gdatetime: Disable ERA support on platforms which don’t support this

So far, that’s BSD: it supports `nl_langinfo()`, but not `ERA`.

Signed-off-by: Philip Withnall <pwithnall@gnome.org>

Helps: #3119

glib/gdatetime.c

@@ -165,11 +165,8 @@ static const guint16 days_in_year[2][13] =
 #define GET_AMPM_IS_LOCALE TRUE
 
 #define PREFERRED_DATE_TIME_FMT nl_langinfo (D_T_FMT)
-#define PREFERRED_ERA_DATE_TIME_FMT nl_langinfo (ERA_D_T_FMT)
 #define PREFERRED_DATE_FMT nl_langinfo (D_FMT)
-#define PREFERRED_ERA_DATE_FMT nl_langinfo (ERA_D_FMT)
 #define PREFERRED_TIME_FMT nl_langinfo (T_FMT)
-#define PREFERRED_ERA_TIME_FMT nl_langinfo (ERA_T_FMT)
 #define PREFERRED_12HR_TIME_FMT nl_langinfo (T_FMT_AMPM)
 
 static const gint weekday_item[2][7] =
@@ -193,10 +190,6 @@ static const gint month_item[2][12] =
 #define MONTH_FULL(d) nl_langinfo (month_item[1][g_date_time_get_month (d) - 1])
 #define MONTH_FULL_IS_LOCALE TRUE
 
-#define ERA_DESCRIPTION nl_langinfo (ERA)
-#define ERA_DESCRIPTION_IS_LOCALE TRUE
-#define ERA_DESCRIPTION_N_SEGMENTS (int) (gintptr) nl_langinfo (_NL_TIME_ERA_NUM_ENTRIES)
-
 #else
 
 #define GET_AMPM(d)          (get_fallback_ampm (g_date_time_get_hour (d)))
@@ -204,15 +197,12 @@ static const gint month_item[2][12] =
 
 /* Translators: this is the preferred format for expressing the date and the time */
 #define PREFERRED_DATE_TIME_FMT C_("GDateTime", "%a %b %e %H:%M:%S %Y")
-#define PREFERRED_ERA_DATE_TIME_FMT PREFERRED_DATE_TIME_FMT
 
 /* Translators: this is the preferred format for expressing the date */
 #define PREFERRED_DATE_FMT C_("GDateTime", "%m/%d/%y")
-#define PREFERRED_ERA_DATE_FMT PREFERRED_DATE_FMT
 
 /* Translators: this is the preferred format for expressing the time */
 #define PREFERRED_TIME_FMT C_("GDateTime", "%H:%M:%S")
-#define PREFERRED_ERA_TIME_FMT PREFERRED_TIME_FMT
 
 /* Translators: this is the preferred format for expressing 12 hour time */
 #define PREFERRED_12HR_TIME_FMT C_("GDateTime", "%I:%M:%S %p")
@@ -232,10 +222,6 @@ static const gint month_item[2][12] =
 #define MONTH_FULL(d)         (get_month_name_standalone (g_date_time_get_month (d)))
 #define MONTH_FULL_IS_LOCALE  FALSE
 
-#define ERA_DESCRIPTION NULL
-#define ERA_DESCRIPTION_IS_LOCALE FALSE
-#define ERA_DESCRIPTION_N_SEGMENTS 0
-
 static const gchar *
 get_month_name_standalone (gint month)
 {
@@ -572,6 +558,28 @@ get_month_name_abbr_with_day (gint month)
 
 #endif  /* HAVE_LANGINFO_ABALTMON */
 
+#ifdef HAVE_LANGINFO_ERA
+
+#define PREFERRED_ERA_DATE_TIME_FMT nl_langinfo (ERA_D_T_FMT)
+#define PREFERRED_ERA_DATE_FMT nl_langinfo (ERA_D_FMT)
+#define PREFERRED_ERA_TIME_FMT nl_langinfo (ERA_T_FMT)
+
+#define ERA_DESCRIPTION nl_langinfo (ERA)
+#define ERA_DESCRIPTION_IS_LOCALE TRUE
+#define ERA_DESCRIPTION_N_SEGMENTS (int) (gintptr) nl_langinfo (_NL_TIME_ERA_NUM_ENTRIES)
+
+#else  /* if !HAVE_LANGINFO_ERA */
+
+#define PREFERRED_ERA_DATE_TIME_FMT PREFERRED_DATE_TIME_FMT
+#define PREFERRED_ERA_DATE_FMT PREFERRED_DATE_FMT
+#define PREFERRED_ERA_TIME_FMT PREFERRED_TIME_FMT
+
+#define ERA_DESCRIPTION NULL
+#define ERA_DESCRIPTION_IS_LOCALE FALSE
+#define ERA_DESCRIPTION_N_SEGMENTS 0
+
+#endif  /* !HAVE_LANGINFO_ERA */
+
 /* Format AM/PM indicator if the locale does not have a localized version. */
 static const gchar *
 get_fallback_ampm (gint hour)
@@ -2962,10 +2970,13 @@ date_time_lookup_era (GDateTime *datetime,
 
           if (era_description_str != NULL)
             static_era_description = _g_era_description_parse (era_description_str);
+          if (static_era_description == NULL)
+            g_warning ("Could not parse ERA description: %s", era_description_str);
+        }
+      else
+        {
+          g_clear_pointer (&static_era_description, g_ptr_array_unref);
         }
-
-      if (static_era_description == NULL)
-        g_warning ("Could not parse ERA description: %s", era_description_str);
 
