HCL2/NodeJS: fix proxy apply lowering for promises (#4317)

Applies cannot be proxied when the applied value is a promise.

Fixes #4315.

pkg/codegen/internal/test/testdata/aws-fargate.pp.ts

@@ -9,7 +9,7 @@ const subnets = vpc.then(vpc => aws.ec2.getSubnetIds({
 }));
 // Create a security group that permits HTTP ingress and unrestricted egress.
 const webSecurityGroup = new aws.ec2.SecurityGroup("webSecurityGroup", {
-    vpcId: vpc.id,
+    vpcId: vpc.then(vpc => vpc.id),
     egress: [{
         protocol: "-1",
         fromPort: 0,
@@ -43,14 +43,14 @@ const taskExecRolePolicyAttachment = new aws.iam.RolePolicyAttachment("taskExecR
 });
 // Create a load balancer to listen for HTTP traffic on port 80.
 const webLoadBalancer = new aws.elasticloadbalancingv2.LoadBalancer("webLoadBalancer", {
-    subnets: subnets.ids,
+    subnets: subnets.then(subnets => subnets.ids),
     securityGroups: [webSecurityGroup.id],
 });
 const webTargetGroup = new aws.elasticloadbalancingv2.TargetGroup("webTargetGroup", {
     port: 80,
     protocol: "HTTP",
     targetType: "ip",
-    vpcId: vpc.id,
+    vpcId: vpc.then(vpc => vpc.id),
 });
 const webListener = new aws.elasticloadbalancingv2.Listener("webListener", {
     loadBalancerArn: webLoadBalancer.arn,
@@ -85,7 +85,7 @@ const appService = new aws.ecs.Service("appService", {
     taskDefinition: appTask.arn,
     networkConfiguraiton: {
         assignPublicIp: true,
-        subnets: subnets.ids,
+        subnets: subnets.then(subnets => subnets.ids),
         securityGroups: [webSecurityGroup.id],
     },
     loadBalancers: [{

pkg/codegen/internal/test/testdata/aws-webserver.pp.ts

@@ -23,7 +23,7 @@ const server = new aws.ec2.Instance("server", {
     },
     instanceType: "t2.micro",
     securityGroups: [securityGroup.name],
-    ami: ami.id,
+    ami: ami.then(ami => ami.id),
     userData: `#!/bin/bash
 echo "Hello, World!" > index.html
 nohup python -m SimpleHTTPServer 80 &

pkg/codegen/nodejs/gen_program_expressions.go

@@ -132,18 +132,16 @@ func (g *generator) genApply(w io.Writer, expr *model.FunctionCallExpression) {
 
 	// If all of the arguments are promises, use promise methods. If any argument is an output, convert all other args
 	// to outputs and use output methods.
-	//
-	// TODO(pdg): unions
-	isPromise := make([]bool, len(applyArgs))
-	allPromises := true
+	isOutput := make([]bool, len(applyArgs))
+	anyOutputs := false
 	for i, arg := range applyArgs {
-		_, isPromise[i] = arg.Type().(*model.PromiseType)
-		allPromises = allPromises && isPromise[i]
+		isOutput[i] = isOutputType(arg.Type())
+		anyOutputs = anyOutputs || isOutput[i]
 	}
 
-	apply, all := "apply", "pulumi.all"
-	if allPromises {
-		apply, all = "then", "Promise.all"
+	apply, all := "then", "Promise.all"
+	if anyOutputs {
+		apply, all = "apply", "pulumi.all"
 	}
 
 	if len(applyArgs) == 1 {
@@ -156,7 +154,7 @@ func (g *generator) genApply(w io.Writer, expr *model.FunctionCallExpression) {
 			if i > 0 {
 				g.Fgen(w, ", ")
 			}
-			if isPromise[i] {
+			if anyOutputs && !isOutput[i] {
 				g.Fgenf(w, "pulumi.output(%v)", o)
 			} else {
 				g.Fgenf(w, "%v", o)

pkg/codegen/nodejs/gen_program_lower.go

@@ -9,12 +9,27 @@ import (
 	"github.com/pulumi/pulumi/sdk/go/common/util/contract"
 )
 
+func isOutputType(t model.Type) bool {
+	switch t := t.(type) {
+	case *model.OutputType:
+		return true
+	case *model.UnionType:
+		for _, t := range t.ElementTypes {
+			if _, isOutput := t.(*model.OutputType); isOutput {
+				return true
+			}
+		}
+	}
+	return false
+}
+
 // canLiftScopeTraversalExpression returns true if this variable access expression can be lifted. Any variable access
 // expression that does not contain references to potentially-undefined values (e.g. optional fields of a resource) can
 // be lifted.
 func (g *generator) canLiftScopeTraversalExpression(v *model.ScopeTraversalExpression) bool {
 	for _, p := range v.Parts {
-		if model.IsOptionalType(model.GetTraversableType(p)) {
+		t := model.GetTraversableType(p)
+		if model.IsOptionalType(t) || !isOutputType(t) {
 			return false
 		}
 	}