Magento2: Less SourceMaps Path is not corret

[gizmocn]

Summary (*)

Grunt generate wrong less sourceMaps path, both Chrome and Firefox can not find sourceMaps files

Environment

OS: Ubuntu 18.04 with apache and php 7.1.x
Magento Version: 2.3.0

How to Reproduce

1. Download Magento 2.3.0 Open Source with Sample from Official Site.
2. Install it on local server.
3. Install and configure grunt according to https://devdocs.magento.com/guides/v2.3/frontend-dev-guide/css-topics/css_debug.html
4. Run: grunt clean, grunt exec, grunt less:luma.
5. Browser can not find less sourceMaps files.

It is very difficult to reproduce on on vanilla Magento instance, as the issue need a lot of CLI operations to install node.js, npm etc.

Examples (*)

Use Grunt to compile Less file, and Grunt add sourceMaps path is:
/*# sourceMappingURL=pub/static/frontend/Magento/luma/en_US/css/styles-l.css.map */
In order to let browser to find the sourceMpas file, it should be
/*# sourceMappingURL=styles-l.css.map */

Proposed solution

Try to change less.js but failed.

[magento-engcom-team]

Hi @gizmocn. Thank you for your report.
To help us process this issue please make sure that you provided the following information:

• [ ] Summary of the issue
• [ ] Information on your environment
• [ ] Steps to reproduce
• [ ] Expected and actual results

Please make sure that the issue is reproducible on the vanilla Magento instance following Steps to reproduce. To deploy vanilla Magento instance on our environment, please, add a comment to the issue:

@magento-engcom-team give me 2.3-develop instance - upcoming 2.3.x release

For more details, please, review the Magento Contributor Assistant documentation.

@gizmocn do you confirm that you was able to reproduce the issue on vanilla Magento instance following steps to reproduce?

• [ ] yes
• [ ] no

[gizmocn]

@magento-engcom-team give me 2.3-develop instance - upcoming 2.3.x release

[magento-engcom-team]

Hi @gizmocn. Thank you for your request. I'm working on Magento 2.3-develop instance for you

[magento-engcom-team]

Hi @gizmocn, here is your Magento instance.
Admin access: https://i-20952-2-3-develop.instances.magento-community.engineering/admin
Login: admin Password: 123123q
Instance will be terminated in up to 3 hours.

[gizmocn]

I have tried vanilla Magento instance, but I have no idea about how to run CLI command on it, the issue need to install node.js npm and grunt etc.

[amol2jcommerce]

@magento-engcom-team give me 2.3-develop instance

[magento-engcom-team]

Hi @amol2jcommerce. Thank you for your request. I'm working on Magento 2.3-develop instance for you

[magento-engcom-team]

Hi @amol2jcommerce, here is your Magento instance.
Admin access: https://i-20952-2-3-develop.instances.magento-community.engineering/admin
Login: admin Password: 123123q
Instance will be terminated in up to 3 hours.

[magento-engcom-team]

Hi @engcom-backlog-nazar. Thank you for working on this issue.
In order to make sure that issue has enough information and ready for development, please read and check the following instruction: :point_down:

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  Details

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• [x] 2. Verify that issue has a meaningful description and provides enough information to reproduce the issue. If the report is valid, add Issue: Clear Description label to the issue by yourself.

• [x] 3. Add Component: XXXXX label(s) to the ticket, indicating the components it may be related to.

• [x] 4. Verify that the issue is reproducible on 2.3-develop branch

  Details

  - Add the comment @magento-engcom-team give me 2.3-develop instance to deploy test instance on Magento infrastructure.
  - If the issue is reproducible on 2.3-develop branch, please, add the label Reproduced on 2.3.x.
  - If the issue is not reproducible, add your comment that issue is not reproducible and close the issue and _stop verification process here_!
  

• [ ] 5. Verify that the issue is reproducible on 2.2-develop branch.

  Details

  - Add the comment @magento-engcom-team give me 2.2-develop instance to deploy test instance on Magento infrastructure.
  - If the issue is reproducible on 2.2-develop branch, please add the label Reproduced on 2.2.x

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[magento-engcom-team]

:white_check_mark: Confirmed by @engcom-backlog-nazar
Thank you for verifying the issue. Based on the provided information internal tickets MAGETWO-98051 were created

Issue Available: @engcom-backlog-nazar, _You will be automatically unassigned. Contributors/Maintainers can claim this issue to continue. To reclaim and continue work, reassign the ticket to yourself._

[omiroshnichenko]

Hi @gizmocn, I'm not able to reproduce your issue. Please, take a look at my steps and add additional steps/information to reproduce this issue.

1. Installed Magento 2.3-develop
2. Node.js v8.11.3
3. grunt clean
   
4. grunt exec (screenshot with success message)
   
5. grunt less:luma
   
6. Magento storefront Home page
   
   
7. Sources tab
   

[ghost]

@omiroshnichenko node -v v11.9.0

[ghost]

Hi all sorry i'm have wrong configuration, now all works as expected.

[grudado]

Hi all sorry i'm have wrong configuration, now all works as expected.

@engcom-backlog-nazar What did you? I have the same issue.
Thanks in advance

[sunilit42]

@tratta i am facing same issue, in browser not showing source map, can you please help us on that.

[grudado]

@sunilit42 I made some changes on theme

x3: {
        area: 'frontend',
        name: 'Grudado/x3',
        locale: 'pt_BR',
        options: {
            sourceMap: true,
            strictImports: false,
            sourceMapRootpath: '/',
            dumpLineNumbers: false, // use 'comments' instead false to output line comments for source
            ieCompat: false
        },
        files: [
            'css/styles-m',
            'css/styles-l',
            'css/email',
            'css/email-inline'
        ],
        dsl: 'less'
    },

and less.js

var lessOptions = {
    options: {
        sourceMap: true,
        strictImports: false,
        sourceMapRootpath: '/',
        sourceMapFileInline: 'true',
        dumpLineNumbers: false, // use 'comments' instead false to output line comments for source
        ieCompat: false
    },
    setup: {
        files: {
            '<%= path.css.setup %>/setup.css': '<%= path.less.setup %>/_setup.less'
        }
    },
    updater: {
        files: {
            '<%= path.css.updater %>/updater.css': '<%= path.less.setup %>/_setup.less'
        }
    },
    documentation: {
        files: {
            '<%= path.doc %>/docs.css': '<%= path.doc %>/source/docs.less'
        }
    }
};

[flahub]

It worked for me rename package.json.example to package.json, that is what I was missing. :-)

[Eddcapone]

Make sure that the name you set in the grunt config "matches" the path which you have set in the registration.php of your theme. For example I set the name in the grunt config to Company/Base but in my registration.php it was set to 'frontend/company/base'. So I had to change the name in the grunt config to company/base. More details.