Make an error with dune_lang >= 2.0

ocaml · Sep 20, 2019 · 0354e88 · 0354e88
1 parent e5fd864
commit 0354e88
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Showing 3 changed files with 16 additions and 5 deletions.
diff --git a/src/dune/preprocessing.ml b/src/dune/preprocessing.ml
@@ -581,12 +581,13 @@ let make sctx ~dir ~expander ~dep_kind ~lint ~preprocess ~preprocessor_deps
   in
   let preprocessor_deps =
     let loc, deps = preprocessor_deps in
-    if (not (is_preprocessing preprocess)) && not (List.is_empty deps) then
-      User_warning.emit ~loc
+    ( if (not (is_preprocessing preprocess)) && not (List.is_empty deps) then
+      let is_error = Dune_project.dune_version (Scope.project scope) >= (2, 0) in
+      User_warning.emit ~loc ~is_error
         [ Pp.text
             "This preprocessor_deps field will be ignored because no \
              preprocessor is configured."
-        ];
+        ] );
     SC.Deps.interpret sctx deps ~expander |> Build.memoize "preprocessor deps"
   in
   let lint_module =

diff --git a/test/blackbox-tests/test-cases/unused-preprocessor-deps/dune-project b/test/blackbox-tests/test-cases/unused-preprocessor-deps/dune-project
diff --git a/test/blackbox-tests/test-cases/unused-preprocessor-deps/run.t b/test/blackbox-tests/test-cases/unused-preprocessor-deps/run.t
@@ -2,6 +2,9 @@
 Should warn.
 
   $ touch a.ml b.ml
+
+  $ echo "(lang dune 1.11)" > dune-project
+  $ echo "(allow_approximate_merlin)" >> dune-project
   $ dune build
   File "dune", line 5, characters 1-39:
   5 |  (preprocessor_deps does-not-exist.txt))
@@ -13,3 +16,12 @@ Should warn.
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   Warning: This preprocessor_deps field will be ignored because no preprocessor
   is configured.
+
+  $ echo "(lang dune 2.0)" > dune-project
+  $ dune build
+  File "dune", line 5, characters 1-39:
+  5 |  (preprocessor_deps does-not-exist.txt))
+       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+  Error: This preprocessor_deps field will be ignored because no preprocessor
+  is configured.
+  [1]