ci: speed up Test workflow

.github/workflows/test.yml

@@ -13,16 +13,19 @@ jobs:
         os: [ubuntu-latest, macos-latest, windows-latest]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - uses: actions/setup-go@v5
         with:
           go-version: stable
           cache-dependency-path: go.sum
       - uses: julia-actions/setup-julia@v2
-      - uses: julia-actions/cache@v2
+      - uses: julia-actions/cache@v3
       - uses: r-lib/actions/setup-r@v2
-        with:
-          rtools-version: none
+        if: runner.os != 'Windows'
+      # windows-latest ships R; setup-r would reinstall it plus Ghostscript (~30s).
+      - if: runner.os == 'Windows'
+        shell: bash
+        run: cygpath -w "$(ls -d /c/Program\ Files/R/R-*/bin | tail -1)" >> "$GITHUB_PATH"
       - run: julia -e 'using Pkg; Pkg.add("Revise")'
       - shell: bash
         run: go test -C go -v -coverprofile=coverage.out -covermode=atomic

go/julia_integration_test.go

@@ -50,6 +50,7 @@ type streamChunk struct {
 }
 
 func TestJuliaWarmSession(t *testing.T) {
+	t.Parallel()
 	socketPath := sharedDaemon(t)
 	cwd := sharedJuliaCwd(t)
 
@@ -321,6 +322,7 @@ func TestClientDisconnectInterruptsEval(t *testing.T) {
 }
 
 func TestRevisePicksUpPackageChanges(t *testing.T) {
+	t.Parallel()
 	socketPath := sharedDaemon(t)
 
 	pkgDir := sessionCwd(t)
@@ -360,6 +362,7 @@ func TestRevisePicksUpPackageChanges(t *testing.T) {
 // frame; showing a result whose method was just defined (an @enum's namemap) must not
 // throw "method too new". Guards the Base.invokelatest wrap in runtime.jl.
 func TestJuliaWorldAgeDisplay(t *testing.T) {
+	t.Parallel()
 	socketPath := sharedDaemon(t)
 
 	pkgDir := sessionCwd(t)
@@ -380,6 +383,7 @@ func TestJuliaWorldAgeDisplay(t *testing.T) {
 // hooks (flush buffers, finalizers) rather than SIGKILL the process. The hook
 // writes a marker file; its presence proves the process exited cleanly.
 func TestKillRunsAtexitHooks(t *testing.T) {
+	t.Parallel()
 	cwd, err := os.Getwd()
 	require.NoError(t, err)
 	sess := newSession("julia", newSentinel(), nil, nil)