Minify JSON

[DeMoorJasper]

closes #400 closes #399

[kzc]

Should check the minify() result for error.

https://github.com/mishoo/UglifyJS2/tree/harmony#api-reference

[kzc]

for example:

parcel/src/transforms/uglify.js

Lines 25 to 28 in 68258b1

	let result = minify(code, options);
	if (result.error) {
	throw result.error;
	}

[brandon93s]

parcel/src/transforms/uglify.js

Lines 25 to 36 in 065a49e

	let result = minify(code, options);
	if (result.error) {
	throw result.error;
	}
	// Log all warnings
	if (result.warnings) {
	result.warnings.forEach(warning => {
	// TODO: warn this using the logger
	console.log(warning);
	});
	}

[brandon93s]

Are we intentionally skipping any custom config for JSON?

parcel/src/transforms/uglify.js

Line 10 in 065a49e

let customConfig = await config.load(asset.name, ['.uglifyrc']);

Seems a lot of this could be consolidated with the uglify transform.

[kzc]

result.warnings is not interesting in parsing JS expressions - result.error is sufficient as it's a binary pass/fail operation. The warnings apply to the uglify compressor which is not applicable here.

[DeMoorJasper]

@brandon93s i don't think anyone would want to change this behaviour, as it just removing some quotes and whitespace

[DeMoorJasper]

@kzc i'll throw the errors, forgot about those

[devongovett]

Refactored slightly to make JSONAsset not inherit from JSAsset anymore. Seems like that had the potential to break more things than it helped with as we add more stuff to JSAsset that doesn't apply to JSON.