ref(hub): Move @sentry/hub code to @sentry/core

[timfish]

Closes #5665

This PR:

• Moves all of the @sentry/hub code files to @sentry/core
• Changes @sentry/hub to a stub that re-exports the same types from @sentry/core
  • @sentry/hub now only depends on @sentry/core
• Switches internal imports @sentry/hub -> @sentry/core
  • Removes @sentry/hub as a dependency from packages
• Fixes all the mocks/spys/imports in tests
• Leaves the @sentry/hub tests where they are for now

Surprisingly this results in a 159 byte increase in minified bundle size!

I've compared the type exports from @sentry/hub from before and after this PR and the exports match so it looks like this isn't a breaking change 😬

[AbhiPrasad]

We merged in #5873, which prob requires a more tricky rebase.

[timfish]

Should we be marking all @sentry/hub exports as Deprecated - Moved to @sentry/core. @sentry/hub will be removed in v8?

[AbhiPrasad]

For future readers: We'll save deleting @sentry/hub for the next major version, this just sets us up to do further refactors to work toward truly platform agnostic packages.

[AbhiPrasad]

Should we be marking all @sentry/hub exports as Deprecated - Moved to @sentry/core. @sentry/hub will be removed in v8?

Good idea! Let's do that.

[timfish]

Since the exports in @sentry/hub are just re-exports of external types, the only way to mark them as deprecated is to re-declare them as const and then mark with jsdoc like:

export { getCurrentHub as getCurrentHubCore } from '@sentry/core';

/**
 * @deprecated This export has moved to @sentry/core. The @sentry/hub package will be removed in v8 
 */
const getCurrentHub = getCurrentHubCore;

export { getCurrentHub }

[timfish]

Ok, I think this is now good to go.

I couldn't mark Scope and Hub as deprecated like above because setting them as a const turns them into a value that can't then be used as a type!

[lobsterkatie]

I couldn't mark Scope and Hub as deprecated like above because setting them as a const turns them into a value that can't then be used as a type!

@timfish, since they're classes, could you do

import { Hub as CoreHub } from '@sentry/core';

/**
 * @deprecated This export has moved to @sentry/core. The @sentry/hub package will be removed in v8 
 */
export class Hub extends CoreHub { };

?

[timfish]

It does leave me with a strange feeling that it is somehow exporting a different type to before but my logical side says that it's totally fine! 🙃

[AbhiPrasad]

Can we move the tests in another PR?

Let's try to get this released on Monday alongside the NextJS experimental flag switch

[timfish]

Leaving the tests in hub was instrumental in ensuring that there were no breaking changes in @sentry/hub exports.

Safe to move then now?

[AbhiPrasad]

Leaving the tests in hub was instrumental in ensuring that there were no breaking changes in @sentry/hub exports.

Ahhh great point, then let's keep them until we do the actual deletion during the major.