restore lwt_ppx compatible with ocaml4

raphael-proust · raphael-proust · commit e746d4d3adc6 · 2025-08-22T09:52:24.000+02:00
diff --git a/.github/workflows/workflow.yml b/.github/workflows/workflow.yml
@@ -49,12 +49,12 @@ jobs:
         run: |
           case ${{ matrix.ocaml-compiler }} in
             "4.08"|"4.09"|"4.10"|"4.11"|"4.12"|"4.13"|"4.14"|"5.0")
-              echo "ppx=false"
-              echo "ppx=false" >> "$GITHUB_OUTPUT"
+              echo "letppx=false"
+              echo "letppx=false" >> "$GITHUB_OUTPUT"
               ;;
             "5.1"|"5.2"|"5.3")
-              echo "ppx=true"
-              echo "ppx=true" >> "$GITHUB_OUTPUT"
+              echo "letppx=true"
+              echo "letppx=true" >> "$GITHUB_OUTPUT"
               ;;
             *)
               printf "unrecognised version %s\n" "${{ matrix.ocaml-compiler }}";
@@ -73,20 +73,20 @@ jobs:
       - run: opam install conf-libev
         if: ${{ matrix.libev == true }}
 
-      - run: opam install ./lwt.opam ./lwt_react.opam ./lwt_retry.opam --deps-only --with-test
+      - run: opam install ./lwt.opam ./lwt_react.opam ./lwt_retry.opam ./lwt_ppx.opam --deps-only --with-test
 
-      - run: opam install ./lwt_ppx.opam --deps-only --with-test
-        if: ${{ fromJSON(steps.configppx.outputs.ppx) }}
+      - run: opam install ./lwt_ppx__ppx_let_tests.opam --deps-only --with-test
+        if: ${{ fromJSON(steps.configppx.outputs.letppx) }}
 
       - run: opam exec -- dune build --only-packages lwt,lwt_react,lwt_retry
 
-      - run: opam exec -- dune build --only-packages lwt_ppx
-        if: ${{ fromJSON(steps.configppx.outputs.ppx) }}
+      - run: opam exec -- dune build --only-packages lwt_ppx__let_ppx_tests
+        if: ${{ fromJSON(steps.configppx.outputs.letppx) }}
 
-      - run: opam exec -- dune runtest --only-packages lwt,lwt_react,lwt_retry
+      - run: opam exec -- dune runtest --only-packages lwt,lwt_react,lwt_retry,lwt_ppx
 
-      - run: opam exec -- dune runtest --only-packages lwt_ppx
-        if: ${{ fromJSON(steps.configppx.outputs.ppx) }}
+      - run: opam exec -- dune runtest --only-packages lwt_ppx__let_ppx_tests
+        if: ${{ fromJSON(steps.configppx.outputs.letppx) }}
 
   lint-opam:
     runs-on: ubuntu-latest
diff --git a/dune-project b/dune-project
@@ -1,4 +1,4 @@
-(lang dune 2.7)
+(lang dune 3.15)
 
 (name lwt)
 
@@ -27,11 +27,20 @@
  (name lwt_ppx)
  (synopsis "PPX syntax for Lwt, providing something similar to async/await from JavaScript")
  (depends
-  (ocaml (>= 5.1))
+  (ocaml (>= 4.08))
   (ppxlib (>= 0.36))
-  (ppx_let (and :with-test (>= v0.17.1)))
   (lwt (>= 5.7))))
 
