fix(x-compilation): take the default findlib path context into account

Signed-off-by: Antonio Nuno Monteiro <[email protected]>

src/dune_rules/context.ml

@@ -299,26 +299,23 @@ module Build_environment_kind = struct
           | None -> Unknown)))
 
   let findlib_paths ocamlfind ~kind ~context ~findlib_toolchain ~env ~dir =
-    match query ~kind ~findlib_toolchain ~env with
-    | Cross_compilation_using_findlib_toolchain _toolchain -> (
-      match ocamlfind with
-      | None ->
-        Code_error.raise
-          "Could not find ocamlfind in PATH or an environment variable \
-           OCAMLFIND_CONF"
-          [ ("context", Context_name.to_dyn context) ]
-      | Some ocamlfind -> Ocamlfind.conf_path ocamlfind)
-    | Hardcoded_path l -> List.map l ~f:Path.of_filename_relative_to_initial_cwd
-    | Opam2_environment opam_prefix ->
+    match (ocamlfind, query ~kind ~findlib_toolchain ~env) with
+    | ( Some ocamlfind
+      , ( Cross_compilation_using_findlib_toolchain _
+        | Opam2_environment _
+        | Unknown ) ) -> Ocamlfind.conf_path ocamlfind
+    | None, Cross_compilation_using_findlib_toolchain _toolchain ->
+      Code_error.raise
+        "Could not find ocamlfind in PATH or an environment variable \
+         OCAMLFIND_CONF"
+        [ ("context", Context_name.to_dyn context) ]
+    | _, Hardcoded_path l ->
+      List.map l ~f:Path.of_filename_relative_to_initial_cwd
+    | None, Opam2_environment opam_prefix ->
       let p = Path.of_filename_relative_to_initial_cwd opam_prefix in
       let p = Path.relative p "lib" in
       [ p ]
-    | Unknown -> (
-      match ocamlfind with
-      | None ->
-        (* TODO? *)
-        [ Path.relative (Path.parent_exn dir) "lib" ]
-      | Some ocamlfind -> Ocamlfind.conf_path ocamlfind)
+    | None, Unknown -> [ Path.relative (Path.parent_exn dir) "lib" ]
 end
 
 let check_fdo_support has_native ocfg ~name =
@@ -359,20 +356,14 @@ type instance =
 let create ~(kind : Kind.t) ~path ~env ~env_nodes ~name ~merlin ~targets
     ~host_context ~host_toolchain ~profile ~fdo_target_exe
     ~dynamically_linked_foreign_archives ~instrument_with =
-  let prog_not_found_in_path prog =
-    Utils.program_not_found prog ~context:name ~loc:None
-  in
   let which = Program.which ~path in
-
   let env_ocamlpath = Ocamlfind.ocamlpath env in
   let ocamlpath =
     let initial_ocamlpath = Ocamlfind.ocamlpath Env.initial in
     match (env_ocamlpath, initial_ocamlpath) with
     | [], [] -> []
     | _ :: _, [] -> env_ocamlpath
-    | [], _ :: _ ->
-      (* TODO? *)
-      initial_ocamlpath
+    | [], _ :: _ -> initial_ocamlpath
     | _, _ -> (
       match
         List.compare ~compare:Path.compare env_ocamlpath initial_ocamlpath
@@ -388,7 +379,6 @@ let create ~(kind : Kind.t) ~path ~env ~env_nodes ~name ~merlin ~targets
       | Default, None -> env_ocamlpath
       | _, _ -> ocamlpath
     in
-
     let* ocamlfind =
       Ocamlfind.discover_from_env ~env ~ocamlpath ~which >>| function
       | None -> None
@@ -400,17 +390,17 @@ let create ~(kind : Kind.t) ~path ~env ~env_nodes ~name ~merlin ~targets
             let toolchain = Context_name.to_string toolchain in
             Ocamlfind.set_toolchain ocamlfind ~toolchain)
     in
-
     let get_tool_using_findlib_config prog =
       Memo.Option.bind ocamlfind ~f:(Ocamlfind.tool ~prog)
     in
     let* ocamlc =
-      get_tool_using_findlib_config "ocamlc" >>= function
+      let ocamlc = "ocamlc" in
+      get_tool_using_findlib_config ocamlc >>= function
       | Some x -> Memo.return x
       | None -> (
-        which "ocamlc" >>| function
+        which ocamlc >>| function
         | Some x -> x
-        | None -> prog_not_found_in_path "ocamlc")
+        | None -> Utils.program_not_found ocamlc ~context:name ~loc:None)
     in
     let dir = Path.parent_exn ocamlc in
     let get_ocaml_tool prog =

src/dune_rules/findlib/findlib.ml

@@ -100,7 +100,7 @@ module Vars = struct
 
   let empty = String.Map.empty
 
-  let superpose = String.Map.superpose
+  let union = String.Map.union
 end
 
 module Config = struct
@@ -116,7 +116,6 @@ module Config = struct
       ; ("preds", Ps.to_dyn preds)
       ]
 
