Fixed #26306 -- Fixed memory leak in cached template loader.

1 files changed, 14 insertions, 3 deletions

diff --git a/django/template/backends/django.py b/django/template/backends/django.py
index cc795aae1c..afe1a7cd23 100644
--- a/django/template/backends/django.py
+++ b/django/template/backends/django.py
@@ -68,13 +68,24 @@ class Template(object):
             reraise(exc, self.backend)
 
 
-def reraise(exc, backend):
+def copy_exception(exc, backend=None):
     """
-    Reraise TemplateDoesNotExist while maintaining template debug information.
+    Create a new TemplateDoesNotExist. Preserve its declared attributes and
+    template debug data but discard __traceback__, __context__, and __cause__
+    to make this object suitable for keeping around (in a cache, for example).
     """
-    new = exc.__class__(*exc.args, tried=exc.tried, backend=backend)
+    backend = backend or exc.backend
+    new = exc.__class__(*exc.args, tried=exc.tried, backend=backend, chain=exc.chain)
     if hasattr(exc, 'template_debug'):
         new.template_debug = exc.template_debug
+    return new
+
+
+def reraise(exc, backend):
+    """
+    Reraise TemplateDoesNotExist while maintaining template debug information.
+    """
+    new = copy_exception(exc, backend)
     six.reraise(exc.__class__, new, sys.exc_info()[2])