From c0619f08e6c608fd6464d2f0c6970ef0bbfb9ecf Mon Sep 17 00:00:00 2001 From: "Rebecca N. Palmer" Date: Fri, 11 Oct 2024 09:38:52 +0100 Subject: [PATCH 1/3] gdatetime test: Do not assume PST8PDT was always exactly -8/-7 In newer tzdata, it is an alias for America/Los_Angeles, which has a slightly different meaning: DST did not exist there before 1883. As a result, we can no longer hard-code the knowledge that interval 0 is standard time and interval 1 is summer time, and instead we need to look up the correct intervals from known timestamps. Resolves: https://gitlab.gnome.org/GNOME/glib/-/issues/3502 Bug-Debian: https://bugs.debian.org/1084190 [smcv: expand commit message, fix whitespace] Signed-off-by: Simon McVittie --- glib/tests/gdatetime.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/glib/tests/gdatetime.c b/glib/tests/gdatetime.c index 3a5aa9616..ea8dc5a77 100644 --- a/glib/tests/gdatetime.c +++ b/glib/tests/gdatetime.c @@ -2931,6 +2931,7 @@ test_posix_parse (void) { GTimeZone *tz; GDateTime *gdt1, *gdt2; + gint i1, i2; /* Check that an unknown zone name falls back to UTC. */ G_GNUC_BEGIN_IGNORE_DEPRECATIONS @@ -2954,16 +2955,25 @@ test_posix_parse (void) /* This fails rules_from_identifier on Unix (though not on Windows) * but passes anyway because PST8PDT is a zone name. + * + * Intervals i1 and i2 (rather than 0 and 1) are needed because in + * recent tzdata, PST8PDT may be an alias for America/Los_Angeles, + * and hence be aware that DST has not always existed. + * https://bugs.debian.org/1084190 */ tz = g_time_zone_new_identifier ("PST8PDT"); g_assert_nonnull (tz); g_assert_cmpstr (g_time_zone_get_identifier (tz), ==, "PST8PDT"); - g_assert_cmpstr (g_time_zone_get_abbreviation (tz, 0), ==, "PST"); - g_assert_cmpint (g_time_zone_get_offset (tz, 0), ==, - 8 * 3600); - g_assert (!g_time_zone_is_dst (tz, 0)); - g_assert_cmpstr (g_time_zone_get_abbreviation (tz, 1), ==, "PDT"); - g_assert_cmpint (g_time_zone_get_offset (tz, 1), ==,- 7 * 3600); - g_assert (g_time_zone_is_dst (tz, 1)); + /* a date in winter = non-DST */ + i1 = g_time_zone_find_interval (tz, G_TIME_TYPE_STANDARD, 0); + /* approximately 6 months in seconds, i.e. a date in summer = DST */ + i2 = g_time_zone_find_interval (tz, G_TIME_TYPE_DAYLIGHT, 15000000); + g_assert_cmpstr (g_time_zone_get_abbreviation (tz, i1), ==, "PST"); + g_assert_cmpint (g_time_zone_get_offset (tz, i1), ==, - 8 * 3600); + g_assert (!g_time_zone_is_dst (tz, i1)); + g_assert_cmpstr (g_time_zone_get_abbreviation (tz, i2), ==, "PDT"); + g_assert_cmpint (g_time_zone_get_offset (tz, i2), ==,- 7 * 3600); + g_assert (g_time_zone_is_dst (tz, i2)); g_time_zone_unref (tz); tz = g_time_zone_new_identifier ("PST8PDT6:32:15"); From 30e9cfa5733003cd1079e0e9e8a4bff1a191171a Mon Sep 17 00:00:00 2001 From: Simon McVittie Date: Fri, 18 Oct 2024 11:03:19 +0100 Subject: [PATCH 2/3] gdatetime test: Try to make PST8PDT test more obviously correct Instead of using timestamp 0 as a magic number (in this case interpreted as 1970-01-01T00:00:00-08:00), calculate a timestamp from a recent year/month/day in winter, in this case 2024-01-01T00:00:00-08:00. Similarly, instead of using a timestamp 15 million seconds later (1970-06-23T15:40:00-07:00), calculate a timestamp from a recent year/month/day in summer, in this case 2024-07-01T00:00:00-07:00. Signed-off-by: Simon McVittie --- glib/tests/gdatetime.