+(package
+ (name lwt_ppx__ppx_let_tests)
+ (synopsis "DO NOT RELEASE! only for testing let_ppx")
+ (license NOTFORRELEASE) ;; trap for opam-repo ci
+ (allow_empty)
+ (depends
+  (ocaml (>= 5.1))
+  (ppx_let (and :with-test (>= v0.17.1)))
+  lwt_ppx))
+
 (package
  (name lwt_react)
  (synopsis "Helpers for using React with Lwt")
diff --git a/lwt.opam b/lwt.opam
@@ -20,7 +20,7 @@ homepage: "https://github.com/ocsigen/lwt"
 doc: "https://ocsigen.org/lwt"
 bug-reports: "https://github.com/ocsigen/lwt/issues"
 depends: [
-  "dune" {>= "2.7"}
+  "dune" {>= "3.15"}
   "ocaml" {>= "4.08"}
   "cppo" {build & >= "1.1"}
   "ocamlfind" {dev & >= "1.7.3-1"}
diff --git a/lwt_ppx.opam b/lwt_ppx.opam
@@ -11,10 +11,9 @@ homepage: "https://github.com/ocsigen/lwt"
 doc: "https://ocsigen.org/lwt"
 bug-reports: "https://github.com/ocsigen/lwt/issues"
 depends: [
-  "dune" {>= "2.7"}
-  "ocaml" {>= "5.1"}
+  "dune" {>= "3.15"}
+  "ocaml" {>= "4.08"}
   "ppxlib" {>= "0.36"}
-  "ppx_let" {with-test & >= "v0.17.1"}
   "lwt" {>= "5.7"}
   "odoc" {with-doc}
 ]
diff --git a/lwt_ppx__ppx_let_tests.opam b/lwt_ppx__ppx_let_tests.opam
@@ -0,0 +1,33 @@
+# This file is generated by dune, edit dune-project instead
+opam-version: "2.0"
+synopsis: "DO NOT RELEASE! only for testing let_ppx"
+maintainer: [
+  "Raphaël Proust <code@bnwr.net>" "Anton Bachin <antonbachin@yahoo.com>"
+]
+authors: ["Jérôme Vouillon" "Jérémie Dimino"]
+license: "NOTFORRELEASE"
+homepage: "https://github.com/ocsigen/lwt"
+doc: "https://ocsigen.org/lwt"
+bug-reports: "https://github.com/ocsigen/lwt/issues"
+depends: [
+  "dune" {>= "3.15"}
+  "ocaml" {>= "5.1"}
+  "ppx_let" {with-test & >= "v0.17.1"}
+  "lwt_ppx"
+  "odoc" {with-doc}
+]
+build: [
+  ["dune" "subst"] {dev}
+  [
+    "dune"
+    "build"
+    "-p"
+    name
+    "-j"
+    jobs
+    "@install"
+    "@runtest" {with-test}
+    "@doc" {with-doc}
+  ]
+]
+dev-repo: "git+https://github.com/ocsigen/lwt.git"
diff --git a/lwt_react.opam b/lwt_react.opam
@@ -10,7 +10,7 @@ homepage: "https://github.com/ocsigen/lwt"
 doc: "https://ocsigen.org/lwt"
 bug-reports: "https://github.com/ocsigen/lwt/issues"
 depends: [
-  "dune" {>= "2.7"}
+  "dune" {>= "3.15"}
   "ocaml" {>= "4.08"}
   "cppo" {build & >= "1.1"}
   "lwt" {>= "3.0"}
diff --git a/lwt_retry.opam b/lwt_retry.opam
@@ -10,7 +10,7 @@ homepage: "https://github.com/ocsigen/lwt"
 doc: "https://ocsigen.org/lwt"
 bug-reports: "https://github.com/ocsigen/lwt/issues"
 depends: [
-  "dune" {>= "2.7"}
+  "dune" {>= "3.15"}
   "ocaml" {>= "4.08"}
   "lwt" {>= "5.3"}
   "odoc" {with-doc}
diff --git a/test/ppx_let/dune b/test/ppx_let/dune
@@ -1,6 +1,7 @@
 (test
  (name test)
- (package lwt_ppx) ;; technically not part of lwt_ppx, but we want it tested and the dependency to ppxlib is already there
+ (package lwt_ppx__ppx_let_tests)
+ (build_if %{lib-available:ppx_let})
  (preprocess
   (pps ppx_let))
  (libraries lwt lwt.unix))
