From 9c4469d0399164697f6716d0e960daa7fbe259f2 Mon Sep 17 00:00:00 2001
From: John Ralls <jralls@ceridwen.us>
Date: Fri, 27 Apr 2018 13:27:47 -0700
Subject: [PATCH] Bug 795405 - All Dates in Price Database Off-By-One After 3.0
 Upgrade

Also Bug 791825 - Accounting Period dates off by 1.
The DST start/end dates were reversed *and* the DST offset had the wrong
sign in Windows, resulting in the effective timezone always being one to
the west off (i.e. PDT was -9 and PST was -8).
---
 libgnucash/engine/gnc-timezone.cpp            | 18 ++++++++++++------
 libgnucash/engine/test/gtest-gnc-timezone.cpp | 13 +++++++++++--
 po/POTFILES.in                                |  1 -
 3 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/libgnucash/engine/gnc-timezone.cpp b/libgnucash/engine/gnc-timezone.cpp
index 3d6959fb5f..876df2aac5 100644
--- a/libgnucash/engine/gnc-timezone.cpp
+++ b/libgnucash/engine/gnc-timezone.cpp
@@ -150,9 +150,15 @@ zone_from_regtzi (const RegTZI& regtzi, time_zone_names names)
 {
     using ndate = boost::gregorian::nth_day_of_the_week_in_month;
     using nth_day_rule = boost::local_time::nth_day_of_the_week_in_month_dst_rule;
-
+    /* Note that Windows runs its biases backwards from POSIX and
+     * boost::date_time: It's the value added to the local time to get
+     * GMT rather than the value added to GMT to get local time; for
+     * the same reason the DaylightBias is negative as one generally
+     * adds an hour less to the local time to get GMT. Biases are in
+     * minutes.
+     */
     duration std_off (0, regtzi.StandardBias - regtzi.Bias, 0);
-    duration dlt_off (0, regtzi.DaylightBias, 0);
+    duration dlt_off (0, -regtzi.DaylightBias, 0);
     duration start_time (regtzi.StandardDate.wHour, regtzi.StandardDate.wMinute,
 			 regtzi.StandardDate.wSecond);
     duration end_time (regtzi.DaylightDate.wHour, regtzi.DaylightDate.wMinute,
@@ -165,10 +171,10 @@ zone_from_regtzi (const RegTZI& regtzi, time_zone_names names)
     {
 	try
 	{
-	    ndate start (std_week_num, regtzi.StandardDate.wDayOfWeek,
-			 regtzi.StandardDate.wMonth);
-	    ndate end(dlt_week_num, regtzi.DaylightDate.wDayOfWeek,
-		      regtzi.DaylightDate.wMonth);
+	    ndate start (dlt_week_num, regtzi.DaylightDate.wDayOfWeek,
+			 regtzi.DaylightDate.wMonth);
+	    ndate end(std_week_num, regtzi.StandardDate.wDayOfWeek,
+		      regtzi.StandardDate.wMonth);
 	    dates.reset(new nth_day_rule (start, end));
 	}
 	catch (boost::gregorian::bad_month& err)
diff --git a/libgnucash/engine/test/gtest-gnc-timezone.cpp b/libgnucash/engine/test/gtest-gnc-timezone.cpp
index 963466c32b..a676ff1a94 100644
--- a/libgnucash/engine/test/gtest-gnc-timezone.cpp
+++ b/libgnucash/engine/test/gtest-gnc-timezone.cpp
@@ -46,17 +46,21 @@ TEST(gnc_timezone_constructors, test_pacific_time_constructor)
     TimeZoneProvider tzp (timezone);
     EXPECT_NO_THROW (tzp.get(2012));
     TZ_Ptr tz = tzp.get (2012);
-
     EXPECT_FALSE(tz->std_zone_abbrev().empty());
 #if PLATFORM(WINDOWS)
     EXPECT_TRUE(tz->std_zone_abbrev() == timezone);
+    EXPECT_TRUE(tz->dst_zone_abbrev() == "Pacific Daylight Time");
 #else
     EXPECT_TRUE(tz->std_zone_abbrev() == "PST");
     EXPECT_TRUE(tz->dst_zone_abbrev() == "PDT");
 #endif
     EXPECT_EQ(-8, tz->base_utc_offset().hours());
-
+    auto dst_offset = tz->base_utc_offset() + tz->dst_offset();
+    EXPECT_EQ(-7, dst_offset.hours());
     EXPECT_EQ(12, tz->dst_local_start_time (2017).date().day());
+    EXPECT_EQ(3, tz->dst_local_start_time (2017).date().month());
+    EXPECT_EQ(5, tz->dst_local_end_time (2017).date().day());
+    EXPECT_EQ(11, tz->dst_local_end_time (2017).date().month());
 }
 
 #if !PLATFORM(WINDOWS)
@@ -284,8 +288,13 @@ TEST(gnc_timezone_constructors, test_IANA_Minsk_tz)
 
 TEST(gnc_timezone_constructors, test_bogus_time_constructor)
 {
+#if PLATFORM(WINDOWS)
+    EXPECT_THROW(TimeZoneProvider tzp ("New York Standard Time"),
+		 std::invalid_argument);
+#else
     TimeZoneProvider tzp ("New York Standard Time");
     TimeZoneProvider machine ("");
     EXPECT_EQ(machine.get(2006)->std_zone_abbrev(),
 	      tzp.get(2006)->std_zone_abbrev());
+#endif
 }
diff --git a/po/POTFILES.in b/po/POTFILES.in
index dc896a7716..9cdb537304 100644
--- a/po/POTFILES.in
+++ b/po/POTFILES.in
@@ -449,7 +449,6 @@ gnucash/report/report-system/html-acct-table.scm
 gnucash/report/report-system/html-barchart.scm
 gnucash/report/report-system/html-document.scm
 gnucash/report/report-system/html-fonts.scm
-gnucash/report/report-system/html-jqplot.scm
 gnucash/report/report-system/html-linechart.scm
 gnucash/report/report-system/html-piechart.scm
 gnucash/report/report-system/html-scatter.scm