From 550e571d0af076d918459c432bbd850245cf0702 Mon Sep 17 00:00:00 2001
From: John Mettraux <jmettraux@gmail.com>
Date: Thu, 25 Mar 2021 15:54:28 +0900
Subject: [PATCH] Ensure leaving ZH DST is OK, gh-53

---
 CHANGELOG.md      |  2 ++
 lib/fugit/cron.rb |  3 ++-
 spec/cron_spec.rb | 24 ++++++++++++++++++++++++
 3 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 628b2dd..863ca86 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,8 @@
 
 ## fugit 1.4.4 not yet released
 
+* Ensure leaving ZH DST is OK, gh-53
+
 
 ## fugit 1.4.3 released 2021-03-23
 
diff --git a/lib/fugit/cron.rb b/lib/fugit/cron.rb
index a149c9f..2dac6ee 100644
--- a/lib/fugit/cron.rb
+++ b/lib/fugit/cron.rb
@@ -92,7 +92,8 @@ def inc_month
 
       def inc_day
         inc((24 - @t.hour) * 3600 - @t.min * 60 - @t.sec)
-        inc( - @t.hour * 3600) if @t.hour != 0 # compensate for entering DST
+        #inc( - @t.hour * 3600) if @t.hour != 0 # compensate for entering DST
+        inc( - @t.hour * 3600) if @t.hour > 0 && @t.hour < 7
       end
       def inc_hour
         inc((60 - @t.min) * 60 - @t.sec)
diff --git a/spec/cron_spec.rb b/spec/cron_spec.rb
index c567e22..b3083c5 100644
--- a/spec/cron_spec.rb
+++ b/spec/cron_spec.rb
@@ -311,6 +311,30 @@
         end
       end
 
+      it 'correctly increments out of DST (gh-53 e)' do
+
+        in_zone 'Europe/Zurich' do
+
+          #c = Fugit::Nat.parse('every monday at midnight')
+          c = Fugit::Cron.parse('0 0 * * 2')
+          t = EtOrbi::EoTime.parse('2021-10-18 12:00:00')
+
+          points =
+            4.times.collect do
+              t = c.next_time(t)
+              tu = t.dup.utc
+              "#{t.strftime('%F_%H:%M_%Z')}__#{tu.strftime('%F_%H:%M_%Z')}"
+            end
+
+          expect(points.join("\n")).to eq(%w[
+            2021-10-19_00:00_CEST__2021-10-18_22:00_UTC
+            2021-10-26_00:00_CEST__2021-10-25_22:00_UTC
+            2021-11-02_00:00_CET__2021-11-01_23:00_UTC
+            2021-11-09_00:00_CET__2021-11-08_23:00_UTC
+          ].join("\n"))
+        end
+      end
+
       it 'correctly increments out of DST' do
 
         in_zone 'America/Los_Angeles' do