--no-source-maps doesn't work if source maps are cached

[DeMoorJasper]

🐛 bug report

Continuation of #2079

I am still seeing this issue on parcel-bundler 1.11.0.

1. If I build with source maps, then rm -r dist/ and build with --no-source-maps, then I still get source maps in dist/
2. If I then rm -r .cache/ dist/ to remove both the cache and dist and build again with --no-source-maps, then I get it without source maps

./node_modules/.bin/parcel --version
1.11.0

by @mrcoles

🎛 Configuration (.babelrc, package.json, cli command)

parcel build index.js --no-source-maps

🤔 Expected Behavior

should not package sourcemaps

😯 Current Behavior

Packages cached sourcemaps

💁 Possible Solution

check if sourcemaps should be made in packaging

🌍 Your Environment

Software	Version(s)
Parcel	1.11
Node	10
npm/Yarn	latest
Operating System	OS X

[mischnic]

@DeMoorJasper This is the very last issue I have with the CSS source maps PR, I also proposed two possible solutions, but I'm not sure which is better: #2489 (comment)

[DeMoorJasper]

@mischnic not sure if always creating a sourcemaps on asset lvl is a good idea, it will impact performance on builds and it’s unlikely someone will change between no sourcemaps and sourcemaps a lot.
Only outputting sourcemaps bundles if sourcemaps are enable seems like the best idea, but the flag shouldn’t invalidate cache afaik as packaging isn’t cached

_{Sent with GitHawk}

[mischnic]

not sure if always creating a sourcemaps on asset lvl is a good idea, it will impact performance on builds and it’s unlikely someone will change between no sourcemaps and sourcemaps a lot.

This would mean: invalidate the cache based on the flag because assets are cached

but the flag shouldn’t invalidate cache afaik as packaging isn’t cached

A contradiction?

[DeMoorJasper]

@mischnic yeah just realised that switching from no sourcemaps to sourcemaps would have unexpected results of sourcemaps flag is not part of cache. Thinking about that it would probably need to invalidate I guess, depends on how much impact sourcemaps would have on performance. If it has little to no impact it might be worth it to always generate sourcemaps and not package them based on flag

_{Sent with GitHawk}

[mischnic]

depends on how much impact sourcemaps would have on performance.

	w/ sourcemaps	w/o sourcemaps
react boilerplate	6.57s	5.64s
reproduction from #2685	127.62s	72.00s

Opting for invalidation (to keep these values).

[nVitius]

@mischnic @devongovett Can you guys expand on why this issue was closed? It doesn't make sense to have an option to not build source maps and then proceed to include them anyways. In my case, I want source maps to be generated for development. But I don't want them to be generated for my build that goes out to production as they essentially double my app size. I don't see why I should have to clear the cache every time I want to make my production build. Am I just thinking about this the wrong way?