       g_free (tmp);
 

glib/tests/gdatetime.c

@@ -1725,12 +1725,21 @@ test_non_utf8_printf (void)
   TEST_PRINTF ("%%", "%");
   TEST_PRINTF ("%", "");
   TEST_PRINTF ("%9", NULL);
+#ifdef HAVE_LANGINFO_ERA
   TEST_PRINTF ("%Ec", "平成21年10月24日 00時00分00秒");
   TEST_PRINTF ("%EC", "平成");
   TEST_PRINTF ("%Ex", "平成21年10月24日");
   TEST_PRINTF ("%EX", "00時00分00秒");
   TEST_PRINTF ("%Ey", "21");
   TEST_PRINTF ("%EY", "平成21年");
+#else
+  TEST_PRINTF ("%Ec", "平成21年10月24日 00時00分00秒");
+  TEST_PRINTF ("%EC", "平成");
+  TEST_PRINTF ("%Ex", "2009\345\271\26410\346\234\21024\346\227\245");
+  TEST_PRINTF ("%EX", "00\346\231\20200\345\210\20600\347\247\222");
+  TEST_PRINTF ("%Ey", "09");
+  TEST_PRINTF ("%EY", "2009");
+#endif
 
   setlocale (LC_ALL, oldlocale);
   g_free (oldlocale);
@@ -1889,14 +1898,25 @@ test_modifiers (void)
   setlocale (LC_ALL, "en_GB.utf-8");
   if (strstr (setlocale (LC_ALL, NULL), "en_GB") != NULL)
     {
+#ifndef __APPLE__
       TEST_PRINTF_DATE (2009, 1, 1, "%c", "thu 01 jan 2009 00:00:00 utc");
       TEST_PRINTF_DATE (2009, 1, 1, "%Ec", "thu 01 jan 2009 00:00:00 utc");
+#else
+      /* macOS uses a figure space (U+2007) to pad the day */
+      TEST_PRINTF_DATE (2009, 1, 1, "%c", "thu " "\xe2\x80\x87" "1 jan 00:00:00 2009");
+      TEST_PRINTF_DATE (2009, 1, 1, "%Ec", "thu " "\xe2\x80\x87" "1 jan 00:00:00 2009");
+#endif
 
       TEST_PRINTF_DATE (2009, 1, 1, "%C", "20");
       TEST_PRINTF_DATE (2009, 1, 1, "%EC", "20");
 
+#ifndef __APPLE__
       TEST_PRINTF_DATE (2009, 1, 2, "%x", "02/01/09");
       TEST_PRINTF_DATE (2009, 1, 2, "%Ex", "02/01/09");
+#else
+      TEST_PRINTF_DATE (2009, 1, 2, "%x", "02/01/2009");
+      TEST_PRINTF_DATE (2009, 1, 2, "%Ex", "02/01/2009");
+#endif
 
       TEST_PRINTF_TIME (1, 2, 3, "%X", "01:02:03");
       TEST_PRINTF_TIME (1, 2, 3, "%EX", "01:02:03");
@@ -2252,6 +2272,7 @@ test_all_dates (void)
 static void
 test_date_time_eras_japan (void)
 {
+#ifdef HAVE_LANGINFO_ERA
   gchar *oldlocale;
 
   oldlocale = g_strdup (setlocale (LC_ALL, NULL));
@@ -2290,11 +2311,15 @@ test_date_time_eras_japan (void)
 
   setlocale (LC_ALL, oldlocale);
   g_free (oldlocale);
+#else
+  g_test_skip ("nl_langinfo(ERA) not supported, skipping era tests");
+#endif
 }
 
 static void
 test_date_time_eras_thailand (void)
 {
+#ifdef HAVE_LANGINFO_ERA
   gchar *oldlocale;
 
   oldlocale = g_strdup (setlocale (LC_ALL, NULL));
@@ -2318,6 +2343,9 @@ test_date_time_eras_thailand (void)
 
   setlocale (LC_ALL, oldlocale);
   g_free (oldlocale);
+#else
+  g_test_skip ("nl_langinfo(ERA) not supported, skipping era tests");
+#endif
 }
 
 static void

meson.build

@@ -1311,15 +1311,25 @@ if cc.links('''#include <langinfo.h>
                  str = nl_langinfo (ABMON_12);
                  str = nl_langinfo (DAY_1);
                  str = nl_langinfo (ABDAY_7);
+                 return 0;
+               }''', name : 'nl_langinfo (PM_STR)')
+  glib_conf.set('HAVE_LANGINFO_TIME', 1)
+endif
+
+# Linux glibc supports ERA, but FreeBSD and macOS don’t
+if cc.links('''#include <langinfo.h>
+               int main (int argc, char **argv) {
+                 char *str;
                  str = nl_langinfo (ERA);
                  str = nl_langinfo (ERA_D_T_FMT);
                  str = nl_langinfo (ERA_D_FMT);
                  str = nl_langinfo (ERA_T_FMT);
                  str = nl_langinfo (_NL_TIME_ERA_NUM_ENTRIES);
                  return 0;
-               }''', name : 'nl_langinfo (PM_STR)')
+               }''', name : 'nl_langinfo (ERA)')
-  glib_conf.set('HAVE_LANGINFO_TIME', 1)
+  glib_conf.set('HAVE_LANGINFO_ERA', 1)
 endif
+
 if cc.links('''#include <langinfo.h>
                int main (int argc, char ** argv) {
                  char *str;