From 7cd807e5883736e1eeddb091b5774ee95af29869 Mon Sep 17 00:00:00 2001
From: Vincent Laporte <Vincent.Laporte@gmail.com>
Date: Fri, 2 Jun 2023 10:07:13 +0200
Subject: [PATCH] ocamlPackages.pgocaml: fix for OCaml 5.0

---
 .../ocaml-modules/pgocaml/default.nix          | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/pkgs/development/ocaml-modules/pgocaml/default.nix b/pkgs/development/ocaml-modules/pgocaml/default.nix
index 22ef94af92e1..76b97103d667 100644
--- a/pkgs/development/ocaml-modules/pgocaml/default.nix
+++ b/pkgs/development/ocaml-modules/pgocaml/default.nix
@@ -1,7 +1,9 @@
-{ lib, fetchFromGitHub, buildDunePackage
-, calendar, csv, hex, ppx_deriving, ppx_sexp_conv, re, rresult, sexplib
+{ lib, fetchFromGitHub, fetchpatch, buildDunePackage, ocaml
+, calendar, camlp-streams, csv, hex, ppx_deriving, ppx_sexp_conv, re, rresult, sexplib
 }:
 
+let with-camlp-streams = lib.optional (lib.versionAtLeast ocaml.version "5.0"); in
+
 buildDunePackage rec {
   pname = "pgocaml";
   version = "4.3.0";
@@ -12,10 +14,16 @@ buildDunePackage rec {
     hash = "sha256-W1fbRnU1l61qqxfVY2qiBnVpGD81xrBO8k0tWr+RXMY=";
   };
 
-  minimalOCamlVersion = "4.08";
-  duneVersion = "3";
+  # Compatibility with OCaml ≥ 5.0
+  patches = with-camlp-streams (fetchpatch {
+    url = "https://github.com/darioteixeira/pgocaml/commit/906a289dc57da4971e312c31eedd26d81e902ed5.patch";
+    hash = "sha256-/v9Jheg98GhrcD2gcsQpPvq7YiIrvJj22SKvrBRlR9Y=";
+  });
 
-  propagatedBuildInputs = [ calendar csv hex ppx_deriving ppx_sexp_conv re rresult sexplib ];
+  minimalOCamlVersion = "4.08";
+
+  propagatedBuildInputs = [ calendar csv hex ppx_deriving ppx_sexp_conv re rresult sexplib ]
+  ++ with-camlp-streams camlp-streams;
 
   meta = with lib; {
     description = "An interface to PostgreSQL databases for OCaml applications";