benchmark: review comments

- Make multiple runs of benchmark actually run.
- Fix non-existent driver-benchmarks.json by adopting a simpler
  approach: instead of outputing in a file, then promoting, then running
  `cat`, we just output in the standard output.

Signed-off-by: Paul-Elliot <[email protected]>

Makefile

@@ -13,14 +13,9 @@ publish-docs:
 test :
 	dune runtest
 
-# Echo is disabled as the benchmarks results are printed on stdout.
-# '@bench' exit status is not checked as it's very likely to fail due to
-# needing promotion rather than because it really failed.
 .PHONY : bench
 bench:
-	-@dune build @bench
-	@dune promote driver-benchmarks.json
-	@cat driver-benchmarks.json
+	@dune build @bench
 
 .PHONY : coverage
 coverage :

doc/dune

@@ -31,15 +31,12 @@
   (> %{ocaml_version} 4.11))
  (deps
   (package odoc)
+  (universe) ; Benchmark depends on the running programs in the background
   (glob_files *.mld)
   (glob_files library_mlds/*)
   (glob_files examples/*.ml*))
  (action
-  (progn
-   ; Make sure the benchmark result is created as Dune would not show the diff
-   ; if the script failed before creating it.
-   (write-file driver-benchmarks.json "")
-   (run ocaml-mdx-test --force-output %{dep:driver.mld}))))
+   (run ocaml-mdx-test --force-output %{dep:driver.mld})))
 
 (rule
  (alias docgen)

dune

@@ -12,4 +12,4 @@
 (rule
  (alias bench)
  (action
-  (diff driver-benchmarks.json doc/driver-benchmarks.json)))
+  (cat doc/driver-benchmarks.json)))