merlin: introduce generate_merlin_rules

Signed-off-by: Javier Chávarri <[email protected]>
ocaml · Mar 28, 2024 · f5e5270 · f5e5270
1 parent a5e6f97
commit f5e5270
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Showing 4 changed files with 100 additions and 10 deletions.
diff --git a/src/dune_rules/context.ml b/src/dune_rules/context.ml
@@ -150,7 +150,10 @@ module Builder = struct
       extend_paths ~env paths
     in
     { t with
-      merlin
+      merlin =
+        (match merlin with
+         | Selected -> true
+         | Rules_only | Nothing -> false)
     ; profile
     ; dynamically_linked_foreign_archives
     ; instrument_with
@@ -610,7 +613,13 @@ module Group = struct
         | Opam opam -> Builder.set_workspace_base builder opam.base
         | Default default ->
           let builder = Builder.set_workspace_base builder default.base in
-          let merlin = workspace.merlin_context = Some (Workspace.Context.name context) in
+          let merlin =
+            workspace.merlin_context = Some (Workspace.Context.name context)
+            ||
+            match default.base.merlin with
+            | Rules_only -> true
+            | Nothing | Selected -> false
+          in
           { builder with merlin }
       in
       match context with

diff --git a/src/dune_rules/workspace.ml b/src/dune_rules/workspace.ml
@@ -266,6 +266,28 @@ module Context = struct
     ;;
   end
 
+  module Merlin = struct
+    type t =
+      | Selected
+      | Rules_only
+      | Nothing
+
+    let equal x y =
+      match x, y with
+      | Selected, Selected | Rules_only, Rules_only | Nothing, Nothing -> true
+      | Selected, (Rules_only | Nothing)
+      | (Rules_only | Nothing), Selected
+      | Rules_only, Nothing
+      | Nothing, Rules_only -> false
+    ;;
+
+    let to_dyn: t -> Dyn.t = function
+    | Selected -> String "selected"
+    | Rules_only -> String "rules_only"
+    | Nothing -> String "nothing"
+  ;;
+  end
+
   module Common = struct
     type t =
       { loc : Loc.t
@@ -279,7 +301,7 @@ module Context = struct
       ; fdo_target_exe : Path.t option
       ; dynamically_linked_foreign_archives : bool
       ; instrument_with : Lib_name.t list
-      ; merlin : bool
+      ; merlin : Merlin.t
       }
 
     let to_dyn { name; targets; host_context; _ } =
@@ -318,7 +340,7 @@ module Context = struct
            dynamically_linked_foreign_archives
            t.dynamically_linked_foreign_archives
       && List.equal Lib_name.equal instrument_with t.instrument_with
-      && Bool.equal merlin t.merlin
+      && Merlin.equal merlin t.merlin
     ;;
 
     let fdo_suffix t =
@@ -384,7 +406,8 @@ module Context = struct
           "instrument_with"
           (Dune_lang.Syntax.since syntax (2, 7) >>> repeat Lib_name.decode)
       and+ loc = loc
-      and+ merlin = field_b "merlin" in
+      and+ merlin = field_b "merlin"
+      and+ generate_merlin_rules = field_b "generate_merlin_rules" in
       fun ~profile_default ~instrument_with_default ->
         let profile = Option.value profile ~default:profile_default in
         let instrument_with =
@@ -409,7 +432,13 @@ module Context = struct
         ; fdo_target_exe
         ; dynamically_linked_foreign_archives
         ; instrument_with
-        ; merlin
+        ; merlin =
+            (match merlin with
+             | true -> Selected
+             | false ->
+               (match generate_merlin_rules with
+                | true -> Rules_only
+                | false -> Nothing))
         }
     ;;
   end
@@ -571,7 +600,7 @@ module Context = struct
           ; fdo_target_exe = None
           ; dynamically_linked_foreign_archives = true
           ; instrument_with = Option.value instrument_with ~default:[]
-          ; merlin = false
+          ; merlin = Nothing
           }
       }
   ;;
@@ -840,11 +869,11 @@ let step1 clflags =
                 !defined_names
                 (Context_name.Set.of_list (Context.all_names ctx));
            match Context.base ctx, acc with
-           | { merlin = true; _ }, Some _ ->
+           | { merlin = Selected; _ }, Some _ ->
              User_error.raise
                ~loc:(Context.loc ctx)
                [ Pp.text "you can only have one context for merlin" ]
-           | { merlin = true; _ }, None -> Some name
+           | { merlin = Selected; _ }, None -> Some name
            | _ -> acc)
        in
        let contexts =

diff --git a/src/dune_rules/workspace.mli b/src/dune_rules/workspace.mli
@@ -38,7 +38,18 @@ module Context : sig
     val equal : t -> t -> bool
   end
 
+  module Merlin : sig
+    type t =
+    | Selected
+    | Rules_only
+    | Nothing
+
+    val equal : t -> t -> bool
+
+    val to_dyn: t -> Dyn.t
+  end
   module Common : sig
+
     type t =
       { loc : Loc.t
       ; profile : Profile.t
@@ -57,7 +68,7 @@ module Context : sig
           the runtime system. *)
       ; dynamically_linked_foreign_archives : bool
       ; instrument_with : Lib_name.t list
-      ; merlin : bool
+      ; merlin : Merlin.t
       }
   end
 

diff --git a/test/blackbox-tests/test-cases/merlin/default-based-context.t/run.t b/test/blackbox-tests/test-cases/merlin/default-based-context.t/run.t
@@ -75,3 +75,44 @@ If Merlin field is present, this context is chosen
      -short-paths
      -keep-locs
      -g)))
+
+If `generate_merlin_rules` field is present, rules are generated even if merlin
+is disabled in that context
+
+  $ cat >dune-workspace <<EOF
+  > (lang dune 2.9)
+  > (context (default))
+  > (context
+  >  (default
+  >   (name cross)
+  >   (generate_merlin_rules)))
+  > EOF
+
+  $ dune build
+
+  $ ls -a _build/cross/.merlin-conf
+  .
+  ..
+  lib-foo
+
+  $ ls -a _build/default/.merlin-conf
+  .
+  ..
+  lib-foo
+
+  $ dune ocaml merlin dump-config "$PWD"
+  Foo: _build/default/foo
+  ((STDLIB OPAM_PREFIX)
+   (EXCLUDE_QUERY_DIR)
+   (B
+    $TESTCASE_ROOT/_build/default/.foo.objs/byte)
+   (S
+    $TESTCASE_ROOT)
+   (FLG
+    (-w
+     @1..3@5..28@30..39@43@46..47@49..57@61..62-40
+     -strict-sequence
+     -strict-formats
+     -short-paths
+     -keep-locs
+     -g)))