gc: fix handling of crontab magic markers

On `git maintenance start`, we add a few entries to the user's cron
table. We wrap our entries using two magic markers, "# BEGIN GIT
MAINTENANCE SCHEDULE" and "# END GIT MAINTENANCE SCHEDULE". At a later
`git maintenance stop`, we will go through the table and remove these
lines. Or rather, we will remove the "BEGIN" marker, the "END" marker
and everything between them.

Alas, we have a bug in how we detect the "END" marker: we don't. As we
loop through all the lines of the crontab, if we are in the "old
region", i.e., the region we're aiming to remove, we make an early
`continue` and don't get as far as checking for the "END" marker. Thus,
once we've seen our "BEGIN", we remove everything until the end of the
file.

Rewrite the logic for identifying these markers. There are four cases
that are mutually exclusive: The current line starts a region or it ends
it, or it's firmly within the region, or it's outside of it (and should
be printed).

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Acked-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/gc.c b/builtin/gc.c
index b57fda49240ecae6beb9889711169e5a6590e3af..4c24f418520a6072ccea8fcd101643f735ac5e9d 100644 (file)
--- a/builtin/gc.c
+++ b/builtin/gc.c
@@ -1554,11 +1554,10 @@ static int update_background_schedule(int run_maintenance)
        while (!strbuf_getline_lf(&line, cron_list)) {
                if (!in_old_region && !strcmp(line.buf, BEGIN_LINE))
                        in_old_region = 1;
-               if (in_old_region)
-                       continue;
-               fprintf(cron_in, "%s\n", line.buf);
-               if (in_old_region && !strcmp(line.buf, END_LINE))
+               else if (in_old_region && !strcmp(line.buf, END_LINE))
                        in_old_region = 0;
+               else if (!in_old_region)
+                       fprintf(cron_in, "%s\n", line.buf);
        }
 
        if (run_maintenance) {

diff --git a/t/t7900-maintenance.sh b/t/t7900-maintenance.sh
index d1e0c8f8301d12b28130ecc747f0d3cf44ba7034..4bbfce31e95e80d50de638beb9605dffa9cdc630 100755 (executable)
--- a/t/t7900-maintenance.sh
+++ b/t/t7900-maintenance.sh
@@ -446,6 +446,13 @@ test_expect_success 'start preserves existing schedule' '
        grep "Important information!" cron.txt
 '
 
+test_expect_success 'stop preserves surrounding schedule' '
+       echo "Crucial information!" >>cron.txt &&
+       GIT_TEST_CRONTAB="test-tool crontab cron.txt" git maintenance stop &&
+       grep "Important information!" cron.txt &&
+       grep "Crucial information!" cron.txt
+'
+
 test_expect_success 'register preserves existing strategy' '
        git config maintenance.strategy none &&
        git maintenance register &&