[fix] added "browser" conditional to "exports" in package.json

[bf-software]

fixes: #6877

This will allow electron renderers to avoid loading ssr.mjs when importing svelte and instead load index.mjs like a normal browser would. Electron renderers are like normal browsers, but they also can access node functions, which is why both the "node", and "browser" conditionals are present when resolving module names using package.json's "exports" feature.

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[bluwy]

From the linked issue, I think this is a fair change to support webpack + electron, without having an "electron" condition. (or maybe we want that?) (not needed)

[benmccann]

lgtm. Though I do somewhat wonder if we shouldn't change the condition from browser to electron to clarify why the condition is there because otherwise it doesn't make much sense as there aren't many platforms that would match both browser and node

[dummdidumm]

I'm not sure if this would work - do the bundler in question and the elctron loader search for a electron condition in exports?

[bluwy]

For webpack, it will use the electron condition for electron builds, according to https://webpack.js.org/guides/package-exports/#target-environment

[bf-software]

Please also note that electron uses at minimum 2 different processes for a single electron app: the main process and 1 or more renderer processes. In Windows for example, you start your app by running electron.exe yourscript.js. This is the main process and is basically just like running node.exe your-script.js -- meaning it has no DOM access, it only has node access. Then your-script.js can launch additional electron.exe your-window.html processes. These are the renderer processes that present your app's GUI to the user--and these have both node and DOM (browser) access. So when targeting the renderer, we definitely want Svelte to act like its in a browser (because it is). But, it's probably possible for someone to use Svelte in the main process with server side rendering, like maybe if they were converting an SSR web app to a desktop app? So in that case, when targeting the main process, we would want Svelte to act like it's being used in a node server. In both cases, electron is present in the conditionals.

[bluwy]

Thanks for the explanation @bf-software. In that case we should stick with browser then.