esbuild-hook.js

/* istanbul ignore file */

const Module = require("module");
const { transformSync } = require("esbuild");
const sourceMapSupport = require("source-map-support");

const cache = {};

function esbuildHook(code, filepath) {
  const result = transformSync(code, {
    target: "node16",
    sourcemap: "both",
    loader: "ts",
    format: "cjs",
    sourcefile: filepath,
  });

  cache[filepath] = {
    url: filepath,
    code: result.code,
    map: result.map,
  };

  return result.code;
}

sourceMapSupport.install({
  environment: "node",
  retrieveFile(pathOrUrl) {
    const file = cache[pathOrUrl];
    if (file) {
      return file.code;
    } else {
      return "";
    }
  },
});

const defaultLoader = Module._extensions[".js"];

Module._extensions[".ts"] = function (mod, filename) {
  if (filename.includes("node_modules")) {
    return defaultLoader(mod, filename);
  }

  const defaultCompile = mod._compile;
  mod._compile = function (code) {
    mod._compile = defaultCompile;
    return mod._compile(esbuildHook(code, filename), filename);
  };

  defaultLoader(mod, filename);
};