Add Slurm Docker tests

Start on #105, alternative to #125

Uses container from https://github.com/giovtorres/docker-centos7-slurm

.github/workflows/UnitTests.jl

@@ -0,0 +1,44 @@
+name: Unit Tests
+
+on:
+  pull_request:
+
+  push:
+    branches:
+      - master
+
+jobs:
+  test-slurm:
+    timeout-minutes: 20
+    strategy:
+      matrix:
+        os: [ubuntu-latest]
+        julia_version: ["1.5", "nightly"]
+        julia_arch: [x64]
+      fail-fast: false
+
+    runs-on: ${{ matrix.os }}
+
+    env:
+      SLURM: "latest"
+
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v2.2.0
+
+    - uses: julia-actions/setup-julia@latest
+      with:
+        arch: ${{ matrix.julia_arch }}
+        version: ${{ matrix.julia_version }}
+
+    - name: Start Slurm Docker image
+      run: |
+        docker pull giovtorres/docker-centos7-slurm:$SLURM
+        docker run -d -it -h ernie -v $(pwd):/SlurmTools -v $(julia -e 'print(dirname(Sys.BINDIR))'):/julia --name slurm-$SLURM giovtorres/docker-centos7-slurm:$SLURM
+
+    - name: Instantiate package
+      run: docker exec slurm-$SLURM /julia/bin/julia --project=/SlurmTools -e 'using Pkg; Pkg.instantiate(verbose=true); Pkg.build(verbose=true)'
+
+    - name: Run tests
+      run: docker exec slurm-$SLURM /julia/bin/julia --project=/SlurmTools -e 'using Pkg; Pkg.test(test_args=["slurm"])'
+

test/runtests.jl

@@ -18,6 +18,18 @@ using Distributed
     wait(rmprocs(workers()))
 end
 
+if "slurm" in ARGS
+    @testset "Slurm" begin
+        p = addprocs_slurm(1)
+        @test nprocs() == 2
+        @test workers() == p
+        @test fetch(@spawnat :any myid()) == p[1]
+        @test remotecall_fetch(+,p[1],1,1) == 2
+        rmprocs(p)
+        @test nprocs() == 1
+        @test workers() == [1]
+    end
+end
 
 @static if Sys.iswindows()
     windows_which(command) = `powershell.exe -Command Get-Command $command`