Tabs vs spaces and single vs double quotes in existing files
#118
Development PR
Closes #44 Closes #118 Relates #100
This basically duplicates #100 at this point. See #100 for up and downsides of this approach.
I was initially intending to get rid of a lot more dependencies (like the dependencies for handling html) and use svelte-ast-print instead, but this was opening too many issues at the same time. That's why I opted to "only" switch to acorn and esrap here, the rest can be done later.
Relevant PR's / issues
- Rich-Harris/esrap#18
- Rich-Harris/esrap#19
- sveltejs/esrap#44
- sveltejs/esrap#47
- sveltejs/esrap#51
- sveltejs/esrap#45
- sveltejs/esrap#52
Benefits
- closer to other tools in the
svelteecosystem - Faster bundling (~33% speed improvement locally from 4s to 3s, probably more with #371)
- Smaller bundle (locally 2.6MB vs 3.6MB)
- more consistent formatting than the strange things we sometimes experienced with
recast - we are in full control of the printing, as we can control
esrap
Downsides
- Our custom typing for
TSEstreeas no good public alternative exists, that matchesacorns output. We do have@typescript-eslint/typesbut that was just the one with the smallest pain points. Still exploring other options.
Issue
We now default to tabs and single quotes in new files
We have guessIndentString, but it's only used for JSON. Can we use guessIndentString for JS/TS as well? Barring that, can we set the formatting for existing files to match the default for new files?
Info
I don't think this is possible in a reasonable manner. If this would work then as post-processing step after serializing the ast. In that case i think we should rather spend effort in solving the problem once and for all via #100
Wouldn't we need to do roughly the same thing in either case? Whether we're using recast or esrap to print the file, I'd expect we would need to tell it whether to use tabs/spaces and single/double quotes. Or does esrap have built-in detection for that already?
Fair point, looks like you are right. esrap seems to always use tabs and single quotes. Does not look like it has any detection for it, or any options regarding this...
Interesting. Maybe we can do the same and see if people complain. If so, then we'll know we need to add an option to esrap