chore: bump semver to 7.0.0

[JLHwung]

Q	A
Any Dependency Changes?	semver is bumped to 7.0.0
License	MIT

Note that for most users we are already shipping an instance of semver@7.0.0 via core-js-compat. Unfortunately we have to pin semver to 7.0.0 because 7.1.0 will break yarn users on node.js 6.

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[merceyz]

Unfortunately we have to pin semver to 7.0.0 because 7.1.0 will break yarn users on node.js 6.

Could use constraints to make sure that is documented and enforced across the repo

[kaicataldo]

Looks like there are merge conflicts now - should we wait to evaluate this until it's all fixed up?

[JLHwung]

Could use constraints to make sure that is documented and enforced across the repo

Good idea. I tend to address that in another PR that focused on yarn constraints.

[JLHwung]

@kaicataldo Resolved conflicts.

[nicolo-ribaudo]

With assumptions this will be easier 😂

[argshook]

Howdy, just wanted to inform that using semver pinned to 7.0.0 causes issues when @babel/core is required within webpack.

in our case we have a code editor running in browser, which uses babel parser. After upgrading babel to 7.13.1 we also got semver@7.0.0

looks like semver themselves are aware of this issue npm/node-semver#306 and since then has fixed it.

maybe consider using semver@7.1.2?

[nicolo-ribaudo]

We can't upgrade because ^7.1.0 contains a breaking change that would be reflected to our users, but I would happily accept a PR to downgrade to ^6 (even if "Babel supports being bundled" is not really a design goal).

[EricMCornelius]

@nicolo-ribaudo - can you elaborate? What breaking change in semver ^7.1.0 is going to cause the issue?

Bundling babel is very useful from a performance perspective - as observed here: #9575

The reduction in startup time and memory consumption for our CI build as a result are significant - would be a shame to lose the ability.

[merceyz]

@nicolo-ribaudo - can you elaborate? What breaking change in semver ^7.1.0 is going to cause the issue?

See this thread npm/node-semver@d61f828#r36469180

[EricMCornelius]

@merceyz - thanks.