Run ocamlformat from build context root

This will output errors relative to the correct directory.

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>

CHANGES.md

@@ -80,8 +80,6 @@ unreleased
 - Run `ocamlformat` relative to the context root. This improves the locations of
   errors. (#..., fixes #1370, @rgrinberg)
 
-- Support the `.cc` extension fro C++ sources (#2195, fixes #83, @rgrinberg)
-
 1.9.3 (06/05/2019)
 ------------------
 

src/format_rules.ml

@@ -38,19 +38,15 @@ let gen_rules_output sctx (config : Dune_file.Auto_format.t) ~output_dir =
   let resolve_program =
     Super_context.resolve_program ~dir sctx ~loc:(Some loc) in
   let ocamlformat_deps = lazy (
-    depend_on_files ~named:[".ocamlformat"; ".ocamlformat-ignore"] (Path.source source_dir)
+    depend_on_files ~named:[".ocamlformat"; ".ocamlformat-ignore"]
+      (Path.source source_dir)
   ) in
   let setup_formatting file =
     let open Build.O in
     let input_basename = Path.Source.basename file in
     let input = Path.relative dir input_basename in
     let output = Path.relative output_dir input_basename in
 
-    let run_build_root =
-      let dir = Super_context.build_dir sctx in
-      Build.run ~dir
-    in
-
     let ocaml kind =
       if Dune_file.Auto_format.includes config Ocaml then
         let exe = resolve_program "ocamlformat" in
@@ -64,7 +60,8 @@ let gen_rules_output sctx (config : Dune_file.Auto_format.t) ~output_dir =
           ; Target output
           ]
         in
-        Some (Lazy.force ocamlformat_deps >>> Build.run ~dir:(Super_context.build_dir sctx) exe args)
+        Some (Lazy.force ocamlformat_deps
+              >>> Build.run ~dir:(Super_context.build_dir sctx) exe args)
       else
         None
     in