Restore hashing of all CSS file names (#1716)

[fivemru]

Explicitly use hash in rollup-plugin-css-chunks:

chunkFileNames: '[name]-[hash].css',
entryFileNames: '[name]-[hash].css'

fix #1716

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Tests

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[benmccann]

I would expect this to be specified in Rollup's output.entryFileNames and then all plugins should use that instead of needing to specify it on a per-plugin basis

[fivemru]

I would expect this to be specified in Rollup's output.entryFileNames and then all plugins should use that instead of needing to specify it on a per-plugin basis

The point is that config.client.output() contains the .js extension in the entryFileNames and chunkFileNames fields.

sapper/src/config/rollup.ts

Line 20 in 3c01d93

entryFileNames: '[name].[hash].js',

Just replace .js with .css I think it will not be completely predictable behavior.

Now the css file names are completely dependent on the defaults in rollup-plugin-css-chunks, due to their change in version 2.0.0 this bug occurred.

As noted at

sapper/src/core/create_compilers/RollupCompiler.ts

Line 163 in 3003e98

// TODO this is hacky. refactor out into an external rollup plugin

it is most likely correct to put this in an external plugin.

This pull request simply restores the behavior of version 0.28.10.

[benmccann]

Ok, makes sense I guess

[istarkov]

Please release.