-
   let load config_file =
     let load p =
       let+ meta = Meta.load ~name:None p in
@@ -141,7 +140,12 @@ module Config = struct
                 let p = Path.Outside_build_dir.relative config_dir p in
                 load p)
           in
-          List.fold_left all_vars ~init:vars ~f:Vars.superpose
+          List.fold_left all_vars ~init:vars ~f:(fun acc vars ->
+              Vars.union acc vars ~f:(fun _ (x : Rules.t) y ->
+                  Some
+                    { Rules.set_rules = x.set_rules @ y.set_rules
+                    ; add_rules = x.add_rules @ y.add_rules
+                    }))
         | Error _ -> Memo.return vars)
       | Ok false | Error _ -> Memo.return vars
     in

test/blackbox-tests/test-cases/byte-code-only.t/run.t

@@ -1,3 +1,4 @@
+  $ export OCAMLFIND_CONF="/fake"
   $ env ORIG_PATH="$PATH" PATH="$PWD/ocaml-bin:$PATH" dune build @all --display short
         ocamlc bin/.toto.eobjs/byte/dune__exe__Toto.{cmi,cmo,cmt}
         ocamlc src/.foo.objs/byte/foo.{cmi,cmo,cmt}

test/blackbox-tests/test-cases/config/config-in-workspace-file.t

@@ -37,7 +37,7 @@ But is supported with Dune >= 3.0.0:
   > (display verbose)
   > EOF
   $ dune build -f 2>&1 | grep Hello | sed 's/&&.*echo/\&\& echo/'
-  Running[1]: (cd _build/default && echo 'Hello, world!')
+  Running[2]: (cd _build/default && echo 'Hello, world!')
   Hello, world!
 
 Make sure errors related to fields other than the ones allowed in the

test/blackbox-tests/test-cases/custom-cross-compilation/cross-compilation-ocamlfind.t

@@ -63,17 +63,24 @@ Dune should be able to find it too
 
   $ dune build --root=app @install -x foo
   Entering directory 'app'
-  File "dune", line 6, characters 12-18:
-  6 |  (libraries libdep))
-                  ^^^^^^
-  Error: Library "libdep" not found.
-  -> required by _build/default/.gen.eobjs/byte/dune__exe__Gen.cmi
-  -> required by _build/default/.gen.eobjs/native/dune__exe__Gen.cmx
-  -> required by _build/default/gen.exe
-  -> required by _build/default.foo/foo.ml
-  -> required by _build/install/default.foo/lib/repro/foo.ml
-  -> required by _build/default.foo/repro-foo.install
-  -> required by alias install (context default.foo)
   Leaving directory 'app'
-  [1]
 
+Library is built in the target context
+
+  $ ls app/_build/default.foo
+  META.repro
+  foo.ml
+  repro-foo.install
+  repro.a
+  repro.cma
+  repro.cmxa
+  repro.cmxs
+  repro.dune-package
+  repro.ml-gen
+
+Executable was built in the host context
+
+  $ ls app/_build/default
+  gen.exe
+  gen.ml
+  gen.mli

test/blackbox-tests/test-cases/trace-file.t/run.t

@@ -3,6 +3,7 @@
 This captures the commands that are being run:
 
   $ <trace.json grep '"X"' | cut -c 2- | sed -E 's/:[0-9]+/:.../g'
+  {"args":{"process_args":["printconf","conf"],"pid":...},"ph":"X","dur":...,"name":"ocamlfind","cat":"process","ts":...,"pid":...,"tid":...}
   {"args":{"process_args":["-config"],"pid":...},"ph":"X","dur":...,"name":"ocamlc.opt","cat":"process","ts":...,"pid":...,"tid":...}
   {"args":{"process_args":["-modules","-impl","prog.ml"],"pid":...},"ph":"X","dur":...,"name":"ocamldep.opt","cat":"process","ts":...,"pid":...,"tid":...}
   {"args":{"process_args":["-w","@[email protected]@30..39@[email protected]@[email protected]","-strict-sequence","-strict-formats","-short-paths","-keep-locs","-g","-bin-annot","-I",".prog.eobjs/byte","-no-alias-deps","-opaque","-o",".prog.eobjs/byte/prog.cmo","-c","-impl","prog.ml"],"pid":...},"ph":"X","dur":...,"name":"ocamlc.opt","cat":"process","ts":...,"pid":...,"tid":...}