refactor: remove gulp-typescript

example/gulpfile.ts

@@ -1,29 +1,37 @@
 const { src, dest, series, watch, task } = require("gulp");
-const ts = require("gulp-typescript");
+const ts = require("typescript");
 const rollup = require("rollup");
-const typescript = require("@rollup/plugin-typescript");
+const typescriptPlugin = require("@rollup/plugin-typescript");
 const { nodeResolve } = require("@rollup/plugin-node-resolve");
 
-const tsProjectLib = ts.createProject("../tsconfig.json", {
-  rootDir: "../",
-});
 const LIB_SOURCE = "../src/**/*.ts";
+const tsConfigPath = "../tsconfig.json";
 
 const transpileLibTypescript = () =>
-  src(LIB_SOURCE).pipe(tsProjectLib()).pipe(dest("../dist"));
+  src(LIB_SOURCE, { sourcemaps: true })  // initialize sourcemaps
+    .pipe(dest("../dist", { sourcemaps: '.' }));  // write sourcemaps to the same directory
+
+function compileTypeScript(content, file) {
+  const tsConfig = require(tsConfigPath);
+  const result = ts.transpileModule(content.toString(), {
+    compilerOptions: tsConfig.compilerOptions,
+    fileName: file.path,
+  });
+  return result.outputText;
+}
 
-const buildExample = (done: () => void) =>
+const buildExample = (done) =>
   rollup
     .rollup({
       input: "./helper.ts",
-      plugins: [nodeResolve(), typescript()],
+      plugins: [nodeResolve(), typescriptPlugin()],
     })
     .then((bundle) =>
       bundle.write({
         dir: "dist",
         format: "esm",
         sourcemap: true,
-      }),
+      })
     )
     .then(() => {
       done();
@@ -39,7 +47,7 @@ task("default", () => {
       "*.ts",
       "node_modules/@mikaello/emit-punch-cards-communication/dist/**/*.js",
     ],
-    buildExample,
+    buildExample
   );
 });