[PATCH] parse-datetime: support 'J' military time zone

[Paul Eggert]

Requested by Brian Inglis in:
https://savannah.gnu.org/support/?110644
* lib/parse-datetime.y (parser_control): New member J_zones_seen.
(item): New item 'J'.
(military_table): Add 'J'.
(parse_datetime_body): Set and use J_zones_seen.
* tests/test-parse-datetime.c (main): Test "J".
---
 ChangeLog                   | 11 +++++++++++
 doc/parse-datetime.texi     |  2 +-
 lib/parse-datetime.y        | 15 ++++++++++++---
 tests/test-parse-datetime.c | 10 ++++++++++
 4 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 3b1f715527..d86cf0048b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2022-05-17  Paul Eggert  <eggert@cs.ucla.edu>
+
+       parse-datetime: support 'J' military time zone
+       Requested by Brian Inglis in:
+       https://savannah.gnu.org/support/?110644
+       * lib/parse-datetime.y (parser_control): New member J_zones_seen.
+       (item): New item 'J'.
+       (military_table): Add 'J'.
+       (parse_datetime_body): Set and use J_zones_seen.
+       * tests/test-parse-datetime.c (main): Test "J".
+
 2022-05-15  Reuben Thomas  <rrt@sc3d.org>
 
        doc: Update regex documentation to match implementation.
diff --git a/doc/parse-datetime.texi b/doc/parse-datetime.texi
index 575b4d5aea..44305d136c 100644
--- a/doc/parse-datetime.texi
+++ b/doc/parse-datetime.texi
@@ -304,7 +304,7 @@ Time zone items other than @samp{UTC} and @samp{Z}
 are obsolescent and are not recommended, because they
 are ambiguous; for example, @samp{EST} has a different meaning in
 Australia than in the United States, and @samp{A} has different
-meaning as a military time zone than as an obsolescent
+meaning as a military time zone than as an obsolete
 RFC 822 time zone.  Instead, it's better to use
 unambiguous numeric time zone corrections like @samp{-0500}, as
 described in the previous section.
diff --git a/lib/parse-datetime.y b/lib/parse-datetime.y
index 7220d05dd7..0903c2003e 100644
--- a/lib/parse-datetime.y
+++ b/lib/parse-datetime.y
@@ -205,6 +205,7 @@ typedef struct
   bool rels_seen;
   idx_t dates_seen;
   idx_t days_seen;
+  idx_t J_zones_seen;
   idx_t local_zones_seen;
   idx_t dsts_seen;
   idx_t times_seen;
@@ -624,6 +625,11 @@ item:
         pc->local_zones_seen++;
         debug_print_current_time (_("local_zone"), pc);
       }
+  | 'J'
+      {
+        pc->J_zones_seen++;
+        debug_print_current_time ("J", pc);
+      }
   | zone
       {
         pc->zones_seen++;
@@ -1153,7 +1159,8 @@ static table const time_zone_table[] =
    RFC 822 got these backwards, but RFC 5322 makes the incorrect
    treatment optional, so do them the right way here.
 
-   Note 'T' is a special case, as it is used as the separator in ISO
+   'J' is special, as it is local time.
+   'T' is also special, as it is the separator in ISO
    8601 date and time of day representation.  */
 static table const military_table[] =
 {
@@ -1166,6 +1173,7 @@ static table const military_table[] =
   { "G", tZONE,  HOUR ( 7) },
   { "H", tZONE,  HOUR ( 8) },
   { "I", tZONE,  HOUR ( 9) },
+  { "J", 'J',    0 },
   { "K", tZONE,  HOUR (10) },
   { "L", tZONE,  HOUR (11) },
   { "M", tZONE,  HOUR (12) },
@@ -1816,6 +1824,7 @@ parse_datetime_body (struct timespec *result, char const 
*p,
   pc.dates_seen = 0;
   pc.days_seen = 0;
   pc.times_seen = 0;
+  pc.J_zones_seen = 0;
   pc.local_zones_seen = 0;
   pc.dsts_seen = 0;
   pc.zones_seen = 0;
@@ -1941,7 +1950,7 @@ parse_datetime_body (struct timespec *result, char const 
*p,
   else
     {
       if (1 < (pc.times_seen | pc.dates_seen | pc.days_seen | pc.dsts_seen
-               | (pc.local_zones_seen + pc.zones_seen)))
+               | (pc.J_zones_seen + pc.local_zones_seen + pc.zones_seen)))
         {
           if (debugging (&pc))
             {
@@ -1953,7 +1962,7 @@ parse_datetime_body (struct timespec *result, char const 
*p,
                 dbg_printf ("error: seen multiple days parts\n");
               if (pc.dsts_seen > 1)
                 dbg_printf ("error: seen multiple daylight-saving parts\n");
-              if ((pc.local_zones_seen + pc.zones_seen) > 1)
+              if ((pc.J_zones_seen + pc.local_zones_seen + pc.zones_seen) > 1)
                 dbg_printf ("error: seen multiple time-zone parts\n");
             }
           goto fail;
diff --git a/tests/test-parse-datetime.c b/tests/test-parse-datetime.c
index 4310ee8a3d..6dbcb3ac93 100644
--- a/tests/test-parse-datetime.c
+++ b/tests/test-parse-datetime.c
@@ -151,6 +151,16 @@ main (_GL_UNUSED int argc, char **argv)
   ASSERT (expected.tv_sec == result.tv_sec
           && expected.tv_nsec == result.tv_nsec);
 
+  /* ISO 8601 extended date and time of day representation,
+     ' ' separator, 'J' (local) time zone */
+  p = "2011-05-01 11:55:18J";
+  expected.tv_sec = ref_time - gmtoff;
+  expected.tv_nsec = 0;
+  ASSERT (parse_datetime (&result, p, 0));
+  LOG (p, expected, result);
+  ASSERT (expected.tv_sec == result.tv_sec
+          && expected.tv_nsec == result.tv_nsec);
+
 
   /* ISO 8601, extended date and time of day representation,
      'T' separator, UTC */
-- 
2.36.1