Lwt 4.1.0: concurrency library, now under MIT license

[aantron]

The main purpose of this release is that it is the first one under the MIT license.

From the changelog:

Additions

• Change license to MIT (Change license to MIT ocsigen/lwt#560).
• Lwt_fmt, an Lwt-aware version of Format (Lwt_fmt ocsigen/lwt#548, Gabriel Radanne).
• Lwt_io.establish_server_with_client_socket (Lwt_io.establish_server (TCP servers): expose client socket to connection-handling callback ocsigen/lwt#586).

Bugs fixed

• Lwt_stream.iter_n: rename ?max_threads argument to ?max_concurrency (Use max_concurrency rather than max_threads ocsigen/lwt#581, Hezekiah Carty).
• PPX: reject match expressions that have only exception cases (Ppx: refuse match cases with only exception cases ocsigen/lwt#597, Raphaël Proust).

Miscellaneous

• Improvements to Lwt_pool docs (Improve lwt_pool introduction docs with examples ocsigen/lwt#575, Bobby Priambodo).
• Restore all PPX tests (Make coverage tests use development versions of lwt and lwt_ppx ocsigen/lwt#590, Jess Smith).

[camelus]

❗ opam-lint warnings da0952a

• lwt.4.1.0 has some warnings:

  • warning 41: Some packages are mentionned in package scripts of features, but there is no dependency or depopt toward them:
    "camlp4", "lwt_camlp4", "lwt_log", "lwt_ppx"

• These packages passed lint tests: lwt_ppx.1.2.1

---

✅ Installability check (9031 → 9033)

• new installable packages (2): lwt.4.1.0 lwt_ppx.1.2.1

[aantron]

I constrained the following packages with ocaml-version < "4.06.0", because they are not -safe-string-compatible:

amqp-client 1.0.1 and 1.0.2, bencode-rpc 1.0, bencode 0.2, dht 0.1.3 lwt-binio 0.2.1 (cc @hcarty), xenctrl (cc @andyhhp), ocplib-concur (cc @lefessan), xen-evtchn 1.0.1, 1.0.3, 1.0.4, 1.0.5, zbar (cc @vbmithr)

statsd-client assumes that Unix.socket and Lwt_unix.socket have compatible type signatures, but Unix.socket gained a ?cloexec argument in 4.05.0, while Lwt_unix.socket doesn't have it (yet?). I constrained statsd-client to require OCaml < 4.05.0. cc @mjambon, @mfp.

The following failed with bad checksums:

brotli 1.0, brotli 1.1, mirage 2.5.0

I didn't do anything about these.

FTR, none of these are due to Lwt. This is just to clean up the revdeps build.

[aantron]

I suggest merging this. There were no failures due to Lwt 4.1.0 in the original CI build, and the build is not running since I added the constraints, because some of the constrained packages have broken builds themselves.

We could split this up into two PRs to get a rebuild of Lwt against the new constraints, but I'd rather not do that. I think we will only find a few more packages that are not -safe-string-compatible, which can be done later by another package or a future release of Lwt.

[avsm]

Agreed. Thanks for doing all the revdeps work! By tomorrow, opam ci status should show any revdep or safe-string fallout with the results of this merged PR, which should help with subsequent PRs.

[aantron]

Thanks!