feat(layout): plan 01 — tile engine + view registry

1 files changed, 80 insertions, 0 deletions

diff --git a/src/features/layout/logic/registry.test.ts b/src/features/layout/logic/registry.test.ts
new file mode 100644
index 0000000..443e50d
--- /dev/null
+++ b/src/features/layout/logic/registry.test.ts
@@ -0,0 +1,80 @@
+import type { Component } from "svelte";
+import { afterEach, describe, expect, it } from "vitest";
+import {
+  getView,
+  listPanelViews,
+  listViews,
+  registerView,
+  unregisterView,
+  type ViewRegistration,
+  viewRegistry,
+} from "./registry";
+
+const fakeComponent: Component = () => {
+  throw new Error("fixture component should never be constructed");
+};
+
+function registration(overrides?: Partial<ViewRegistration>): ViewRegistration {
+  return { id: "test-view", label: "Test View", component: fakeComponent, ...overrides };
+}
+
+const registeredIds = (): string[] => listViews().map((v) => v.id);
+
+afterEach(() => {
+  for (const id of registeredIds()) unregisterView(id);
+});
+
+describe("view registry", () => {
+  it("registers a view and exposes it via getView/listViews", () => {
+    registerView(registration());
+    expect(getView("test-view")?.label).toBe("Test View");
+    expect(registeredIds()).toContain("test-view");
+  });
+
+  it("throws loudly on a duplicate id", () => {
+    registerView(registration());
+    expect(() => registerView(registration({ label: "Other" }))).toThrow(/duplicate view id/);
+  });
+
+  it("normalizes panelEligible to true by default and respects false", () => {
+    registerView(registration({ id: "a" }));
+    registerView(registration({ id: "b", panelEligible: false }));
+    expect(getView("a")?.panelEligible).toBe(true);
+    expect(getView("b")?.panelEligible).toBe(false);
+    expect(listPanelViews().map((v) => v.id)).toContain("a");
+    expect(listPanelViews().map((v) => v.id)).not.toContain("b");
+  });
+
+  it("keeps pluginId when given", () => {
+    registerView(registration({ id: "plugin-view", pluginId: "my-plugin" }));
+    expect(getView("plugin-view")?.pluginId).toBe("my-plugin");
+  });
+
+  it("unregisterView removes the view (idempotent for unknown ids)", () => {
+    registerView(registration({ id: "gone" }));
+    unregisterView("gone");
+    expect(getView("gone")).toBeUndefined();
+    expect(() => unregisterView("never-registered")).not.toThrow();
+  });
+
+  it("is reactive: subscribers see registrations and unregistrations", () => {
+    const seen: string[][] = [];
+    const unsubscribe = viewRegistry.subscribe((views) => seen.push(views.map((v) => v.id)));
+    try {
+      registerView(registration({ id: "reactive-a" }));
+      registerView(registration({ id: "reactive-b" }));
+      unregisterView("reactive-a");
+    } finally {
+      unsubscribe();
+    }
+    expect(seen[0]).toEqual([]);
+    expect(seen.at(-1)).toEqual(["reactive-b"]);
+  });
+
+  it("preserves registration order in listViews", () => {
+    registerView(registration({ id: "z-first" }));
+    registerView(registration({ id: "a-second" }));
+    const ids = registeredIds();
+    expect(ids.indexOf("z-first")).toBeLessThan(ids.indexOf("a-second"));
+  });
+});