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

/**
 * @file Tests for the merge-conflict view: both sides of each block shown
 * under their own labels, one choice per block with undo, Save only once
 * every block is chosen — and Save writes the chosen text over the version
 * opened, then marks the file resolved. Whole-file ours/theirs reuse
 * `resolve`.
 * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
 */

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

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

const LINES = [
  "top",
  "<<<<<<< HEAD",
  "mine",
  "=======",
  "theirs",
  ">>>>>>> origin/main",
  "middle",
  "<<<<<<< HEAD",
  "a",
  "=======",
  "b",
  ">>>>>>> origin/main",
];

beforeEach(() => {
  vi.mocked(api.lanes.gitFile)
    .mockReset()
    .mockResolvedValue({
      available: true,
      path: "a.txt",
      rev: "work",
      lines: LINES,
      truncated: false,
      binary: false,
      sha: "s1",
    } as never);
  vi.mocked(api.lanes.gitSaveFile)
    .mockReset()
    .mockResolvedValue({ available: true } as never);
  vi.mocked(api.lanes.gitAction)
    .mockReset()
    .mockResolvedValue({ action: "resolve", ok: true, output: "" });
});

const blocks = () => screen.getAllByTestId("conflict-block");

describe("LaneConflictView", () => {
  it("shows both sides under their labels and saves once every block is chosen", async () => {
    const user = userEvent.setup();
    const onResolved = vi.fn();
    render(<LaneConflictView laneId={3} path="a.txt" onResolved={onResolved} onEdit={vi.fn()} />);

    const [first, second] = (await screen.findAllByTestId("conflict-block")) as [
      HTMLElement,
      HTMLElement,
    ];
    expect(first).toHaveTextContent("Mine (HEAD)");
    expect(first).toHaveTextContent("Theirs (origin/main)");
    const save = screen.getByRole("button", { name: "Save and mark resolved" });
    expect(save).toBeDisabled();

    await user.click(within(first).getByRole("button", { name: "Keep mine" }));
    // Chosen: the block is plain text now, with an undo.
    await user.click(within(blocks()[0]!).getByRole("button", { name: "Undo" }));
    await user.click(within(blocks()[0]!).getByRole("button", { name: "Take theirs" }));
    await user.click(within(second).getByRole("button", { name: "Keep both" }));
    expect(save).toBeEnabled();
    await user.click(save);

    await waitFor(() =>
      expect(api.lanes.gitSaveFile).toHaveBeenCalledWith(
        3,
        "a.txt",
        "top\ntheirs\nmiddle\na\nb",
        "s1"
      )
    );
    await waitFor(() =>
      expect(api.lanes.gitAction).toHaveBeenCalledWith(3, "resolve", {
        path: "a.txt",
        side: "done",
      })
    );
    expect(onResolved).toHaveBeenCalled();
  });

  it("takes a whole side for the file through resolve", async () => {
    const user = userEvent.setup();
    const onResolved = vi.fn();
    render(<LaneConflictView laneId={3} path="a.txt" onResolved={onResolved} onEdit={vi.fn()} />);
    await screen.findAllByTestId("conflict-block");
    await user.click(screen.getByRole("button", { name: "Take all theirs" }));
    await waitFor(() =>
      expect(api.lanes.gitAction).toHaveBeenCalledWith(3, "resolve", {
        path: "a.txt",
        side: "theirs",
      })
    );
    expect(onResolved).toHaveBeenCalled();
    expect(api.lanes.gitSaveFile).not.toHaveBeenCalled();
  });

  it("offers the plain editor when the markers do not balance", async () => {
    vi.mocked(api.lanes.gitFile).mockResolvedValue({
      available: true,
      path: "a.txt",
      rev: "work",
      lines: ["<<<<<<< HEAD", "x"],
      truncated: false,
      binary: false,
      sha: "s1",
    } as never);
    const user = userEvent.setup();
    const onEdit = vi.fn();
    render(<LaneConflictView laneId={3} path="a.txt" onResolved={vi.fn()} onEdit={onEdit} />);
    await screen.findByText(/markers do not line up/);
    await user.click(screen.getByRole("button", { name: "Edit by hand" }));
    expect(onEdit).toHaveBeenCalled();
  });
});