Tests: add an example using dune site and build info

compiler/tests-build-info/dune

@@ -0,0 +1,22 @@
+
+(env
+ (_
+  (js_of_ocaml
+   (compilation_mode separate))))
+
+(executable
+ (name main)
+ (modes js byte native)
+ (modules main mysites)
+ (libraries dune-build-info dune-site))
+
+(generate_sites_module
+ (module mysites)
+ (sites js_of_ocaml-tests))
+
+(install
+ (section libexec)
+ (package js_of_ocaml-tests)
+ (files
+   (main.bc.js as test-build-info.bc.js)
+   (main.exe as test-build-info.exe)))

compiler/tests-build-info/dune-project

@@ -0,0 +1,6 @@
+(lang dune 3.7)
+(using dune_site 0.1)
+
+(package
+ (name js_of_ocaml-tests)
+ (sites (share tests)))

compiler/tests-build-info/main.ml

@@ -0,0 +1,18 @@
+let version =
+  match Build_info.V1.version () with
+  | None -> "unknown"
+  | Some v -> Build_info.V1.Version.to_string v
+
+let () =
+  print_endline "Version:";
+  match String.split_on_char '-' version with
+  | [ tag; plus; _commit; dirty ] ->
+      Printf.printf "%s-%s-%s-%s\n%!" tag plus "xxxxx" dirty
+  | [ tag; plus; _commit ] ->
+     Printf.printf "%s-%s-%s\n%!" tag plus "xxxxx"
+  | [ x ] -> print_endline x
+  | _ -> Printf.printf "unexpected: %s\n%!" version
+
+let () =
+  print_endline "Sites:";
+  List.iter print_endline Mysites.Sites.tests