vite-plugin-relay.ts

import babelPluginRelay from "babel-plugin-relay";
import { Plugin } from "vite";
import { transformSync } from "@babel/core";

export function relay(): Plugin {
  return {
    name: "vite:relay",
    transform(src, filePath) {
      if (
        !filePath.includes("node_modules") &&
        /\.tsx?$/.test(filePath) &&
        src.includes("graphql`")
      ) {
        const out = transformSync(src, {
          plugins: [[babelPluginRelay]],
          code: true,
          sourceMaps: true,
        });
        if (!out?.code) {
          throw new Error(`vite:relay plugin failed to transform ${filePath}`);
        }
        return {
          code: out.code,
          map: out.map,
        };
      }
      return void 0;
    },
  };
}