AgentHub/client/src/components/lanes/__tests__/LaneGitBar.test.tsx

/**
 * @file LaneGitBar.test.tsx
 * @description Pins the lane git action row: the ahead/behind readout, which
 * buttons a repo with no remote may press, that it offers no commit (the
 * Changes panel's staged-only box owns that), that a dirty tree blocks the branch switch client-side (the server
 * refuses it too), and that a failed action shows git's own words rather than
 * a generic sentence.
 * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
 */

import { describe, it, expect, vi, beforeEach } from "vitest";
import { render, screen, waitFor } from "@testing-library/react";
import userEvent from "@testing-library/user-event";
import { LaneGitBar } from "../LaneGitBar";
import { api } from "../../../lib/api";
import type { LaneGitFacts } from "../../../lib/types";

vi.mock("../../../lib/api", () => ({
  api: { lanes: { gitAction: vi.fn(), gitBranches: vi.fn() } },
}));

function facts(over: Partial<Extract<LaneGitFacts, { available: true }>> = {}): LaneGitFacts {
  return {
    available: true,
    branch: "feat/thing",
    head: "9b3e74a",
    subject: "wip",
    dirty: 2,
    untracked: 1,
    files: [],
    hasRemote: true,
    upstream: "origin/feat/thing",
    ahead: 2,
    behind: 1,
    ...over,
  };
}

beforeEach(() => {
  vi.mocked(api.lanes.gitAction).mockReset().mockResolvedValue({
    action: "fetch",
    ok: true,
    output: "",
  });
  vi.mocked(api.lanes.gitBranches)
    .mockReset()
    .mockResolvedValue({
      available: true,
      branches: ["development", "feat/thing"],
      current: "feat/thing",
      worktrees: [],
    });
});

describe("LaneGitBar", () => {
  it("shows both sides of the upstream comparison", () => {
    render(<LaneGitBar laneId={3} git={facts()} onChanged={vi.fn()} />);
    const tracking = screen.getByTestId("lane-git-tracking");
    expect(tracking).toHaveTextContent("2");
    expect(tracking).toHaveTextContent("1");
  });

  it("disables the network actions when the repo has no remote", () => {
    render(
      <LaneGitBar
        laneId={3}
        git={facts({ hasRemote: false, upstream: null })}
        onChanged={vi.fn()}
      />
    );
    expect(screen.getByRole("button", { name: /Fetch/ })).toBeDisabled();
    expect(screen.getByRole("button", { name: /Push/ })).toBeDisabled();
    // Local actions stay available — a repo with no remote still branches.
    expect(screen.getByRole("button", { name: /Branch/ })).toBeEnabled();
  });

  it("offers no commit at all — that is the Changes panel's staged-only box", () => {
    render(<LaneGitBar laneId={3} git={facts()} onChanged={vi.fn()} />);
    expect(screen.queryByRole("button", { name: /Commit/ })).toBeNull();
  });

  it("loads the branch list on demand and refuses to switch while dirty", async () => {
    const user = userEvent.setup();
    render(<LaneGitBar laneId={3} git={facts()} onChanged={vi.fn()} />);

    await user.click(screen.getByRole("button", { name: /Branch/ }));
    await waitFor(() => expect(api.lanes.gitBranches).toHaveBeenCalledWith(3));
    await user.selectOptions(await screen.findByLabelText("Switch branch…"), "development");
    // Picking is harmless; applying is what a dirty tree blocks.
    expect(screen.getByRole("button", { name: "Switch branch" })).toBeDisabled();
    expect(api.lanes.gitAction).not.toHaveBeenCalled();
  });

  it("switches branch on a clean tree", async () => {
    const user = userEvent.setup();
    render(<LaneGitBar laneId={3} git={facts({ dirty: 0, untracked: 0 })} onChanged={vi.fn()} />);

    await user.click(screen.getByRole("button", { name: /Branch/ }));
    const select = await screen.findByLabelText("Switch branch…");
    await user.selectOptions(select, "development");
    await user.click(screen.getByRole("button", { name: "Switch branch" }));

    await waitFor(() =>
      expect(api.lanes.gitAction).toHaveBeenCalledWith(3, "switch", { branch: "development" })
    );
  });

  it("re-reads the branch list after a switch, so the branch just left is not held", async () => {
    const user = userEvent.setup();
    render(<LaneGitBar laneId={3} git={facts({ dirty: 0, untracked: 0 })} onChanged={vi.fn()} />);
    await user.click(screen.getByRole("button", { name: /Branch/ }));
    await user.selectOptions(await screen.findByLabelText("Switch branch…"), "development");
    await user.click(screen.getByRole("button", { name: "Switch branch" }));
    await waitFor(() => expect(api.lanes.gitBranches).toHaveBeenCalledTimes(2));
  });

  it("creates a branch without switching, then offers a sibling lane on it", async () => {
    const user = userEvent.setup();
    const onNewLane = vi.fn();
    render(
      <LaneGitBar
        laneId={3}
        git={facts({ dirty: 0, untracked: 0 })}
        onChanged={vi.fn()}
        onNewLane={onNewLane}
      />
    );

    await user.click(screen.getByRole("button", { name: /Branch/ }));
    await user.type(await screen.findByLabelText("New branch name…"), "feat/sibling");
    await user.click(screen.getByRole("button", { name: "Create" }));
    await waitFor(() =>
      expect(api.lanes.gitAction).toHaveBeenCalledWith(3, "branch-create", {
        branch: "feat/sibling",
      })
    );

    await user.selectOptions(screen.getByLabelText("Switch branch…"), "development");
    await user.click(screen.getByRole("button", { name: "New lane here" }));
    expect(onNewLane).toHaveBeenCalledWith("development");
  });

  it("offers a sibling lane only on a branch no worktree holds — the server refuses the rest", async () => {
    vi.mocked(api.lanes.gitBranches).mockResolvedValue({
      available: true,
      branches: ["development", "feat/thing", "feat/free"],
      current: "feat/thing",
      worktrees: [
        { path: "/repo/lane3", branch: "feat/thing" },
        { path: "/repo/dev", branch: "development" },
      ],
    });
    const user = userEvent.setup();
    render(<LaneGitBar laneId={3} git={facts()} onChanged={vi.fn()} onNewLane={vi.fn()} />);
    await user.click(screen.getByRole("button", { name: /Branch/ }));
    const select = await screen.findByLabelText("Switch branch…");
    const newLane = () => screen.getByRole("button", { name: "New lane here" });

