Fixed #30425 -- Handled jinja2.TemplateSyntaxError when rendering a template.

Jinja raises jinja2.TemplateSyntaxError in render() not in
get_template() when it's in an included template.

1 files changed, 24 insertions, 7 deletions

diff --git a/django/template/backends/jinja2.py b/django/template/backends/jinja2.py
index ac7c05895c..d1e5217b51 100644
--- a/django/template/backends/jinja2.py
+++ b/django/template/backends/jinja2.py
@@ -1,3 +1,5 @@
+from pathlib import Path
+
 import jinja2
 
 from django.conf import settings
@@ -68,7 +70,12 @@ class Template:
             context['csrf_token'] = csrf_token_lazy(request)
             for context_processor in self.backend.template_context_processors:
                 context.update(context_processor(request))
-        return self.template.render(context)
+        try:
+            return self.template.render(context)
+        except jinja2.TemplateSyntaxError as exc:
+            new = TemplateSyntaxError(exc.args)
+            new.template_debug = get_exception_info(exc)
+            raise new from exc
 
 
 class Origin:
@@ -88,12 +95,22 @@ def get_exception_info(exception):
     """
     context_lines = 10
     lineno = exception.lineno
-    lines = list(enumerate(exception.source.strip().split("\n"), start=1))
-    during = lines[lineno - 1][1]
-    total = len(lines)
-    top = max(0, lineno - context_lines - 1)
-    bottom = min(total, lineno + context_lines)
-
+    source = exception.source
+    if source is None:
+        exception_file = Path(exception.filename)
+        if exception_file.exists():
+            with open(exception_file, 'r') as fp:
+                source = fp.read()
+    if source is not None:
+        lines = list(enumerate(source.strip().split('\n'), start=1))
+        during = lines[lineno - 1][1]
+        total = len(lines)
+        top = max(0, lineno - context_lines - 1)
+        bottom = min(total, lineno + context_lines)
+    else:
+        during = ''
+        lines = []
+        total = top = bottom = 0
     return {
         'name': exception.filename,
         'message': exception.message,