Fixed #19429 -- Applied linebreaksbr to read-only fields in inlines

Applied to inlines what ec9d6b1 did for main fieldsets.

django/contrib/admin/templates/admin/edit_inline/tabular.html

@@ -46,7 +46,7 @@ <h2>{{ inline_admin_formset.opts.verbose_name_plural|capfirst }}</h2>
             {% for field in line %}
               <td{% if field.field.name %} class="field-{{ field.field.name }}"{% endif %}>
               {% if field.is_readonly %}
-                  <p>{{ field.contents }}</p>
+                  <p>{{ field.contents|linebreaksbr }}</p>
               {% else %}
                   {{ field.field.errors.as_ul }}
                   {{ field.field }}

tests/regressiontests/admin_views/admin.py

@@ -346,7 +346,10 @@ class LinkInline(admin.TabularInline):
     model = Link
     extra = 1
 
-    readonly_fields = ("posted",)
+    readonly_fields = ("posted", "multiline")
+
+    def multiline(self, instance):
+        return "InlineMultiline\ntest\nstring"
 
 
 class SubPostInline(admin.TabularInline):

tests/regressiontests/admin_views/tests.py

@@ -3164,6 +3164,7 @@ def test_readonly_get(self):
 
         # Checks that multiline text in a readonly field gets <br /> tags
         self.assertContains(response, "Multiline<br />test<br />string")
+        self.assertContains(response, "InlineMultiline<br />test<br />string")
 
         self.assertContains(response,
             formats.localize(datetime.date.today() - datetime.timedelta(days=7))