Attempt to better handle screwy MSFT time zone information

* Exchange appears to send time zond data that doesn't really match
  any time zone in our database; in these cases, we have been
  returning a random one with the same bias (base offset w/o DST)
* In this CL, we try to do better by giving the time zone information
  a bit more slack when the regular determination fails (we allow
  the hour of change to be up to 4 hours different from expected,
  rather than one minute).  This is certainly better, though I do
  not have an explanation from MSFT about the reason for the
  erroneous data.
* Updated unit tests to confirm that we don't break any existing
  code and do, in fact, handle the case reported below as a P1/S1
  bug.

Bug: 5605219
Change-Id: I8c17a687404204aff4feb1c3009adde279110cab

1 files changed, 18 insertions, 0 deletions

diff --git a/tests/src/com/android/exchange/utility/CalendarUtilitiesTests.java b/tests/src/com/android/exchange/utility/CalendarUtilitiesTests.java
index b883b5a2..0ecdb8fd 100644
--- a/tests/src/com/android/exchange/utility/CalendarUtilitiesTests.java
+++ b/tests/src/com/android/exchange/utility/CalendarUtilitiesTests.java
@@ -103,6 +103,13 @@ public class CalendarUtilitiesTests extends SyncAdapterTestCase<CalendarSyncAdap
         "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAEgAYQB3AGEAaQBpAGEAbgAgAEQAYQB5AGwAaQBnAGgAdAAgAFQA" +
         "aQBtAGUAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA==";
 
+    // This is time zone sent by Exchange 2007, apparently; the start time of DST for the eastern
+    // time zone (EST) is off by two hours, which we should correct in our new "lenient" code
+    private static final String LENIENT_EASTERN_TIME =
+        "LAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA" +
+        "AAAAAAAAAAsAAAABAAIAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA" +
+        "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAMAAAACAAAAAAAAAAAAxP///w==";
+
     private static final String ORGANIZER = "organizer@server.com";
     private static final String ATTENDEE = "attendee@server.com";
 
@@ -132,6 +139,17 @@ public class CalendarUtilitiesTests extends SyncAdapterTestCase<CalendarSyncAdap
         assertEquals("Asia/Calcutta", tz.getID());
         tz = CalendarUtilities.tziStringToTimeZone(AUSTRALIA_ACT_TIME);
         assertEquals("Australia/ACT", tz.getID());
+
+        // Test peculiar MS sent EST data with and without lenient precision; send standard
+        // precision + 1 (i.e. 1ms) to make sure the code doesn't automatically flip to lenient
+        // when the tz isn't found
+        tz = CalendarUtilities.tziStringToTimeZoneImpl(LENIENT_EASTERN_TIME,
+                CalendarUtilities.STANDARD_DST_PRECISION+1);
+        assertEquals("America/Atikokan", tz.getID());
+        tz = CalendarUtilities.tziStringToTimeZoneImpl(LENIENT_EASTERN_TIME,
+                CalendarUtilities.LENIENT_DST_PRECISION);
+        assertEquals("America/Detroit", tz.getID());
+
         tz = CalendarUtilities.tziStringToTimeZone(GMT_UNKNOWN_DAYLIGHT_TIME);
         int bias = tz.getOffset(System.currentTimeMillis());
         assertEquals(0, bias);