Rollup bundle

[realityking]

What issue does this pull request resolve?

As mentioned in #1526 (comment), this changed the build process for the bundles to create source maps that are based of the original Typescript files. As an added advantage, they're also much smaller!

I'm including again the change not to ship source maps as it's now unambiguous that the source maps are not needed for the browser bundles.

What changes did you make?

• Replace browserify with rollup
• Remove scripts/bundle.js with a rollup config file
• Builds are directly from ts files, so npm run bundle can be run without first running npm run build
• Disabled generation of source maps for the dist build to save the size in the npm package. (see Smaller package #1526 for prior discussion)

Is there anything that requires more attention while reviewing?

Overview of size changes:

File	master	rollup	change
ajv2019.bundle.js	280K	268K	-4.3%
ajv2019.min.js	136K	108K	-20.6%
ajv2019.min.js.map	180K	208K	+15.5%
ajv7.bundle.js	264K	252K	-4.5%
ajv7.min.js	124K	100K	-19.4%
ajv7.min.js.map	168K	200K	+19%
ajvJTD.bundle.js	256K	240K	-6.25%
ajvJTD.min.js	120K	96K	-20%
ajvJTD.min.js.map	168K	200K	+19%

The source maps are quite a bit bigger but the actual code files are a lot smaller.

[epoberezkin]

Thank you!

[realityking]

I pushed a small fix. I had omitted removing the bundle folder before building bundles.

[epoberezkin]

@realityking the main reason I didn't merge yet was that I was wondering whether there could be the contexts where source maps are needed?

See: #1532

Could we maybe do it in two steps:

1. release rollup bundling (without removing source maps from npm)
2. make a patch release that does only source map removal, so that if something is broken I can release the next patch reverting it.

In v9 I would also remove typescript source from npm, so that if somebody needs to recompile they would have to use GitHub, but it's relatively rare to justify having it all in npm... Currently there are dependencies on source.

[epoberezkin]

Also, rollup has an added benefit of warning about circular dependencies that was quite an effort to remove, so I'd rather they don't creep back in... Is it maybe possible to fail in case of circular dependencies warnings?

[realityking]

I rebased this PR and dropped source map commit.

Also, rollup has an added benefit of warning about circular dependencies that was quite an effort to remove, so I'd rather they don't creep back in... Is it maybe possible to fail in case of circular dependencies warnings?

I'm not sure what you're asking for. Do you want the build to fail if there's a circular dependency warning? Rollup has --failAfterWarnings but that will fail the build for any warning. If that not desired a custom script would have to be build to check the warnings on only fail for specific ones.

[epoberezkin]

If that not desired a custom script would have to be build to check the warnings on only fail for specific ones.

I see... No problem, at least the warnings would be more visible.