Run CI on Windows (#156)

* CI: run on Windows

* runs-on: ${{ matrix.setup.os }}

* Try tests on Windows in bash shell

* Use single-line shell-agnostic commands

* windows: don't runtest, just build

---------

Co-authored-by: Antonio Nuno Monteiro <[email protected]>

.github/workflows/build.yml

@@ -13,41 +13,39 @@ concurrency:
 
 jobs:
   build:
-    runs-on: ubuntu-latest
+    runs-on: ${{ matrix.setup.os }}
     strategy:
       matrix:
         setup:
-          - {ocaml-version: '4.05', runtest: false}
-          - {ocaml-version: '4.09', runtest: true}
-          - {ocaml-version: '4.14', runtest: true}
-          - {ocaml-version: '5.1', runtest: true}
-          - {ocaml-version: '5.2', runtest: true}
+          - {ocaml-version: '4.05', os: ubuntu-latest, runtest: false}
+          - {ocaml-version: '4.09', os: ubuntu-latest, runtest: true}
+          - {ocaml-version: '4.14', os: ubuntu-latest, runtest: true}
+          - {ocaml-version: '5.1', os: ubuntu-latest, runtest: true}
+          - {ocaml-version: '5.2', os: ubuntu-latest, runtest: true}
+          - {ocaml-version: '5.2', os: windows-latest, runtest: false}
     steps:
     - uses: actions/checkout@v4
     - uses: ocaml/setup-ocaml@v3
       with:
         ocaml-compiler:  ${{ matrix.setup.ocaml-version }}
     - name: Setup opam
       run: opam pin add -n .
-    - name: Install dependencies
-      run: opam depext -yt mad
     - name: Build
       if: ${{ ! matrix.setup.runtest }}
       run: opam install .
-    - name: Build and test
+    - name: Build for testing
+      if: ${{ matrix.setup.runtest }}
+      run: opam install -t .
+    - name: Test
       if: ${{ matrix.setup.runtest }}
-      run: |
-        opam install -t .
-        eval $(opam env)
-        dune build @github_action_tests
+      run: opam exec -- dune build @github_action_tests
 
   nix-build:
     runs-on: ${{ matrix.setup.os }}
     strategy:
       matrix:
         setup:
           - {ocamlVersion: 4_12, os: ubuntu-latest}
-          - {ocamlVersion: 4_13, os: ubuntu-latest}
           - {ocamlVersion: 4_14, os: ubuntu-latest}
           - {ocamlVersion: 5_1, os: ubuntu-latest}
           - {ocamlVersion: 5_2, os: ubuntu-latest}