test(coverage): bootstrap vitest unit infra and add tests at 90%+ per file (#1245) (#1269)

* test(coverage): bootstrap vitest unit infra and add tests at 90%+ per file (#1245)

Establishes the unit-test runtime AGENTS.md mandates: a vitest "unit"
project alongside the existing storybook project, RTL + jest-dom +
happy-dom, a Mantine-aware render helper, and a 90%-line per-file
coverage gate enforced by CI. Adds 66 test files covering all 62
components under elements/groups/screens/views, plus core/mcp and
clients/web/src/utils. Total: 577 tests, 98.7% line coverage globally.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* test(coverage): address PR #1269 review feedback

- AGENTS.md: correct coverage gate description (lines ≥ 90, statements ≥ 85,
  functions ≥ 80, branches ≥ 50) with rationale for the relaxed branch
  threshold
- InspectorView.test.tsx: document what the Math.random() mock values
  (0.1 / 0.99) control vs. STUB_SUCCESS_RATE in InspectorView.tsx
- vite.config.ts / tsconfig.test.json: drop unused `globals: true` and the
  `vitest/globals` type now that every test file imports describe/it/expect/vi
  explicitly; manual `afterEach(cleanup)` in setup.ts remains required because
  testing-library auto-cleanup relies on globalThis.afterEach

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

clients/web/src/components/groups/SamplingRequestPanel/SamplingRequestPanel.test.tsx

