Duplicate selectors when use each loop syntax

[alireza-mh]

• Operating System: MacOS 10.14.5
• Node Version: 11.4.0
• NPM Version: 6.9.0
• webpack Version: 4.20.2
• less-loader Version: 5.0.0

Expected Behavior

when we create selectors with each keywords, for example, in the main file if we import main file with reference keyword our output should not have duplicate selectors.

Actual Behavior

these kinds of selectors will be duplicated on the output file

Code

each(range(1, 5), {
 .flex-@{value} {
   flex: @value
 }
})

How Do We Reproduce?

copy and paste flex generator code in one file and import it with reference in other less files.

there is a workaround for those who faced the same issue, you can put all generated selectors in one file and import it once in your js file.

[ohcrfpv]

same here

[alexander-akait]

We don't modify you input, because less works like that

[alireza-mh]

strange, it seems it is expected behavior according to this less issue:
less/less.js#3402

[alexander-akait]

Yes, we can't do something on our side, maybe cssnano allow to you remove unnecessary selectors