build: Speed up playground build

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As discussed in #1836 (comment)

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This works quite well, and solves most of the runtime issues with wasm-pack (but not the dependency issues). We could postpone #1836 (comment). And remove the recent additional tasks around caching the playground etc.

But unfortunately we get another stack size issue!

Failed to decode custom "name" section @20041605; ignoring (Maximum call stack size exceeded).

So maybe we look at this again after #2908 is solved...

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Since #2908 seems to be solved, we no longer the stack overflow above.

But we get a different error — Module parse failed: Unexpected section: 0x9

ERROR in ../../bindings/prql-js/dist/bundler/prql_js_bg.wasm
Module parse failed: Unexpected section: 0x9
You may need an appropriate loader to handle this file type, currently no loaders are configured to process this file. See https://webpack.js.org/concepts#loaders
Error: Unexpected section: 0x9
    at new CompileError (/Users/maximilian/workspace/prql/web/playground/node_modules/@webassemblyjs/helper-api-error/lib/index.js:40:109)
    at parseSection (/Users/maximilian/workspace/prql/web/playground/node_modules/@webassemblyjs/wasm-parser/lib/decoder.js:1329:76)
    at Object.decode (/Users/maximilian/workspace/prql/web/playground/node_modules/@webassemblyjs/wasm-parser/lib/decoder.js:1712:25)
    at decode (/Users/maximilian/workspace/prql/web/playground/node_modules/@webassemblyjs/wasm-parser/lib/index.js:248:21)
    at WebAssemblyParser.parse (/Users/maximilian/workspace/prql/web/playground/node_modules/webpack/lib/wasm-async/AsyncWebAssemblyParser.js:48:19)
    at /Users/maximilian/workspace/prql/web/playground/node_modules/webpack/lib/NormalModule.js:1089:26
    at processResult (/Users/maximilian/workspace/prql/web/playground/node_modules/webpack/lib/NormalModule.js:802:11)
    at /Users/maximilian/workspace/prql/web/playground/node_modules/webpack/lib/NormalModule.js:862:5
    at /Users/maximilian/workspace/prql/web/playground/node_modules/loader-runner/lib/LoaderRunner.js:407:3
    at iterateNormalLoaders (/Users/maximilian/workspace/prql/web/playground/node_modules/loader-runner/lib/LoaderRunner.js:233:10)
 @ ../../bindings/prql-js/dist/bundler/prql_js.js 3:0-42 5:15-19
 @ ./src/workbench/Workbench.js 5:0-45 71:12-24 98:13-28 104:13-26
 @ ./src/app/App.js 5:0-47 66:37-46
 @ ./src/index.js 8:0-28 13:33-36

Searching for this gives a couple of issues: rustwasm/wasm-pack#1050 & webpack/webpack#14087. These both reference https://github.com/wasm-tool/wasm-pack-plugin, which we don't use¹.

Overall I'm not experienced enough at JS to do this quickly or well, but if someone wants to investigate further, that'd be welcome.

Footnotes

1. though maybe we could? It looks like one advantage is that it'll identify when we need to recompile the rust, rather than recompiling each time, maybe solving some of the symptoms of https://github.com/PRQL/prql/issues/1836. If anyone wants to have a go, that'd be interesting.) ↩

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This now works great! I think because of the move to vite — courtesy of @vanillajonathan .

So I'm merging. task run-playground is down to 7 seconds, including recompilation, from ~40 seconds. Note that it does make the local playground experience slightly-but-noticeably laggier. So if that's a concern, run without the --profile=dev. This only affects local development, not the published version.