import { defineConfig } from "vitest/config";
import path from "node:path";

export default defineConfig({
  resolve: {
    alias: {
      "@": path.resolve(__dirname, "./src"),
    },
  },
  test: {
    environment: "node",
    // Scope explicitly to this repo's own tests/ dir — without this, Vitest's
    // default glob also picks up any stray sibling git worktree checked out
    // under .claude/worktrees/ (e.g. worktree-ui-basic), which isn't excluded
    // by Vitest's defaults since those only skip node_modules/.git/etc, not
    // .claude/. A stray worktree's stale test file still resolves the "@"
    // alias to *this* repo's src/ (see resolve.alias above, which is
    // __dirname-relative), so it silently runs old tests against current
    // code under a shared identity — confirmed happening in practice once a
    // second worktree existed.
    include: ["tests/**/*.test.ts"],
    setupFiles: ["./tests/setup.ts"],
    // Each test file gets its own throwaway Postgres database and its own
    // dedicated PrismaClient, wired up via a `vi.mock("@/lib/prisma", ...)`
    // factory in tests/setup.ts (not by mutating the ambient
    // process.env.DATABASE_URL, which used to be shared/racy across files —
    // see the long comment at the top of tests/setup.ts for the history).
    // With no mutable state shared between files, parallel file execution
    // (Vitest's default) is safe again.
  },
});