react({ compiler: true }) ignores tsconfig jsxImportSource

[undefined1e4]

Describe the bug

Enabling the native React Compiler with react({ compiler: true }) changes the JSX runtime selected from each file's nearest tsconfig.json. With no explicit plugin-level jsxImportSource, a file configured to use @emotion/react instead imports react/jsx-runtime.

Expected: enabling the compiler should preserve the documented per-file tsconfig inference.

Two identical TSX files produce these imports:

Plugin options	styled/component.tsx (jsxImportSource: "@emotion/react")	plain/component.tsx (default React)
{ compiler: false }	@emotion/react/jsx-runtime	react/jsx-runtime
{ compiler: true }	react/jsx-runtime — incorrect	react/jsx-runtime
{ compiler: true, jsxImportSource: "@emotion/react" }	@emotion/react/jsx-runtime	@emotion/react/jsx-runtime

The last row is expected global-override behavior, not another bug: setting one global source cannot preserve both per-file configurations.

Reproduction

Self-contained files below. No pragmas, Babel, CSS plugins, or workspace tooling are involved. Runtime imports are externalized so the test can inspect the emitted specifiers without installing or executing React/Emotion.

Create the files in an empty directory, then run:

npm install --ignore-scripts
npm run repro

The script checks the compiler-disabled baseline, prints all three configurations, and exits with code 1 for the compiler-enabled regression. The final global-override demonstration does not affect the exit code.

Complete reproduction files

package.json

{
  "name": "vite-jsx-import-source-repro",
  "private": true,
  "type": "module",
  "scripts": {
    "repro": "node repro.mjs"
  },
  "devDependencies": {
    "@vitejs/plugin-react": "6.1.1",
    "oxc-transform-react": "0.145.0",
    "vite": "8.2.2"
  }
}

styled/tsconfig.json

{
  "compilerOptions": {
    "jsx": "react-jsx",
    "jsxImportSource": "@emotion/react"
  }
}

plain/tsconfig.json

{
  "compilerOptions": {
    "jsx": "react-jsx"
  }
}

Both styled/component.tsx and plain/component.tsx:

export function Component() {
  return <div>Hello</div>;
}

repro.mjs

import assert from "node:assert/strict";
import { fileURLToPath } from "node:url";

import react from "@vitejs/plugin-react";
import { build } from "vite";

const root = fileURLToPath(new URL(".", import.meta.url));
const expected = {
  styled: "@emotion/react/jsx-runtime",
  plain: "react/jsx-runtime",
};

let failures = 0;
for (const options of [
  { compiler: false },
  { compiler: true },
  { compiler: true, jsxImportSource: "@emotion/react" },
]) {
  const buildOutput = await build({
    root,
    configFile: false,
    logLevel: "silent",
    plugins: [react(options)],
    build: {
      write: false,
      minify: false,
      lib: {
        entry: {
          styled: `${root}styled/component.tsx`,
          plain: `${root}plain/component.tsx`,
        },
        formats: ["es"],
      },
      rolldownOptions: {
        external: /^(react|@emotion\/react)(\/|$)/,
        output: { preserveModules: true },
      },
    },
  });

  console.log(JSON.stringify(options));
  const chunks = [buildOutput].flat().flatMap((output) => output.output);
  for (const [entry, runtime] of Object.entries(expected)) {
    const chunk = chunks.find(
      (output) =>
        output.type === "chunk" &&
        output.facadeModuleId === `${root}${entry}/component.tsx`,
    );
    assert.ok(chunk, `Missing entry: ${entry}`);
    const imports = chunk.imports.filter((specifier) =>
      specifier.endsWith("/jsx-runtime"),
    );
    const matches = imports.length === 1 && imports[0] === runtime;
    console.log(
      `  ${entry}: ${imports.join(", ")} (${matches ? "PASS" : "FAIL"})`,
    );
    if (!options.compiler) assert.deepEqual(imports, [runtime]);
    if (!matches && !options.jsxImportSource) failures++;
  }
}

process.exitCode = failures ? 1 : 0;

System Info

macOS 26.4.1 arm64
Node 22.14.0
npm 10.9.2
vite 8.2.2
@vitejs/plugin-react 6.1.1
oxc-transform-react 0.145.0

Also reproduced after a clean npm ci --ignore-scripts using the generated lockfile.

Related context

• fix(react): respect tsconfig jsxImportSource by default #726 restored tsconfig inference in the regular JSX transform path. It predates the native compiler integration from feat(react): add native React Compiler support #1419 and does not cover this compiler-enabled path.
• Enabling React Compiler breaks JSX pragma handling #1224 concerns file-level JSX pragma comments being moved below imports. This reproduction contains no pragmas, so moving comments cannot address this case.
• In the native compiler transform, jsx.importSource is supplied from reactOptions.jsxImportSource, and JSX is already lowered before Vite's regular transform can apply the file's tsconfig.

[doctor8296]

I have exactly the same problem!