complete performance and reliability follow-ups

packages/styles/test/theme.test.ts

@@ -5,6 +5,8 @@ import {
   resolveThemeConfig,
   resolveThemeName,
   renderThemeCss,
+  renderActiveThemeCss,
+  activeThemeCssHref,
   renderThemeRuntime,
 } from "../src/index.ts";
 
@@ -85,6 +87,17 @@ test("renderThemeCss emits :root + per-theme blocks and --wire-* vars", () => {
   expect(css).toContain("font-family:var(--wire-font-sans");
 });
 
+test("active theme CSS contains only the selected theme and accent", () => {
+  const theme = resolveThemeConfig({ default: "dark", palette: "rose" });
+  const full = renderThemeCss(theme);
+  const active = renderActiveThemeCss(theme, "dark", "rose");
+  expect(active).toContain(":root{");
+  expect(active).not.toContain('[data-theme="light"]');
+  expect(active.length).toBeLessThan(full.length / 4);
+  expect(activeThemeCssHref("dark", "rose")).toBe("/__wrnexus/theme/dark/rose.css");
+  expect(() => renderActiveThemeCss(theme, "missing")).toThrow("Unknown theme");
+});
+
 test("renderThemeRuntime bakes the theme names for cycling", () => {
   const t = resolveThemeConfig();
   const js = renderThemeRuntime(t);