    // This lane's own branch: its worktree is this lane.
    await user.selectOptions(select, "feat/thing");
    expect(newLane()).toBeDisabled();
    // Held by another worktree: git allows one worktree per branch (EBRANCHBUSY).
    await user.selectOptions(select, "development");
    expect(newLane()).toBeDisabled();
    expect(newLane()).toHaveAttribute("title", expect.stringContaining("/repo/dev"));

    await user.selectOptions(select, "feat/free");
    expect(newLane()).toBeEnabled();
  });

  it("prints git's own rejection text when an action fails", async () => {
    const user = userEvent.setup();
    vi.mocked(api.lanes.gitAction).mockRejectedValue(
      new Error("git push failed\n! [rejected] main -> main (non-fast-forward)")
    );
    render(<LaneGitBar laneId={3} git={facts()} onChanged={vi.fn()} />);

    await user.click(screen.getByRole("button", { name: /Push/ }));
    expect(await screen.findByTestId("lane-git-bar-error")).toHaveTextContent("non-fast-forward");
  });

  it("re-reads the branch list for the new lane instead of showing the old one's", async () => {
    const user = userEvent.setup();
    const { rerender } = render(<LaneGitBar laneId={3} git={facts()} onChanged={vi.fn()} />);
    await user.click(screen.getByRole("button", { name: /Branch/ }));
    await user.selectOptions(await screen.findByLabelText("Switch branch…"), "development");

    rerender(<LaneGitBar laneId={4} git={facts()} onChanged={vi.fn()} />);
    expect(screen.queryByLabelText("Switch branch…")).toBeNull();
    await user.click(screen.getByRole("button", { name: /Branch/ }));
    await waitFor(() => expect(api.lanes.gitBranches).toHaveBeenCalledWith(4));
    expect(await screen.findByLabelText("Switch branch…")).toHaveValue("");
  });

  it("sends one branch-create for a double Enter", async () => {
    vi.mocked(api.lanes.gitAction).mockReturnValue(new Promise(() => {}));
    const user = userEvent.setup();
    render(<LaneGitBar laneId={3} git={facts()} onChanged={vi.fn()} />);
    await user.click(screen.getByRole("button", { name: /Branch/ }));
    await user.type(await screen.findByLabelText(/New branch/), "feat/once{Enter}{Enter}");
    expect(api.lanes.gitAction).toHaveBeenCalledTimes(1);
  });

  it("forgets which branches the previous lane's worktrees held once the lane changes", async () => {
    let resolveOld: (v: Awaited<ReturnType<typeof api.lanes.gitBranches>>) => void = () => {};
    vi.mocked(api.lanes.gitBranches).mockReturnValueOnce(
      new Promise((r) => {
        resolveOld = r;
      })
    );
    const user = userEvent.setup();
    const { rerender } = render(
      <LaneGitBar laneId={3} git={facts()} onChanged={vi.fn()} onNewLane={vi.fn()} />
    );
    await user.click(screen.getByRole("button", { name: /Branch/ }));

    rerender(<LaneGitBar laneId={4} git={facts()} onChanged={vi.fn()} onNewLane={vi.fn()} />);
    await user.click(screen.getByRole("button", { name: /Branch/ }));
    const select = await screen.findByLabelText("Switch branch…");
    await waitFor(() => expect(api.lanes.gitBranches).toHaveBeenCalledWith(4));
    // Lane 3's answer lands late: its worktree held `development`.
    resolveOld({
      available: true,
      branches: ["development", "feat/thing"],
      current: "feat/thing",
      worktrees: [{ path: "/repo/dev", branch: "development" }],
    });
    await user.selectOptions(select, "development");
    const newLane = screen.getByRole("button", { name: "New lane here" });
    expect(newLane).toBeEnabled();
    expect(newLane).not.toHaveAttribute("title", expect.stringContaining("/repo/dev"));
  });

  it("claims no sync state when the upstream comparison could not be counted", () => {
    render(
      <LaneGitBar
        laneId={3}
        git={facts({ upstream: "origin/gone", ahead: null, behind: null })}
        onChanged={vi.fn()}
      />
    );
    expect(screen.queryByText("in sync")).toBeNull();
    expect(screen.queryByTestId("lane-git-tracking")).toBeNull();
  });

  it("explains a push with nowhere to go instead of the server's generic text", async () => {
    const user = userEvent.setup();
    vi.mocked(api.lanes.gitAction).mockRejectedValue(
      Object.assign(new Error("this repository has no remote to push to"), { code: "ENOREMOTE" })
    );
    render(<LaneGitBar laneId={3} git={facts()} onChanged={vi.fn()} />);
    await user.click(screen.getByRole("button", { name: /Push/ }));
    expect(await screen.findByTestId("lane-git-bar-error")).toHaveTextContent(
      "No remote to push to or pull from"
    );
  });
});