Inline deep dependencies for entry points

[guybedford]

As described in #2071, this will minimize the latency waterfall problem for deep chunkings chains, making code splitting workflows faster.

Note this will likely have merge conflicts with #2068. Either can be merged first and I'll fix up the conflicts for the other.

[lukastaegert]

That's a fantastic improvement, great idea!

Two things:

• I added a minor suggestion but it is more cosmetic than anything
• I think that this should preserve execution order between modules but since you are definitely the expert here, just wondering if you are sure and have checked this

[lukastaegert]

As this if-else is basically a preparation step for getChunkDependencyDeclarations with the sole purpose of adding some additional dependencies to this.dependencies, I would suggest extracting it into a separate private method, e.g. addAdditionalDependencies or addDerivedDependencies or whatever rings best with you.
Then I would suggest to call this method not from within getChunkDependencyDeclarations but directly from getModuleDeclarations. Thus it is immediately visible that this public method has a side-effect on a chunk's dependencies (which may or may not be helpful for future refinements)

[guybedford]

Thanks for review here - I've included the change.

Yes, execution order will definitely remain invariant with this change!

For example:

a.js

import 'b';

b.js

import 'c';
import 'd';
import 'e';

Can have a.js rewritten as import 'b'; import 'c'; import 'd'; import 'e'; or import 'b'; import 'e'; import 'd'; import 'c'; and will retain the same execution order as what matters is the first-visited pre-order traversal only.

[lukastaegert]

as what matters is the first-visited pre-order traversal only.

💡Ah, that makes sense, thanks!

[lukastaegert]

👍