1 files changed, 46 insertions, 0 deletions
diff --git a/packages/app/src/theme-preload.test.ts b/packages/app/src/theme-preload.test.ts
new file mode 100644
index 000000000..00d7da239
--- /dev/null
+++ b/packages/app/src/theme-preload.test.ts
@@ -0,0 +1,46 @@
+import { beforeEach, describe, expect, test } from "bun:test"
+
+const src = await Bun.file(new URL("../public/oc-theme-preload.js", import.meta.url)).text()
+
+const run = () => Function(src)()
+
+beforeEach(() => {
+  document.head.innerHTML = ""
+  document.documentElement.removeAttribute("data-theme")
+  document.documentElement.removeAttribute("data-color-scheme")
+  localStorage.clear()
+  Object.defineProperty(window, "matchMedia", {
+    value: () =>
+      ({
+        matches: false,
+      }) as MediaQueryList,
+    configurable: true,
+  })
+})
+
+describe("theme preload", () => {
+  test("migrates legacy oc-1 to oc-2 before mount", () => {
+    localStorage.setItem("opencode-theme-id", "oc-1")
+    localStorage.setItem("opencode-theme-css-light", "--background-base:#fff;")
+    localStorage.setItem("opencode-theme-css-dark", "--background-base:#000;")
+
+    run()
+
+    expect(document.documentElement.dataset.theme).toBe("oc-2")
+    expect(document.documentElement.dataset.colorScheme).toBe("light")
+    expect(localStorage.getItem("opencode-theme-id")).toBe("oc-2")
+    expect(localStorage.getItem("opencode-theme-css-light")).toBeNull()
+    expect(localStorage.getItem("opencode-theme-css-dark")).toBeNull()
+    expect(document.getElementById("oc-theme-preload")).toBeNull()
+  })
+
+  test("keeps cached css for non-default themes", () => {
+    localStorage.setItem("opencode-theme-id", "nightowl")
+    localStorage.setItem("opencode-theme-css-light", "--background-base:#fff;")
+
+    run()
+
+    expect(document.documentElement.dataset.theme).toBe("nightowl")
+    expect(document.getElementById("oc-theme-preload")?.textContent).toContain("--background-base:#fff;")
+  })
+})