import { fileURLToPath } from "node:url";import { defineConfig } from "vitest/config";import babel from "@rolldown/plugin-babel";import { reactCompilerPreset } from "@vitejs/plugin-react";import { lingui, linguiTransformerBabelPreset } from "@lingui/vite-plugin";import { fsModuleCacheKey } from "./scripts/vitest-fs-cache-key.ts";import { BalancedShardSequencer } from "./scripts/vitest-balanced-shards.ts";import { privateFontsPlugin } from "./scripts/private-fonts.ts";import { reactCompilerSuppressionRules } from "./scripts/react-compiler-suppressions.ts"; export default defineConfig({  // The suite runs the compiled output, the same as the app: vite.config.ts  // applies this preset pair in this order, and for a long time this file did  // not, so nothing ever exercised the code that actually ships.  // `react-compiler-guard.test.ts` counts *bailouts*, which means it watches the  // files the compiler skips and says nothing about the ones it compiles — a  // component with zero bailouts was the least-tested code in the repo.  //  // It costs about 18% wall clock (transform 15s → 59s, run 64s → 76s). That is  // the price of testing what ships; do not trade it back.  //  // Turning it on exposed two live defects, both of the same shape — state React  // cannot observe changing, read during render, then memoized away:  // `AppToast`'s actions came from a module map keyed on an entry id that does  // not move when the actions are replaced (app-log-store.ts now pairs them into  // one subscribed snapshot), and `Mirror` subscribed to a revision counter it  // discarded instead of to the source text it renders (Mirror-host.tsx). Both  // were intermittent in real use, papered over by incidental re-renders from  // neighbouring components.  //  // Babel applies presets right-to-left: Lingui macros must expand first so the  // compiler sees ordinary React rather than macro-generated components.  plugins: [    lingui(),    babel({      presets: [        reactCompilerPreset({ target: "19", eslintSuppressionRules: reactCompilerSuppressionRules }),        linguiTransformerBabelPreset(),      ],    }),    fsModuleCacheKey(fileURLToPath(new URL(".", import.meta.url))),    // Tests run as a build without the private fonts, whatever this machine    // has; a suite that needs their license mocks the module.    privateFontsPlugin({ directory: null }),  ],  resolve: {    // Keep the `@/…` alias in sync with vite.config.ts / tsconfig so tests can    // import shadcn/ui components the same way the app does.    alias: {      "@": fileURLToPath(new URL("./src", import.meta.url)),    },  },  test: {    // Persist transformed modules in node_modules/.experimental-vitest-cache    // between runs. The React Compiler and Lingui transforms above dominate a    // focused run's startup (app-welcome: 21–35 s uncached, 7–9 s warm); the cache is    // cold in a fresh worktree, and fsModuleCacheKey (above) keys every entry on    // the installed dependencies and Lingui config and keeps catalogs out of it.    // `pnpm vitest --clearCache` drops it by hand.    experimental: { fsModuleCache: true },    // literature-worker has its own vitest config using the Cloudflare Workers    // pool; its tests cannot run under this runner (`cloudflare:` imports).    //    // `.tmp/` is the scratch directory for throwaway builds and debug dumps. A    // checkout staged in there brings its own test suite, and vitest's default    // glob happily collected hundreds of foreign tests that fail under this    // config — enough to make `pnpm check` unusable. A Synara checkout staged    // in the worktree as `.synara-src/` (SYNARA_SOURCE_DIR) does the same.    exclude: ["**/node_modules/**", "literature-worker/**", ".tmp/**", ".synara-src/**"],    environment: "jsdom",    setupFiles: ["./src/platform/test-setup.ts"],    // Several suites mount the complete app or visual Markdown editor. Running    // those memory-heavy files beside each other on a high-core machine starves    // their async UI assertions and makes unrelated tests fail nondeterministically.    maxWorkers: 1,    // Room for the slowest test to finish on a loaded machine rather than a    // quiet one; the per-assertion wait is set alongside it in test-setup.ts.    testTimeout: 20_000,    // `--shard` (CI's three test jobs) splits by estimated cost rather than    // file count, so the App suites do not pile onto one shard.    sequence: { sequencer: BalancedShardSequencer },  },});