Allow bundles to be rendered after "theme" and "custom" bundles.

Products/CMFPlone/resources/browser/resource.py

@@ -94,6 +94,11 @@ def update(self):
         # collect names
         js_names = [name for name, rec in records.items() if rec.jscompilation]
         css_names = [name for name, rec in records.items() if rec.csscompilation]
+        # Allow bundles to have "theme" resp. "theme" and "custom" as dependency
+        # so that bundles can be rendered after theme and custom resources.
+        js_names += ["theme"]
+        css_names += ["theme", "custom"]
+
         all_names = [
             name
             for name, rec in records.items()

Products/CMFPlone/tests/testResourceRegistries.py

@@ -165,6 +165,34 @@ def test_bundle_depends(self):
         results = view.render()
         self.assertIn("http://foo.bar/foobar.js", results)
 
+    def test_bundle_depends_theme(self):
+        from lxml import etree
+
+        # Bluntly set a JavaScript file for the theme to ensure the "theme"
+        # dependency exists.
+        from plone.app.theming.utils import theming_policy
+        theme = theming_policy(self.layer["request"]).get_theme()
+        theme.production_js = "theme.js"
+
+        bundle = self._make_test_bundle()
+
+        # This bundle should depend on "theme"
+        bundle.depends = "theme"
+
+        view = ScriptsView(self.app, self.app.REQUEST, None, None)
+        view.update()
+        results = view.render()
+
+        parser = etree.HTMLParser()
+        parsed = etree.fromstring(results, parser)
+        scripts = parsed.xpath("//script")
+
+        # The last element is our script bundle depending on "theme"
+        self.assertEqual("http://foo.bar/foobar.js", scripts[-1].attrib["src"])
+
+        # The second last element is the theme javascript itself.
+        self.assertIn("theme.js", scripts[-2].attrib["src"])
+
     def test_bundle_depends_on_multiple(self):
         bundle = self._make_test_bundle()
         bundle.depends = "plone,eventedit"
@@ -217,6 +245,19 @@ def test_relative_uri_resource(self):
 
 
 class TestStylesViewlet(PloneTestCase.PloneTestCase):
+    def _make_test_bundle(self):
+        registry = getUtility(IRegistry)
+
+        bundles = registry.collectionOfInterface(
+            IBundleRegistry, prefix="plone.bundles"
+        )
+        bundle = bundles.add("foobar")
+        bundle.name = "foobar"
+        bundle.jscompilation = "http://foo.bar/foobar.js"
+        bundle.csscompilation = "http://foo.bar/foobar.css"
+        bundle.resources = ["foobar"]
+        return bundle
+
     def test_styles_viewlet(self):
         styles = StylesView(self.layer["portal"], self.layer["request"], None)
         styles.update()
@@ -323,6 +364,34 @@ def test_remove_bundle_on_request_with_subrequest(self):
         result = scripts.render()
         self.assertNotIn("http://test.foo/test.min.js", result)
 
+    def test_bundle_depends_theme(self):
+        from lxml import etree
+
+        # Bluntly set a JavaScript file for the theme to ensure the "theme"
+        # dependency exists.
+        from plone.app.theming.utils import theming_policy
+        theme = theming_policy(self.layer["request"]).get_theme()
+        theme.production_css = "theme.css"
+
+        bundle = self._make_test_bundle()
+
+        # This bundle should depend on "theme"
+        bundle.depends = "theme"
+
+        view = StylesView(self.app, self.app.REQUEST, None, None)
+        view.update()
+        results = view.render()
+
+        parser = etree.HTMLParser()
+        parsed = etree.fromstring(results, parser)
+        styles = parsed.xpath("//link")
+
+        # The last element is our script bundle depending on "theme"
+        self.assertEqual("http://foo.bar/foobar.css", styles[-1].attrib["href"])
+
+        # The second last element is the theme javascript itself.
+        self.assertIn("theme.css", styles[-2].attrib["href"])
+
 
 class TestExpressions(PloneTestCase.PloneTestCase):
     def logout(self):

news/4054.feature

@@ -0,0 +1,11 @@
+Allow bundles to be rendered after "theme" and "custom" bundles.
+
+Bundles can now depend on the automatically added "theme" and "custom" bundles
+from plone.app.theming and be rendered after those (e.g. after the
+plonetheme.barceloneta CSS).
+
+This allows to override a theme with custom CSS from a bundle instead of having
+to add the CSS customizations to the registry via the "custom_css" settings.
+As a consequence, theme customization can now be done in the filesystem in
+ordinary CSS files instead of being bound to a time consuming workflow which
+involces upgrading the registry after every change.