of the
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# test script: it can run long enough in the background to racily
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# interfere with the cleanup in 'test_done'.