add extra_context to NavGroup and NavItem (#34)

Author: joshuadavidthomas

CHANGELOG.md

@@ -18,10 +18,18 @@ and this project attempts to adhere to [Semantic Versioning](https://semver.org/
 
 ## [Unreleased]
 
+### Added
+
+- `NavGroup` and `NavItem` now has a new `extra_context` attribute. This allows for passing additional context to the template when rendering the navigation, either via the extra attribute (`item.foo`) or the `extra_context` attribute itself (`item.extra_context.foo`).
+
 ### Changed
 
 - Now using v2024.13 of `django-twc-package`.
 
+### Fixed
+
+- `RenderedNavItem.items` property now correctly returns a list of `RenderedNavItem` objects, rather than a list of `NavItem` objects. This fixes a bug where the properties that should be available (e.g. `active`, `url`, etc.) were not available when iterating over the `RenderedNavItem.items` list if the item was a `NavGroup` object with child items.
+
 ## [0.2.0]
 
 ### Added

src/django_simple_nav/nav.py

@@ -2,6 +2,7 @@
 
 from dataclasses import dataclass
 from dataclasses import field
+from typing import Any
 
 from django.http import HttpRequest
 from django.template.loader import render_to_string
@@ -38,29 +39,43 @@ class NavGroup:
     items: list[NavGroup | NavItem]
     url: str | None = None
     permissions: list[str] = field(default_factory=list)
+    extra_context: dict[str, Any] = field(default_factory=dict)
 
 
 @dataclass(frozen=True)
 class NavItem:
     title: str
     url: str
     permissions: list[str] = field(default_factory=list)
+    extra_context: dict[str, Any] = field(default_factory=dict)
 
 
 @dataclass(frozen=True)
 class RenderedNavItem:
     item: NavItem | NavGroup
     request: HttpRequest
 
+    def __getattr__(self, name: str) -> Any:
+        if name == "extra_context":
+            return self.item.extra_context
+        elif hasattr(self.item, name):
+            return getattr(self.item, name)
+        else:
+            try:
+                return self.item.extra_context[name]
+            except KeyError as err:
+                msg = f"{self.item!r} object has no attribute {name!r}"
+                raise AttributeError(msg) from err
+
     @property
     def title(self) -> str:
         return mark_safe(self.item.title)
 
     @property
-    def items(self) -> list[NavGroup | NavItem] | None:
+    def items(self) -> list[RenderedNavItem] | None:
         if not isinstance(self.item, NavGroup):
             return None
-        return self.item.items
+        return [RenderedNavItem(item, self.request) for item in self.item.items]
 
     @property
     def url(self) -> str:

tests/test_nav.py

@@ -6,6 +6,9 @@
 from django.utils.module_loading import import_string
 from model_bakery import baker
 
+from django_simple_nav.nav import NavGroup
+from django_simple_nav.nav import NavItem
+from django_simple_nav.nav import RenderedNavItem
 from tests.navs import DummyNav
 from tests.utils import count_anchors
 
@@ -96,3 +99,89 @@ def test_nav_render_from_request_with_template_name(req):
     rendered_template = DummyNav.render_from_request(req, "tests/alternate.html")
 
     assert "This is an alternate template." in rendered_template
+
+
+def test_extra_context(req):
+    item = NavItem(
+        title="Test",
+        url="/test/",
+        extra_context={"foo": "bar"},
+    )
+
+    rendered_item = RenderedNavItem(item, req)
+
+    assert rendered_item.foo == "bar"
+
+
+def test_extra_context_with_no_extra_context(req):
+    item = NavItem(
+        title="Test",
+        url="/test/",
+    )
+
+    rendered_item = RenderedNavItem(item, req)
+
+    with pytest.raises(AttributeError):
+        assert rendered_item.foo == "bar"
+
+
+def test_extra_context_shadowing(req):
+    item = NavItem(
+        title="Test",
+        url="/test/",
+        extra_context={"title": "Shadowed"},
+    )
+
+    rendered_item = RenderedNavItem(item, req)
+
+    assert rendered_item.title == "Test"
+
+
+def test_extra_context_iteration(req):
+    item = NavItem(
+        title="Test",
+        url="/test/",
+        extra_context={"foo": "bar", "baz": "qux"},
+    )
+
+    rendered_item = RenderedNavItem(item, req)
+
+    assert rendered_item.extra_context == {"foo": "bar", "baz": "qux"}
+    for key, value in rendered_item.extra_context.items():
+        assert getattr(rendered_item, key) == value
+
+
+def test_extra_context_builtins(req):
+    item = NavGroup(
+        title="Test",
+        items=[
+            NavItem(
+                title="Test",
+                url="/test/",
+                permissions=["is_staff"],
+                extra_context={"foo": "bar"},
+            ),
+        ],
+        url="/test/",
+        permissions=["is_staff"],
+        extra_context={"baz": "qux"},
+    )
+
+    rendered_item = RenderedNavItem(item, req)
+
+    assert rendered_item.title == "Test"
+    assert rendered_item.url == "/test/"
+    assert rendered_item.permissions == ["is_staff"]
+    assert rendered_item.extra_context == {"baz": "qux"}
+    assert rendered_item.baz == "qux"
+
+    assert rendered_item.items is not None
+    assert len(rendered_item.items) == 1
+
+    rendered_group_item = rendered_item.items[0]
+
+    assert rendered_group_item.title == "Test"
+    assert rendered_group_item.url == "/test/"
+    assert rendered_group_item.permissions == ["is_staff"]
+    assert rendered_group_item.extra_context == {"foo": "bar"}
+    assert rendered_group_item.foo == "bar"