From 957ca837d5b5d03f10cdf4b91f67e3d1f3570d9b Mon Sep 17 00:00:00 2001
From: Josh Kelley <joshkel@gmail.com>
Date: Mon, 6 Dec 2021 07:38:39 -0500
Subject: [PATCH] Specify UTC time zone for the test suite (#9945)

The controller.bar/not-grouped/on-time test was failing on my computer because the date ranges happen to cross the end of Daylight Saving Time in the U.S., so chart was generated with one more hour of time than the test fixture expected.

Using moment-timezone to specify a fixed time zone with no DST seemed like the most robust fix. (Alternatively, I could pick a date range that doesn't change DST; that ought to work.)
---
 karma.conf.js                  |  1 +
 package-lock.json              | 22 ++++++++++++++++++++++
 package.json                   |  1 +
 test/index.js                  |  4 ++++
 test/specs/scale.time.tests.js | 11 +++++++----
 5 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/karma.conf.js b/karma.conf.js
index 3a93f07eb..b122c3061 100644
--- a/karma.conf.js
+++ b/karma.conf.js
@@ -82,6 +82,7 @@ module.exports = function(karma) {
       {pattern: 'test/fixtures/**/*.json', included: false},
       {pattern: 'test/fixtures/**/*.png', included: false},
       'node_modules/moment/min/moment.min.js',
+      'node_modules/moment-timezone/builds/moment-timezone-with-data.min.js',
       {pattern: 'test/index.js', watched: false},
       {pattern: 'test/BasicChartWebWorker.js', included: false},
       {pattern: 'src/index.js', watched: false},
diff --git a/package-lock.json b/package-lock.json
index 66f1ceea1..1d94b187c 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -47,6 +47,7 @@
                 "luxon": "^1.26.0",
                 "markdown-it-include": "^2.0.0",
                 "moment": "^2.29.1",
+                "moment-timezone": "^0.5.34",
                 "pixelmatch": "^5.2.1",
                 "rollup": "^2.44.0",
                 "rollup-plugin-analyzer": "^4.0.0",
@@ -11743,6 +11744,18 @@
                 "node": "*"
             }
         },
+        "node_modules/moment-timezone": {
+            "version": "0.5.34",
+            "resolved": "https://registry.npmjs.org/moment-timezone/-/moment-timezone-0.5.34.tgz",
+            "integrity": "sha512-3zAEHh2hKUs3EXLESx/wsgw6IQdusOT8Bxm3D9UrHPQR7zlMmzwybC8zHEM1tQ4LJwP7fcxrWr8tuBg05fFCbg==",
+            "dev": true,
+            "dependencies": {
+                "moment": ">= 2.9.0"
+            },
+            "engines": {
+                "node": "*"
+            }
+        },
         "node_modules/move-concurrently": {
             "version": "1.0.1",
             "resolved": "https://registry.npmjs.org/move-concurrently/-/move-concurrently-1.0.1.tgz",
@@ -28426,6 +28439,15 @@
             "integrity": "sha512-kHmoybcPV8Sqy59DwNDY3Jefr64lK/by/da0ViFcuA4DH0vQg5Q6Ze5VimxkfQNSC+Mls/Kx53s7TjP1RhFEDQ==",
             "dev": true
         },
+        "moment-timezone": {
+            "version": "0.5.34",
+            "resolved": "https://registry.npmjs.org/moment-timezone/-/moment-timezone-0.5.34.tgz",
+            "integrity": "sha512-3zAEHh2hKUs3EXLESx/wsgw6IQdusOT8Bxm3D9UrHPQR7zlMmzwybC8zHEM1tQ4LJwP7fcxrWr8tuBg05fFCbg==",
+            "dev": true,
+            "requires": {
+                "moment": ">= 2.9.0"
+            }
+        },
         "move-concurrently": {
             "version": "1.0.1",
             "resolved": "https://registry.npmjs.org/move-concurrently/-/move-concurrently-1.0.1.tgz",
diff --git a/package.json b/package.json
index e56174eb9..ee472f639 100644
--- a/package.json
+++ b/package.json
@@ -87,6 +87,7 @@
         "luxon": "^1.26.0",
         "markdown-it-include": "^2.0.0",
         "moment": "^2.29.1",
+        "moment-timezone": "^0.5.34",
         "pixelmatch": "^5.2.1",
         "rollup": "^2.44.0",
         "rollup-plugin-analyzer": "^4.0.0",
diff --git a/test/index.js b/test/index.js
index 489fca0a7..8f1b7ced3 100644
--- a/test/index.js
+++ b/test/index.js
@@ -18,6 +18,10 @@ jasmine.fixture = {
 
 jasmine.triggerMouseEvent = triggerMouseEvent;
 
+// Set a fixed time zone (and, in particular, disable Daylight Saving Time) for
+// more stable test results.
+window.moment.tz.setDefault('Etc/UTC');
+
 beforeEach(function() {
   addMatchers();
 });
diff --git a/test/specs/scale.time.tests.js b/test/specs/scale.time.tests.js
index 4113d8a49..6e673157f 100644
--- a/test/specs/scale.time.tests.js
+++ b/test/specs/scale.time.tests.js
@@ -450,8 +450,11 @@ describe('Time scale tests', function() {
         datasets: [{
           xAxisID: 'x',
           data: [
-            {t: +new Date('2018-01-08 05:14:23.234'), y: 10},
-            {t: +new Date('2018-01-09 06:17:43.426'), y: 3}
+            // Normally (at least with the moment.js adapter), times would be in
+            // the user's local time zone.  To allow for more stable tests, our
+            // tests/index.js sets moment.js to use UTC; use `Z` here to match.
+            {t: +new Date('2018-01-08 05:14:23.234Z'), y: 10},
+            {t: +new Date('2018-01-09 06:17:43.426Z'), y: 3}
           ]
         }],
       },
@@ -1175,7 +1178,7 @@ describe('Time scale tests', function() {
           }
         });
 
-        // NOTE: built-in adapter uses moment
+        // NOTE: the test suite is configured to use moment
         var expected = {
           datetime: 'MMM D, YYYY, h:mm:ss a',
           millisecond: 'h:mm:ss.SSS a',
@@ -1213,7 +1216,7 @@ describe('Time scale tests', function() {
           }
         });
 
-        // NOTE: built-in adapter uses moment
+        // NOTE: the test suite is configured to use moment
         var expected = {
           datetime: 'MMM D, YYYY, h:mm:ss a',
           millisecond: 'foo',
-- 
2.47.2