@@ -0,0 +1,238 @@
+import { describe, it, expect, vi } from "vitest";
+import userEvent from "@testing-library/user-event";
+import type {
+  CreateMessageRequestParams,
+  CreateMessageResult,
+} from "@modelcontextprotocol/sdk/types.js";
+import { renderWithMantine, screen } from "../../../test/renderWithMantine";
+import { SamplingRequestPanel } from "./SamplingRequestPanel";
+
+const simpleRequest: CreateMessageRequestParams = {
+  messages: [
+    {
+      role: "user",
+      content: { type: "text", text: "What is the capital of France?" },
+    },
+  ],
+  maxTokens: 1024,
+};
+
+const fullRequest: CreateMessageRequestParams = {
+  messages: [
+    {
+      role: "user",
+      content: { type: "text", text: "Write a haiku about programming." },
+    },
+  ],
+  maxTokens: 2048,
+  modelPreferences: {
+    hints: [{ name: "claude-sonnet-4" }, { name: "gpt-4" }],
+    costPriority: 0.2,
+    speedPriority: 0.5,
+    intelligencePriority: 0.9,
+  },
+  stopSequences: ["END"],
+  temperature: 0.7,
+  includeContext: "thisServer",
+};
+
+const blankDraft: CreateMessageResult = {
+  role: "assistant",
+  model: "claude-sonnet-4-20250514",
+  content: { type: "text", text: "" },
+};
+
+const imageDraft: CreateMessageResult = {
+  role: "assistant",
+  model: "claude-sonnet-4-20250514",
+  content: { type: "image", data: "abc", mimeType: "image/png" },
+};
+
+const baseProps = {
+  onResultChange: vi.fn(),
+  onAutoRespond: vi.fn(),
+  onSend: vi.fn(),
+  onReject: vi.fn(),
+};
+
+describe("SamplingRequestPanel", () => {
+  it("renders the helper text and message section", () => {
+    renderWithMantine(
+      <SamplingRequestPanel
+        {...baseProps}
+        request={simpleRequest}
+        draftResult={blankDraft}
+      />,
+    );
+    expect(
+      screen.getByText("The server is requesting an LLM completion."),
+    ).toBeInTheDocument();
+    expect(screen.getByText("Messages:")).toBeInTheDocument();
+    expect(
+      screen.getByText('"What is the capital of France?"'),
+    ).toBeInTheDocument();
+  });
+
+  it("renders 'not specified' for missing optional params", () => {
+    renderWithMantine(
+      <SamplingRequestPanel
+        {...baseProps}
+        request={{ messages: [] } as never}
+        draftResult={blankDraft}
+      />,
+    );
+    expect(screen.getByText("Max Tokens: not specified")).toBeInTheDocument();
+    expect(
+      screen.getByText("Stop Sequences: not specified"),
+    ).toBeInTheDocument();
+    expect(screen.getByText("Temperature: not specified")).toBeInTheDocument();
+  });
+
+  it("renders model preferences with hints, priorities, and includeContext", () => {
+    renderWithMantine(
+      <SamplingRequestPanel
+        {...baseProps}
+        request={fullRequest}
+        draftResult={blankDraft}
+      />,
+    );
+    expect(screen.getByText("Model Preferences:")).toBeInTheDocument();
+    expect(screen.getByText("claude-sonnet-4")).toBeInTheDocument();
+    expect(screen.getByText("gpt-4")).toBeInTheDocument();
+    expect(screen.getByText("Cost Priority: low (0.2)")).toBeInTheDocument();
+    expect(
+      screen.getByText("Speed Priority: medium (0.5)"),
+    ).toBeInTheDocument();
+    expect(
+      screen.getByText("Intelligence Priority: high (0.9)"),
+    ).toBeInTheDocument();
+    expect(screen.getByText("Max Tokens: 2048")).toBeInTheDocument();
+    expect(screen.getByText('Stop Sequences: ["END"]')).toBeInTheDocument();
+    expect(screen.getByText("Temperature: 0.7")).toBeInTheDocument();
+    expect(screen.getByText("Include Context:")).toBeInTheDocument();
+    expect(screen.getByText("thisServer")).toBeInTheDocument();
+  });
+
+  it("does not render preferences container when modelPreferences is absent", () => {
+    renderWithMantine(
+      <SamplingRequestPanel
+        {...baseProps}
+        request={simpleRequest}
+        draftResult={blankDraft}
+      />,
+    );
+    expect(screen.queryByText("Model Preferences:")).not.toBeInTheDocument();
+  });
+
+  it("does not render Hints row when hints are absent", () => {
+    renderWithMantine(
+      <SamplingRequestPanel
+        {...baseProps}
+        request={{
+          ...simpleRequest,
+          modelPreferences: { costPriority: 0.5 },
+        }}
+        draftResult={blankDraft}
+      />,
+    );
+    expect(screen.getByText("Model Preferences:")).toBeInTheDocument();
+    expect(screen.queryByText("Hints:")).not.toBeInTheDocument();
+  });
+
+  it("renders the response textarea pre-populated for text drafts", () => {
+    const filledDraft: CreateMessageResult = {
+      ...blankDraft,
+      content: { type: "text", text: "filled draft" },
+    };
+    renderWithMantine(
+      <SamplingRequestPanel
+        {...baseProps}
+        request={simpleRequest}
+        draftResult={filledDraft}
+      />,
+    );
+    expect(screen.getByDisplayValue("filled draft")).toBeInTheDocument();
+  });
+
+  it("renders an empty textarea for non-text draft content", () => {
+    renderWithMantine(
+      <SamplingRequestPanel
+        {...baseProps}
+        request={simpleRequest}
+        draftResult={imageDraft}
+      />,
+    );
+    const textarea = screen.getByRole("textbox", {
+      name: "",
+    }) as HTMLTextAreaElement;
+    expect(textarea.value).toBe("");
+  });
+
+  it("invokes onResultChange when typing into the response textarea", async () => {
+    const user = userEvent.setup();
+    const onResultChange = vi.fn();
+    renderWithMantine(
+      <SamplingRequestPanel
+        {...baseProps}
+        request={simpleRequest}
+        draftResult={blankDraft}
+        onResultChange={onResultChange}
+      />,
+    );
+    const textareas = screen.getAllByRole("textbox");
+    await user.type(textareas[0], "x");
+    expect(onResultChange).toHaveBeenCalled();
+    const last = onResultChange.mock.calls.at(-1)?.[0];
+    expect(last.content).toEqual({ type: "text", text: "x" });
+  });
+
+  it("invokes onResultChange when typing into the model input", async () => {
+    const user = userEvent.setup();
+    const onResultChange = vi.fn();
+    renderWithMantine(
+      <SamplingRequestPanel
+        {...baseProps}
+        request={simpleRequest}
+        draftResult={blankDraft}
+        onResultChange={onResultChange}
+      />,
+    );
+    await user.type(screen.getByLabelText("Model Used"), "x");
+    expect(onResultChange).toHaveBeenCalled();
+  });
+
+  it("invokes onAutoRespond, onSend, and onReject when their buttons are clicked", async () => {
+    const user = userEvent.setup();
+    const onAutoRespond = vi.fn();
+    const onSend = vi.fn();
+    const onReject = vi.fn();
+    renderWithMantine(
+      <SamplingRequestPanel
+        {...baseProps}
+        request={simpleRequest}
+        draftResult={blankDraft}
+        onAutoRespond={onAutoRespond}
+        onSend={onSend}
+        onReject={onReject}
+      />,
+    );
+    await user.click(screen.getByRole("button", { name: "Auto-respond" }));
+    await user.click(screen.getByRole("button", { name: "Send Response" }));
+    await user.click(screen.getByRole("button", { name: "Reject" }));
+    expect(onAutoRespond).toHaveBeenCalledTimes(1);
+    expect(onSend).toHaveBeenCalledTimes(1);
+    expect(onReject).toHaveBeenCalledTimes(1);
+  });
+
+  it("displays the existing stopReason in the Select", () => {
+    renderWithMantine(
+      <SamplingRequestPanel
+        {...baseProps}
+        request={simpleRequest}
+        draftResult={{ ...blankDraft, stopReason: "endTurn" }}
+      />,
+    );
+    const inputs = screen.getAllByDisplayValue("endTurn");
+    expect(inputs.length).toBeGreaterThan(0);
+  });
+});