Patch TemplateProxy to restore compatibility with template_partials (#1328)

Co-authored-by: EmilStenstrom <224130+EmilStenstrom@users.noreply.github.com>
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: Juro Oravec <juraj.oravec.josefson@gmail.com>

tests/test_integration_template_partials.py

@@ -0,0 +1,84 @@
+"""
+Tests for template_partials integration with django-components.
+
+See https://github.com/django-components/django-components/issues/1327
+and https://github.com/django-components/django-components/issues/1323.
+
+This file can be deleted after Django 5.2 reached end of life.
+See https://github.com/django-components/django-components/issues/1323#issuecomment-3163478287.
+"""
+
+from typing import NamedTuple
+
+import pytest
+from django.shortcuts import render
+from django.http import HttpRequest
+
+from django_components import Component, register
+from django_components.testing import djc_test
+from .testutils import setup_test_config
+
+try:
+    from template_partials.templatetags.partials import TemplateProxy
+except ImportError:
+    TemplateProxy = None
+
+
+setup_test_config(components={"autodiscover": False})
+
+
+# See https://github.com/django-components/django-components/issues/1323#issuecomment-3156654329
+@djc_test(
+    django_settings={"INSTALLED_APPS": ("template_partials", "django_components", "tests.test_app")}
+)
+class TestTemplatePartialsIntegration:
+    @pytest.mark.skipif(TemplateProxy is None, reason="template_partials not available")
+    def test_render_partial(self):
+        @register("calendar")
+        class Calendar(Component):
+            template = """
+                <div class="calendar-component">
+                    <div>Today's date is <span>{{ date }}</span></div>
+                </div>
+            """
+            css = """
+                .calendar-component { width: 200px; background: pink; }
+                .calendar-component span { font-weight: bold; }
+            """
+            js = """
+                (function(){
+                    if (document.querySelector(".calendar-component")) {
+                        document.querySelector(".calendar-component").onclick = function(){ alert("Clicked calendar!"); };
+                    }
+                })()
+            """  # noqa: E501
+
+            class Kwargs(NamedTuple):
+                date: str
+
+            def get_template_data(self, args, kwargs: Kwargs, slots, context):
+                return {
+                    "date": kwargs.date,
+                }
+
+        # NOTE: When a full template is rendered (without the `#` syntax), the output should be as usual.
+        request = HttpRequest()
+        result = render(request, "integration_template_partials.html")
+        content = result.content
+
+        assert b"<!-- _RENDERED" not in content
+        assert b"width: 200px;" in content
+        assert b'alert("Clicked calendar!")' in content
+
+        # NOTE: When a partial is rendered with the `#` syntax, what *actually*
+        # gets rendered is `TemplateProxy` from template_partials, instead of Django's own `Template` class.
+        # Hence, the monkeypatching that we've done on the Template class does NOT apply to TemplateProxy.
+        # So we want to check that the result HAS its CSS/JS processed, which means that the monkeypatching
+        # works as expected.
+        request2 = HttpRequest()
+        result2 = render(request2, "integration_template_partials.html#test___partial")
+        content2 = result2.content
+
+        assert b"<!-- _RENDERED" not in content2
+        assert b"width: 200px;" in content2
+        assert b'alert("Clicked calendar!")' in content2