Enable l1-stack-refernce test (#686)

This required two fixes. One to handle `getOutput` functions in PCL and
rewrite them into variable expressions. e.g. `getOutput(res, "key")`
gets rewritten to `${res.outputs["key"]}`.

Secondly resources in the "pulumi" package, like stack reference
resources, don't need a "pulumi" plugin so don't return that in
GetRequiredPlugins.

.changes/unreleased/Improvements-686.yaml

@@ -0,0 +1,6 @@
+component: codegen
+kind: Improvements
+body: Support stack references in program generation
+time: 2024-11-15T17:19:10.259289815Z
+custom:
+  PR: "686"

cmd/pulumi-language-yaml/language_test.go

@@ -172,7 +172,6 @@ func runTestingHost(t *testing.T) (string, testingrpc.LanguageTestClient) {
 
 // Add test names here that are expected to fail and the reason why they are failing
 var expectedFailures = map[string]string{
-	"l1-stack-reference":                    "YAML does not support fn::getOutput",
 	"l2-invoke-options":                     "cannot assign expression",
 	"l2-provider-grpc-config-schema-secret": "Detected a secret leak in state",
 	"l2-parameterized-resource":             "could not load schema for subpackage, provider not known",

cmd/pulumi-language-yaml/testdata/projects/l1-stack-reference/Main.yaml

@@ -0,0 +1,8 @@
+resources:
+  ref:
+    type: pulumi:pulumi:StackReference
+    properties:
+      name: organization/other/dev
+outputs:
+  plain: ${ref.outputs["plain"]}
+  secret: ${ref.outputs["secret"]}

cmd/pulumi-language-yaml/testdata/projects/l1-stack-reference/Pulumi.yaml

@@ -0,0 +1,2 @@
+name: l1-stack-reference
+runtime: yaml

pkg/pulumiyaml/codegen/gen_program.go

@@ -737,6 +737,20 @@ func (g *generator) function(f *model.FunctionCallExpression) syn.Node {
 		return wrapFn("readFile", g.expr(f.Args[0]))
 	case "secret":
 		return wrapFn("secret", g.expr(f.Args[0]))
+	case "getOutput":
+		// getOutput(var, key) => ${var.outputs[key]}
+
+		root := g.expr(f.Args[0]).String() // This will be something like ${var}
+		// Strip the ${} from the root as we're going to rewrap it
+		root = root[2 : len(root)-1]
+
+		key := g.expr(f.Args[1])
+		// We need to wrap the key in quotes if its a string, but not if its a number
+		if _, ok := key.(*syn.StringNode); ok {
+			key = syn.String(fmt.Sprintf("%q", key.String()))
+		}
+
+		return syn.String(fmt.Sprintf("${%s.outputs[%s]}", root, key))
 	case pcl.IntrinsicConvert:
 		// We can't perform the convert, but it might happen automatically.
 		// This works for enums, as well as number -> strings.

pkg/pulumiyaml/packages.go

@@ -148,6 +148,11 @@ func GetReferencedPlugins(tmpl *ast.TemplateDecl) ([]Plugin, syntax.Diagnostics)
 
 	acceptType := func(r *Runner, typeName string, version, pluginDownloadURL *ast.StringExpr) {
 		pkg := ResolvePkgName(typeName)
+		// skip the "pulumi" package
+		if pkg == "pulumi" {
+			return
+		}
+
 		if entry, found := pluginMap[pkg]; found {
 			if v := version.GetValue(); v != "" && entry.version != v {
 				if entry.version == "" {