[RFC] Improve compatibility with legacy versions

[clue]

Because why not… :-)

Now more seriously: This project is a low level lib that is used as a building block for quite a few higher level abstractions on top of it. As such, compatibility (even with significantly outdated versions) is a major concern to me.

Note that I'm not suggesting putting significant amount of work into this. The patch is already here and, personally, I see little harm in supporting this.

Also note that I'm not suggesting we need to keep support indefinitely. Should this ever turn out to be a burden in the future, e.g. because we actually require any new language features or some external lib, then I'm all for dropping support again.

[WyriHaximus]

What about code that typehints against DuplexStreamInterface? Considering to be a BC tbh.

[clue]

This actually amends #26 which in turn amends #14.

The documentation always stated this returns a Stream instance, never an instance implementing DuplexStreamInterface.

FWIW: This repo currently targets react/stream:0.4.*, while this interface has only been added with v0.4.2, so even if we decide not to support legacy versions, this is still a bug that needs fixing. If you happen to have v0.4.2+, then Stream implements the DuplexStreamInterface.

As such, I do not consider this a BC break.

Even despite this, this PR should probably be part of the v0.5.0 milestone, which already includes a (minor) BC break anyway.

[WyriHaximus]

Wasn't aware DuplexStreamInterface was added later in 0.4.x, so yeah it isn't a BC break imo :).

[cboden]

Not quite sure what it was but I get a failing unit test when merging this into master (even after resolving the merge conflict).

[clue]

Not quite sure what it was but I get a failing unit test when merging this into master (even after resolving the merge conflict).

I've just rebased this now that #52 is in and all tests are working just fine 👍 What error are you seeing?

[cboden]

Rebase looks good. I must have messed up the merge on my end before