fix(electron-updater): relax multipart boundary regex to allow no space

[fleabagneverdie]

Background

Currently, electron-updater uses a regex to detect multipart responses from the server when performing segmented downloads. The regex requires a space before the boundary parameter:

/^multipart\/.+?\s*;\s*boundary=(?:"([^"]+)"|([^\s";]+))\s*$/i

According to the HTTP standard, the space before boundary is optional. Servers that omit the space will fail detection, causing the updater to incorrectly treat the response as non-multipart, which can disable segmented downloads.

What this PR does

Updates the regex to allow the boundary parameter to appear immediately after the semicolon, removing the requirement for a space.

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🦋 Changeset detected

Latest commit: a4abb50

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
electron-updater	Patch

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[mmaietta]

Does this need to be adjusted as well?

electron-builder/packages/electron-updater/src/differentialDownloader/multipleRangeDownloader.ts

Line 49 in 08773af

ranges += `${task.start}-${task.end - 1}, `

[fleabagneverdie]

Maybe not, but adding or omitting spaces after commas in the Range header doesn’t affect functionality. Servers like Alibaba Cloud can recognize both formats, so it's not strictly necessary to add spaces.

[mmaietta]

Was just checking this further again. Isn't \s* the same as [\s]*? * is zero or unlimited, so the former version should be the same effectively pre/post-codechange. Right? I might just be needing some coffee though

[fleabagneverdie]

After checking, I found that a PR was already submitted 6 months ago with the relevant changes. However, the npm package hasn’t been updated yet, so no further action is needed on this. My apologies for the confusion.