1 files changed, 89 insertions, 0 deletions
diff --git a/src/features/settings/ui/ChatLimitField.test.ts b/src/features/settings/ui/ChatLimitField.test.ts
new file mode 100644
index 0000000..8f8da25
--- /dev/null
+++ b/src/features/settings/ui/ChatLimitField.test.ts
@@ -0,0 +1,89 @@
+import { render, screen } from "@testing-library/svelte";
+import userEvent from "@testing-library/user-event";
+import { describe, expect, it } from "vitest";
+import type { ChatLimitSaveResult } from "../logic/view-model";
+import ChatLimitField from "./ChatLimitField.svelte";
+
+// A fake save that resolves ok with the value it was given.
+function fakeSave(): {
+  saves: number[];
+  last: number | null;
+  impl: (value: number) => Promise<ChatLimitSaveResult>;
+} {
+  const saves: number[] = [];
+  return {
+    saves,
+    last: null,
+    impl: async (value: number) => {
+      saves.push(value);
+      return { ok: true, chatLimit: value };
+    },
+  };
+}
+
+describe("ChatLimitField", () => {
+  it("seeds the input from the persisted limit and disables Set while unchanged", () => {
+    render(ChatLimitField, { props: { chatLimit: 256, save: fakeSave().impl } });
+    expect(screen.getByLabelText("Chat limit")).toHaveValue("256");
+    expect(screen.getByRole("button", { name: "Set" })).toBeDisabled();
+  });
+
+  it("enables Set when the typed value differs (regression: number-binding coercion)", async () => {
+    const user = userEvent.setup();
+    const save = fakeSave();
+    render(ChatLimitField, { props: { chatLimit: 256, save: save.impl } });
+
+    const input = screen.getByLabelText("Chat limit");
+    await user.clear(input);
+    await user.type(input, "10");
+
+    expect(screen.getByRole("button", { name: "Set" })).toBeEnabled();
+  });
+
+  it("keeps Set disabled for non-numeric input", async () => {
+    const user = userEvent.setup();
+    const save = fakeSave();
+    render(ChatLimitField, { props: { chatLimit: 256, save: save.impl } });
+
+    const input = screen.getByLabelText("Chat limit");
+    await user.clear(input);
+    await user.type(input, "abc");
+
+    expect(screen.getByRole("button", { name: "Set" })).toBeDisabled();
+  });
+
+  it("clicking Set calls save with the parsed value and shows the confirmation", async () => {
+    const user = userEvent.setup();
+    const save = fakeSave();
+    const { rerender } = render(ChatLimitField, {
+      props: { chatLimit: 256, save: save.impl },
+    });
+
+    const input = screen.getByLabelText("Chat limit");
+    await user.clear(input);
+    await user.type(input, "50");
+    await user.click(screen.getByRole("button", { name: "Set" }));
+
+    expect(save.saves).toEqual([50]);
+    // In the real app the reactive `chatLimit` prop updates to the saved value
+    // (the store sets it synchronously), which clears `dirty` and reveals the
+    // "Saved" badge. Rerender simulates that propagation.
+    rerender({ chatLimit: 50, save: save.impl });
+    expect(screen.getByText(/Saved/i)).toBeInTheDocument();
+  });
+
+  it("clamps a below-floor value when saving", async () => {
+    const user = userEvent.setup();
+    const save = fakeSave();
+    render(ChatLimitField, { props: { chatLimit: 256, save: save.impl } });
+
+    const input = screen.getByLabelText("Chat limit");
+    await user.clear(input);
+    await user.type(input, "5"); // clamps to MIN (10)
+    await user.click(screen.getByRole("button", { name: "Set" }));
+
+    // The save port receives the clamped value (the view-model clamps before save).
+    expect(save.saves).toEqual([10]);
+    expect(input).toHaveValue("10");
+  });
+});