diff --git a/test/blackbox-tests/test-cases/dune-init/public-sublibrary.t b/test/blackbox-tests/test-cases/dune-init/public-sublibrary.t
new file mode 100644
index 000000000000..9507ea99da0d
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+++ b/test/blackbox-tests/test-cases/dune-init/public-sublibrary.t
@@ -0,0 +1,10 @@
+Sub-library names should be accepted:
+
+  $ dune init lib lib_s1_s2 --public lib.sub1.sub2
+  dune: option '--public': invalid component name `lib.sub1.sub2'
+        Library names must be non-empty and composed only of the
+        following
+        characters: 'A'..'Z', 'a'..'z', '_' or '0'..'9'.
+  Usage: dune init library [OPTION]… NAME [PATH]
+  Try 'dune init library --help' or 'dune --help' for more information.
+  [1]