ECMASCRIPT6 error while building image on adobe as cloud service pipeline

[piyushmalikk120]

Hi,

We are facing an issue where build pipeline is failing while building image on adobe as cloud and started getting ECMASCRIPT6 related error(This language feature is only supported for ECMASCRIPT6 mode or better). The logs are related to both /apps and /libs files. Our build was working fine till we updated our aem version(to 2022.3.6698.20220318T233218Z) and started the pipeline. And then onwards pipeline started failing and started getting below logs

com.google.javascript.jscomp.LoggerErrorManager println
SEVERE: libs/fd/fdm/gui/components/admin/clientlibs/core.min.js:1288: ERROR - This language feature is only supported for ECMASCRIPT6 mode or better: let declaration.
let panelStackId = contentPanelStack.hasAttribute("id") ? contentPanelStack.getAttribute("id") : Coral.commons.getUID();
^

2022 4:19:19 AM com.google.javascript.jscomp.LoggerErrorManager printSummary
WARNING: 0 error(s), 2 warning(s)
Mar 31, 2022 4:19:20 AM com.google.javascript.jscomp.LoggerErrorManager println
SEVERE: apps/<brand-name>-clientlibs/styles/components/verint_sdk_application.min.js:2394: ERROR - This language feature is only supported for ECMASCRIPT6 mode or better: block-scoped function declaration.
function h(a, b, c) {

4:19:20 AM com.google.javascript.jscomp.LoggerErrorManager printSummary
WARNING: 1 error(s), 0 warning(s)
Mar 31, 2022 4:19:21 AM com.google.javascript.jscomp.LoggerErrorManager println
SEVERE: apps/<brand-name>-aem-commons/components/composite/pagetabs/pagedropdown/clientlibs.min.js:7: ERROR - This language feature is only supported for ECMASCRIPT6 mode or better: arrow function.
Coral.commons.ready($dialogEl, () =>

Can someone please guide me.

[DEBAL_DAS · Accepted solution]

Let me share my experience from AEM 6.5 context.

Earlier I saw such type of error messages[not exactly the same] during minification in error.log file as Front End team kept saying JS minification wasn't working.

I did troubleshoot the issue and defined below steps   -

1. AEM 6.5 uses following closure-compiler-v20190121.jar for js minification, also highlighted in below screenshot -

2. If I take a closure look , I could see com.google.javascript is part of this closure compiler bundle.

3. Next I downloaded the bundle from aeminstance\crx-quickstart\launchpad\felix\bundle290. Bundle ID may vary in your case.

4. To understand the minification issue , I have executed below command to compile the Javascript file -

     java -jar compiler.jar --js hello.js --js_output_file hello-compiled.js

[https://developers.google.com/closure/compiler/docs/gettingstarted_app]

It threw error during compilation. Then I requested Front End team to fix those issue so that minification works.

This steps will work with project specific client libraries[js files].

Even I faced issue with ECMASCRIPT versions also . I spoke to UI architect and he told me use latest ECMASCRIPT edition. [Please talk to your UI team lead or UI architect in details]