feat: improve warning of conflict order

[laysent]

This PR contains a:

• bugfix
• new feature
• code refactor
• test update
• typo fix
• metadata update

Motivation / Use-Case

Many issues have been raised related to the warning of mini-css-extract-plugin regarding the conflict of order (example: #382 and #250). For me, the warning is a bit confusing as it does not provide enough details of why it goes wrong.

In this PR, I am trying to provide more info about:

• what module has been added to the css asset;
• why adding this module creates warnings;
• which chunks you should probably take a look into.

In current version, running the unit test will generate the following warning:

WARNING in chunk styles [mini-css-extract-plugin]
Conflicting order between:
* css xxx/css-loader/dist/cjs.js!./e1.css
* css xxx/css-loader/dist/cjs.js!./e2.css

In this PR version, running the unit test will generate the following warning:

WARNING in chunk styles [mini-css-extract-plugin]
Following module has been added:
 * css xxx/css-loader/dist/cjs.js!./e1.css
while this module as dependencies that haven't been added before:
 * css xxx/css-loader/dist/cjs.js!./e2.css (used previous to added module in chunk entry2)

Hopefully people seeing this warning will get an idea of checking the files in entry2, then put e2.css import later than e1.css import.

Breaking Changes

No breaking changes.

Additional Info

[jsf-clabot]

All committers have signed the CLA.

[codecov]

Codecov Report

Merging #465 into master will increase coverage by 0.42%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #465      +/-   ##
==========================================
+ Coverage   88.17%   88.59%   +0.42%     
==========================================
  Files           5        5              
  Lines         406      421      +15     
  Branches       86       90       +4     
==========================================
+ Hits          358      373      +15     
  Misses         46       46              
  Partials        2        2

Impacted Files	Coverage Δ
src/index.js	88.15% <100%> (+0.9%)	⬆️

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[alexander-akait]

Please accept CLA and add test case, thanks

[laysent]

Please accept CLA and add test case, thanks

@evilebottnawi Hi, I have added simple unit test for it and signed CLA. Also modified the phrase a little bit. Let me know if you have any suggestion.

[alexander-akait]

Please fix test for windows

[laysent]

Windows test has been fixed, while lint still fails. Seems to be an issue with prettier.

[alexander-akait]

@laysent let's update lock file too (just remove old lock file and run again npm i)

[laysent]

@evilebottnawi updated! :-)

[alexander-akait]

Good job, thanks!