scripts[patch]: Fix reading original entrypoint file (#6591)

* scripts[patch]: Fix reading original entrypoint file

* chore: lint files

libs/langchain-scripts/src/build_v2.ts

@@ -490,17 +490,13 @@ function listEntrypoints(packageJson: Record<string, any>) {
 const checkAllowSideEffects = async (entrypoint: string): Promise<boolean> => {
   let entrypointContent: Buffer | undefined;
   try {
-    entrypointContent = await fs.promises.readFile(
-      `./dist/${entrypoint.replace(/^\.\//, "")}`
-    );
+    entrypointContent = await fs.promises.readFile(`./dist/${entrypoint}.js`);
     // eslint-disable-next-line @typescript-eslint/no-explicit-any
   } catch (e: any) {
     if (e.message.includes("ENOENT")) {
       // Entrypoint is likely via an `index.js` file, retry with `index.js` appended to path
       entrypointContent = await fs.promises.readFile(
-        `./dist/${entrypoint
-          .replace(/^\.\//, "")
-          .replace(/\.js$/, "")}/index.js`
+        `./dist/${entrypoint}/index.js`
       );
     }
   }
@@ -542,7 +538,12 @@ async function checkTreeShaking(config: LangChainConfig) {
 
     let hasUnexpectedSideEffects = sideEffects.length > 0;
     if (hasUnexpectedSideEffects) {
-      hasUnexpectedSideEffects = !(await checkAllowSideEffects(entrypoint));
+      // Map the entrypoint back to the actual file entrypoint using the LangChainConfig file
+      const actualEntrypoint =
+        config.entrypoints[entrypoint.replace(/^\.\/|\.js$/g, "")];
+      hasUnexpectedSideEffects = !(await checkAllowSideEffects(
+        actualEntrypoint
+      ));
     }
     reportMap.set(entrypoint, {
       log: sideEffects,