remove NamedModulesPlugin from production build

[just-boris]

Follow-up for the discussion in #1450 (comment)

All examples are still build, plus there is my two simple demo pages:

• https://public-iubaybnfnq.now.sh/ - current master. This file has absolute paths inside.
• https://public-itvcluqrtd.now.sh/ - Version from this PR. This file doesn't have paths.

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[jquense]

I'm catching up with convo in #1450 but my main concern here is that it is going to bust long term caching even more than it is already. I believe with need to replace this with something that provides stable id/names otherwise the overall content hash is gonna constantly change (unless i'm miss understanding the failings of webpack's LTH)

[just-boris]

@jquense your concern is ok, but look at the filenames from my links of the example above. They both end with 4de036b7fc4e26c86a08. Module name is not taken into hash calculation at all.

This is actually the issue, that I am trying to fix. Module name has become different, but filename was not changed. Browser returns cached chunk -> main app.js expects different modules inside -> everything blows up.

Currently at least I will get consistent build output, that doesn't depend from project files location in the file system.

[just-boris]

@KyleAMathews the AppVeyor run has failed before the actual build has even started. Do you have a button to restart the build?

[KyleAMathews]

@jquense the fix is we added HashedChunkIdsPlugin and should have removed NamedModulesPlugin at that point but left them both in.

This is where our new custom "HashedChunkIdsPlugin" was added just-boris@f0fccb0#diff-c4777e791f64fbb6c82255341b381dab but NamedModulesPlugin wasn't removed.

I'm a bit fuzzy about what webpack would be doing here but perhaps NamedModulesPlugin isn't even being used?

Maybe?

I want to get off this onto webpack 3 where it seems the situation is mildly more sane.

[jquense]

I'm thinking a bit about the v2 branch where the hashed chunk Ids plugin was removed because it didn't work anymore and we do lean on the named module and chunk plugins for saner LTC, a la https://medium.com/webpack/predictable-long-term-caching-with-webpack-d3eee1d3fa31

[KyleAMathews]

Yeah the hashed chunk ids plugin was just for webpack v1.

[mperkh]

Tested removal of NamedModulesPlugin and my builds are clean now and it didnt cause any issues.

[just-boris]

@KyleAMathews good to know that somehow soon-ish we will have a newer version with Webpack 3, where this issue will go away.

But how about merging this, as it resolves the issue immediately, without additional problems?

[KyleAMathews]

Merging and releasing 🎉

[just-boris]

Thank you!

[jlengstorf]

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