fix(retention): handle timezones with daylight saving transitions cor…

…rectly (#17305)
PostHog · Sep 6, 2023 · bc091c6 · bc091c6
1 parent e00caf4
commit bc091c6
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Showing 4 changed files with 8 additions and 5 deletions.
diff --git a/frontend/src/scenes/retention/retentionLineGraphLogic.ts b/frontend/src/scenes/retention/retentionLineGraphLogic.ts
@@ -71,7 +71,7 @@ export const retentionLineGraphLogic = kea<retentionLineGraphLogicType>({
                         label: cohortRetention.date
                             ? period === 'Hour'
                                 ? dayjs(cohortRetention.date).format('MMM D, h A')
-                                : dayjs.utc(cohortRetention.date).format('MMM D')
+                                : dayjs(cohortRetention.date).format('MMM D')
                             : cohortRetention.label,
                         data:
                             retention_reference === 'previous'

diff --git a/frontend/src/scenes/retention/retentionTableLogic.ts b/frontend/src/scenes/retention/retentionTableLogic.ts
@@ -73,7 +73,7 @@ export const retentionTableLogic = kea<retentionTableLogicType>({
                         ? results[rowIndex].label
                         : period === 'Hour'
                         ? dayjs(results[rowIndex].date).format('MMM D, h A')
-                        : dayjs.utc(results[rowIndex].date).format('MMM D'),
+                        : dayjs(results[rowIndex].date).format('MMM D'),
                     // Second column is the first value (which is essentially the total)
                     results[rowIndex].values[0].count,
                     // All other columns are rendered as percentage

diff --git a/posthog/queries/retention/retention.py b/posthog/queries/retention/retention.py
@@ -109,8 +109,10 @@ def construct_url(first_day):
                     for day in range(filter.total_intervals - first_day)
                 ],
                 "label": "{} {}".format(filter.period, first_day),
-                "date": (filter.date_from + RetentionFilter.determine_time_delta(first_day, filter.period)[0]).replace(
-                    tzinfo=pytz.timezone(team.timezone)
+                "date": pytz.timezone(team.timezone).localize(
+                    (filter.date_from + RetentionFilter.determine_time_delta(first_day, filter.period)[0]).replace(
+                        tzinfo=None
+                    )
                 ),
                 "people_url": construct_url(first_day),
             }

diff --git a/posthog/queries/test/test_retention.py b/posthog/queries/test/test_retention.py
@@ -1270,7 +1270,8 @@ def test_timezones(self):
                 ["Day 0", "Day 1", "Day 2", "Day 3", "Day 4", "Day 5", "Day 6", "Day 7", "Day 8", "Day 9", "Day 10"],
             )
 
-            self.assertEqual(result_pacific[0]["date"], datetime(2020, 6, 10, 0, tzinfo=pytz.timezone("US/Pacific")))
+            self.assertEqual(result_pacific[0]["date"], pytz.timezone("US/Pacific").localize(datetime(2020, 6, 10)))
+            self.assertEqual(result_pacific[0]["date"].isoformat(), "2020-06-10T00:00:00-07:00")
 
             self.assertEqual(
                 pluck(result, "values", "count"),