Add subevent location to order info in emails (#2354)

src/pretix/base/templates/pretixbase/email/order_details.html

@@ -1,5 +1,6 @@
 {% load eventurl %}
 {% load i18n %}
+{% load oneline %}
 
 {% if position %}
     <div class="order-info">
@@ -107,6 +108,10 @@
                                         {% if event.settings.show_times %}
                                             {{ groupkey.2.date_from|date:"TIME_FORMAT" }}
                                         {% endif %}
+                                        {% if groupkey.2.location %}
+                                            <br>
+                                            {{ groupkey.2.location|oneline }}
+                                        {% endif %}
                                     {% endif %}
                                     {% if groupkey.3 %} {# attendee name #}
                                         <br>

src/pretix/base/templatetags/oneline.py

@@ -0,0 +1,29 @@
+#
+# This file is part of pretix (Community Edition).
+#
+# Copyright (C) 2014-2020 Raphael Michel and contributors
+# Copyright (C) 2020-2021 rami.io GmbH and contributors
+#
+# This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General
+# Public License as published by the Free Software Foundation in version 3 of the License.
+#
+# ADDITIONAL TERMS APPLY: Pursuant to Section 7 of the GNU Affero General Public License, additional terms are
+# applicable granting you additional permissions and placing additional restrictions on your usage of this software.
+# Please refer to the pretix LICENSE file to obtain the full terms applicable to this work. If you did not receive
+# this file, see <https://pretix.eu/about/en/license>.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
+# warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Affero General Public License along with this program.  If not, see
+# <https://www.gnu.org/licenses/>.
+#
+from django import template
+
+register = template.Library()
+
+
+@register.simple_tag
+def oneline(value):
+    return ', '.join([l.strip() for l in value.splitlines() if l and l.strip()])