Fix conditioning of tests.

  - Use build_if instead of enabled_if to condition on build deps.
  - Add test dependency on OCAML_MARIADB_* environment variables.
  - Only run tests if OCAML_MARIADB_DB is set and restore @runtest in
    the opam package.

Author: paurkedal

mariadb.opam

@@ -13,7 +13,7 @@ build: [
   ["dune" "subst"] {dev}
   ["dune" "build" "-p" name "-j" jobs
     "@install"
-    "@default" {with-test} # but not @runtest since it would require a MariaDB server
+    "@runtest" {with-test}
     "@doc" {with-doc}
   ]
 ]

tests/README.md

@@ -9,12 +9,16 @@ latter there are instances depending on the concurrency library:
 | nonblocking-async   | Tests the nonblocking API using async.
 | nonblocking-lwt     | Tests the nonblocking API using Lwt.
 
-Tests require access to a MariaDB instance to run.  You will likely need to
-set some environment variables to point the test suite to the right place:
+Tests require access to a MariaDB or MySQL database, which must be declared
+by setting the following environment variables:
 
 | Environment variable | Description
 | -------------------- | -----------
-| `OCAML_MARIADB_HOST` | Host to connect to.
+| `OCAML_MARIADB_HOST` | Host name or IP address to connect to.
+| `OCAML_MARIADB_PORT` | Port number to connect to.
 | `OCAML_MARIADB_USER` | Authenticate as the given user.
 | `OCAML_MARIADB_PASS` | Authenticate with the given password.
 | `OCAML_MARIADB_DB`   | Connect to the given database.
+
+These tests will only run if `OCAML_MARIADB_DB` has been set, but the
+executable will still be built.  The remaining variables are optional.

tests/blocking/dune

@@ -1,3 +1,10 @@
 (test
  (name blocking_testsuite)
+ (enabled_if (<> %{env:OCAML_MARIADB_DB=__none__} __none__))
+ (deps
+  (env_var OCAML_MARIADB_HOST)
+  (env_var OCAML_MARIADB_PORT)
+  (env_var OCAML_MARIADB_USER)
+  (env_var OCAML_MARIADB_PASS)
+  (env_var OCAML_MARIADB_DB))
  (libraries mariadb nonblocking_testsuite unix))

tests/nonblocking-async/dune

@@ -1,4 +1,11 @@
 (test
  (name nonblocking_testsuite_async)
- (libraries mariadb async nonblocking_testsuite)
- (enabled_if %{lib-available:lwt}))
+ (build_if %{lib-available:lwt})
+ (enabled_if (<> %{env:OCAML_MARIADB_DB=__none__} __none__))
+ (deps
+  (env_var OCAML_MARIADB_HOST)
+  (env_var OCAML_MARIADB_PORT)
+  (env_var OCAML_MARIADB_USER)
+  (env_var OCAML_MARIADB_PASS)
+  (env_var OCAML_MARIADB_DB))
+ (libraries mariadb async nonblocking_testsuite))

tests/nonblocking-lwt/dune

@@ -1,4 +1,11 @@
 (test
  (name nonblocking_testsuite_lwt)
- (libraries mariadb lwt lwt.unix nonblocking_testsuite)
- (enabled_if %{lib-available:lwt}))
+ (build_if %{lib-available:lwt})
+ (enabled_if (<> %{env:OCAML_MARIADB_DB=__none__} __none__))
+ (deps
+  (env_var OCAML_MARIADB_HOST)
+  (env_var OCAML_MARIADB_PORT)
+  (env_var OCAML_MARIADB_USER)
+  (env_var OCAML_MARIADB_PASS)
+  (env_var OCAML_MARIADB_DB))
+ (libraries mariadb lwt lwt.unix nonblocking_testsuite))