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/glib/tests/gdatetime.c b/glib/tests/gdatetime.c index ea8dc5a77..85fffdd06 100644 --- a/glib/tests/gdatetime.c +++ b/glib/tests/gdatetime.c @@ -2955,19 +2955,16 @@ test_posix_parse (void) /* This fails rules_from_identifier on Unix (though not on Windows) * but passes anyway because PST8PDT is a zone name. - * - * Intervals i1 and i2 (rather than 0 and 1) are needed because in - * recent tzdata, PST8PDT may be an alias for America/Los_Angeles, - * and hence be aware that DST has not always existed. - * https://bugs.debian.org/1084190 */ tz = g_time_zone_new_identifier ("PST8PDT"); g_assert_nonnull (tz); g_assert_cmpstr (g_time_zone_get_identifier (tz), ==, "PST8PDT"); /* a date in winter = non-DST */ - i1 = g_time_zone_find_interval (tz, G_TIME_TYPE_STANDARD, 0); - /* approximately 6 months in seconds, i.e. a date in summer = DST */ - i2 = g_time_zone_find_interval (tz, G_TIME_TYPE_DAYLIGHT, 15000000); + gdt1 = g_date_time_new (tz, 2024, 1, 1, 0, 0, 0); + i1 = g_time_zone_find_interval (tz, G_TIME_TYPE_STANDARD, g_date_time_to_unix (gdt1)); + /* a date in summer = DST */ + gdt2 = g_date_time_new (tz, 2024, 7, 1, 0, 0, 0); + i2 = g_time_zone_find_interval (tz, G_TIME_TYPE_DAYLIGHT, g_date_time_to_unix (gdt2)); g_assert_cmpstr (g_time_zone_get_abbreviation (tz, i1), ==, "PST"); g_assert_cmpint (g_time_zone_get_offset (tz, i1), ==, - 8 * 3600); g_assert (!g_time_zone_is_dst (tz, i1)); @@ -2975,6 +2972,8 @@ test_posix_parse (void) g_assert_cmpint (g_time_zone_get_offset (tz, i2), ==,- 7 * 3600); g_assert (g_time_zone_is_dst (tz, i2)); g_time_zone_unref (tz); + g_date_time_unref (gdt1); + g_date_time_unref (gdt2); tz = g_time_zone_new_identifier ("PST8PDT6:32:15"); #ifdef G_OS_WIN32 From fe2699369f79981dcf913af4cfd98b342b84a9c1 Mon Sep 17 00:00:00 2001 From: Simon McVittie Date: Fri, 18 Oct 2024 11:23:42 +0100 Subject: [PATCH 3/3] gdatetime test: Fall back if legacy System V PST8PDT is not available On recent versions of Debian, PST8PDT is part of the tzdata-legacy package, which is not always installed and might disappear in future. Successfully tested with and without tzdata-legacy on Debian unstable. Signed-off-by: Simon McVittie --- glib/tests/gdatetime.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) diff --git a/glib/tests/gdatetime.c b/glib/tests/gdatetime.c index 85fffdd06..b3e5e86c0 100644 --- a/glib/tests/gdatetime.c +++ b/glib/tests/gdatetime.c @@ -2932,6 +2932,7 @@ test_posix_parse (void) GTimeZone *tz; GDateTime *gdt1, *gdt2; gint i1, i2; + const char *expect_id; /* Check that an unknown zone name falls back to UTC. */ G_GNUC_BEGIN_IGNORE_DEPRECATIONS @@ -2954,11 +2955,25 @@ test_posix_parse (void) g_time_zone_unref (tz); /* This fails rules_from_identifier on Unix (though not on Windows) - * but passes anyway because PST8PDT is a zone name. + * but can pass anyway because PST8PDT is a legacy System V zone name. */ tz = g_time_zone_new_identifier ("PST8PDT"); + expect_id = "PST8PDT"; + +#ifndef G_OS_WIN32 + /* PST8PDT is in tzdata's "backward" set, packaged as tzdata-legacy and + * not always present in some OSs; fall back to the equivalent geographical + * name if the "backward" time zones are absent. */ + if (tz == NULL) + { + g_test_message ("Legacy PST8PDT time zone not available, falling back"); + tz = g_time_zone_new_identifier ("America/Los_Angeles"); + expect_id = "America/Los_Angeles"; + } +#endif + g_assert_nonnull (tz); - g_assert_cmpstr (g_time_zone_get_identifier (tz), ==, "PST8PDT"); + g_assert_cmpstr (g_time_zone_get_identifier (tz), ==, expect_id); /* a date in winter = non-DST */ gdt1 = g_date_time_new (tz, 2024, 1, 1, 0, 0, 0); i1 = g_time_zone_find_interval (tz, G_TIME_TYPE_STANDARD, g_date_time_to_unix (gdt1));