branch: elpa/datetime
commit 8cfa779858187c6149cf0b4048005f59ebac271b
Author: Paul Pogonyshev <pogonys...@gmail.com>
Commit: Paul Pogonyshev <pogonys...@gmail.com>
Improve system timezone determining; especially important for Windows.
---
datetime.el | 10 +++++++---
dev/HarvestData.java | 46 +++++++++++++++++++++++++++++++++++++++++++++-
test/base.el | 23 +++++++++++++++++++++++
timezone-data.extmap | Bin 900579 -> 902807 bytes
4 files changed, 75 insertions(+), 4 deletions(-)
diff --git a/datetime.el b/datetime.el
index c7bd600817..7b61037f69 100644
--- a/datetime.el
+++ b/datetime.el
@@ -305,8 +305,12 @@ form:
"?"))))
(if (extmap-contains-key datetime--timezone-extmap system-timezone)
system-timezone
- (error "Failed to determine system timezone%s; consider customizing
`datetime-timezone' variable"
- (if (eq system-timezone '\?) "" (format-message " (found raw
value: `%s')" system-timezone)))))))
+ (let* ((aliases (extmap-get datetime--timezone-extmap :aliases t))
+ (entry (assq system-timezone aliases)))
+ (if entry
+ (cdr entry)
+ (error "Failed to determine system timezone%s; consider
customizing `datetime-timezone' variable"
+ (if (eq system-timezone '\?) "" (format-message " (found
raw value: `%s')" system-timezone)))))))))
(defun datetime--parse-pattern (type pattern options)
@@ -2064,7 +2068,7 @@ create based on timezones `datetime' knows about and
their rules.
Locale-specific timezone names are contained in a different
database. See `datetime-timezone-name-database-version'."
- 7)
+ 8)
(defun datetime-timezone-name-database-version ()
"Return timezone name database version, a simple integer.
diff --git a/dev/HarvestData.java b/dev/HarvestData.java
index 4b681db9d8..59a71c4d0e 100644
--- a/dev/HarvestData.java
+++ b/dev/HarvestData.java
@@ -325,7 +325,13 @@ public class HarvestData
protected static void printTimezoneData () throws Exception
{
- Map <ZoneId, List <Object>> data = new LinkedHashMap <> ();
+ var data = new LinkedHashMap
<ZoneId, List <Object>> ();
+ var aliases = new LinkedHashMap
<String, Set <ZoneId>> ();
+ var timezones_with_matching_abbreviations = new HashSet
<ZoneId> ();
+ var abbreviation_retriever =
DateTimeFormatter.ofPattern ("z", Locale.ENGLISH);
+ var utc_formatter =
DateTimeFormatter.ofPattern ("yyyy-MM-dd HH:mm:ss z");
+ Instant[] abbreviations_at = { Instant.from
(utc_formatter.parse ("2020-01-01 00:00:00 UTC")),
+ Instant.from
(utc_formatter.parse ("2020-07-01 00:00:00 UTC")) };
for (ZoneId timezone : getAllTimezones ()) {
ZoneRules rules = timezone.getRules ();
@@ -434,12 +440,50 @@ public class HarvestData
zone_data.add (toLispList (transition_rule_data));
data.put (timezone, zone_data);
+
+ for (var at : abbreviations_at) {
+ var abbreviation = abbreviation_retriever.format
(ZonedDateTime.ofInstant (at, timezone));
+ if (abbreviation.equals (timezone.getId ()))
+ timezones_with_matching_abbreviations.add (timezone);
+ else
+ aliases.computeIfAbsent (abbreviation, __ -> new
HashSet <> ()).add (timezone);
+ }
}
}
+ // When computing timezone alias map we use these rules:
+ // - if timezone identifier matches its normal abbreviation, its DST
abbreviation
+ // becomes an alias (example: "CEST" becomes an alias for "CET");
+ // - else both abbreviations become an alias for the timezone, but
only if they
+ // don't clash with anything else (example: "EGT" and "EGST" are
both aliases
+ // for "America/Scoresbysund").
+ var timezones_with_conflicting_aliases = new HashSet <ZoneId> ();
+ for (var timezones : aliases.values ()) {
+ if (timezones.size () > 1)
+ timezones_with_conflicting_aliases.addAll (timezones);
+ }
+
+ timezones_with_conflicting_aliases.removeAll
(timezones_with_matching_abbreviations);
+
+ for (var it = aliases.values ().iterator (); it.hasNext ();) {
+ var with_this_alias = it.next ();
+ with_this_alias.removeAll (timezones_with_conflicting_aliases);
+ if (with_this_alias.size () != 1)
+ it.remove ();
+ }
+
System.out.println ("(");
+
for (Map.Entry <ZoneId, List <Object>> entry : data.entrySet ())
System.out.format ("(%s\n %s)\n", entry.getKey (), entry.getValue
().stream ().map (String::valueOf).collect (Collectors.joining ("\n ")));
+
+ // Aliases don't go into names: they are relatively few and are not
used for
+ // formatting or parsing, currently only when determining OS timezone.
+ System.out.format ("(:aliases\n %s)\n",
+ aliases.entrySet ().stream ()
+ .map ((entry) -> String.format ("(%s . %s)",
entry.getKey (), entry.getValue ().iterator ().next ().getId ()))
+ .collect (Collectors.joining ("\n ")));
+
System.out.println (")");
}
diff --git a/test/base.el b/test/base.el
index c20b1e5df9..c45682a075 100644
--- a/test/base.el
+++ b/test/base.el
@@ -89,6 +89,24 @@
(datetime--test-set-up-parser datetime--test-timezone
datetime--test-locale datetime--test-pattern
,@body)))
+;; Copied from Eldev source code, see documentation there.
+(defmacro datetime--advised (spec &rest body)
+ (declare (indent 1) (debug (sexp body)))
+ (let ((symbol (nth 0 spec))
+ (where (nth 1 spec))
+ (function (nth 2 spec))
+ (props (nthcdr 3 spec))
+ (fn (make-symbol "$fn")))
+ `(let ((,fn ,function))
+ (when ,fn
+ (if (advice-member-p ,fn ,symbol)
+ (setf ,fn nil)
+ (advice-add ,symbol ,where ,fn ,@props)))
+ (unwind-protect
+ ,(macroexp-progn body)
+ (when ,fn
+ (advice-remove ,symbol ,fn))))))
+
(defun datetime--test (command times)
(unless (listp times)
(setq times (list times)))
@@ -211,5 +229,10 @@ am-pm = %S"
(dotimes (k length)
(should (stringp (aref value k))))))))))
+(ert-deftest datetime--determine-system-timezone ()
+ (datetime--advised ('current-time-zone :override (lambda () '(7200 "CEST")))
+ (let ((system-type 'this-system-type-is-not-specialcase))
+ (should (eq (datetime--determine-system-timezone) 'CET)))))
+
(provide 'test/base)
diff --git a/timezone-data.extmap b/timezone-data.extmap
index 731fd92781..fbac550399 100644
Binary files a/timezone-data.extmap and b/timezone-data.extmap differ
