From 05054f1e6008b9dcd2699e3f49b583195fc99363 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=89tienne=20T=C3=A9treault-Pinard?= <etienne@plot.ly>
Date: Mon, 23 Dec 2019 17:27:38 -0500
Subject: [PATCH 1/2] add fallback in trace calendar getter in
 Histogram.crossTraceCalc

... so that when the Calendars module isn't registered (thus making
    `_fullData[i].(x|y)calendar` undefined), we're still
    able to group traces in the correct bin groups
---
 src/traces/histogram/cross_trace_defaults.js |  2 +-
 test/jasmine/tests/histogram_test.js         | 30 ++++++++++++++++++++
 2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/src/traces/histogram/cross_trace_defaults.js b/src/traces/histogram/cross_trace_defaults.js
index c699cf7d50c..0fbfc4e6570 100644
--- a/src/traces/histogram/cross_trace_defaults.js
+++ b/src/traces/histogram/cross_trace_defaults.js
@@ -55,7 +55,7 @@ module.exports = function crossTraceDefaults(fullData, fullLayout) {
         if(!groupName) groupName = fallbackGroupName;
 
         var axType = getAxisType(traceOut, binDir);
-        var calendar = traceOut[binDir + 'calendar'];
+        var calendar = traceOut[binDir + 'calendar'] || '';
         var binOpts = allBinOpts[groupName];
         var needsNewItem = true;
 
diff --git a/test/jasmine/tests/histogram_test.js b/test/jasmine/tests/histogram_test.js
index 97bd6446205..9166efee1cc 100644
--- a/test/jasmine/tests/histogram_test.js
+++ b/test/jasmine/tests/histogram_test.js
@@ -1,6 +1,7 @@
 var Plotly = require('@lib/index');
 var Plots = require('@src/plots/plots');
 var Lib = require('@src/lib');
+var Registry = require('@src/registry');
 var setConvert = require('@src/plots/cartesian/set_convert');
 
 var supplyDefaults = require('@src/traces/histogram/defaults');
@@ -478,6 +479,35 @@ describe('Test histogram', function() {
             );
         });
 
+        it('should not group traces across different calendars when the calendar module is not registered', function() {
+            var original = Registry.getComponentMethod;
+            var cnt = 0;
+
+            spyOn(Registry, 'getComponentMethod').and.callFake(function() {
+                if(arguments[0] === 'calendars') {
+                    cnt++;
+                    return Lib.noop;
+                } else {
+                    return original.call(arguments);
+                }
+            });
+
+            gd = {
+                data: [
+                    {uid: 'a', type: 'histogram', x: [1, 3]},
+                    {uid: 'b', type: 'histogram', x: [1, 20]}
+                ],
+                layout: {barmode: 'stack'}
+            };
+            supplyAllDefaults(gd);
+
+            _assert('', [
+                ['xyx', [0, 1]]
+            ]);
+
+            expect(cnt).toBe(3, '# of Registry.getComponentMethod calls for *calendars* methods');
+        });
+
         it('should force traces that "have to match" to have same bingroup (alignmentgroup case)', function() {
             var traces;
 

From ee9425153f753f42677be5bf1fefbca55119e7b0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=89tienne=20T=C3=A9treault-Pinard?= <etienne@plot.ly>
Date: Mon, 23 Dec 2019 17:48:47 -0500
Subject: [PATCH 2/2] fixup test description

---
 test/jasmine/tests/histogram_test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/jasmine/tests/histogram_test.js b/test/jasmine/tests/histogram_test.js
index 9166efee1cc..df31aa0a304 100644
--- a/test/jasmine/tests/histogram_test.js
+++ b/test/jasmine/tests/histogram_test.js
@@ -479,7 +479,7 @@ describe('Test histogram', function() {
             );
         });
 
-        it('should not group traces across different calendars when the calendar module is not registered', function() {
+        it('should attempt to group traces when the *calendars* module is not registered', function() {
             var original = Registry.getComponentMethod;
             var cnt = 0;