go program gen: prompt array conversion, unused range vars, id handling (#4884)

CHANGELOG.md

@@ -3,6 +3,9 @@ CHANGELOG
 
 ## HEAD (Unreleased)
 
+- Go program gen: prompt array conversion, unused range vars, id handling
+  [#4884](https://github.com/pulumi/pulumi/pull/4884)
+
 - Go program gen handling for prompt optional primitives
   [#4875](https://github.com/pulumi/pulumi/pull/4875)
 

pkg/codegen/go/gen_program.go

@@ -29,6 +29,7 @@ type generator struct {
 	splatSpiller        *splatSpiller
 	optionalSpiller     *optionalSpiller
 	scopeTraversalRoots codegen.StringSet
+	arrayHelpers        map[string]*promptToInputArrayHelper
 }
 
 func GenerateProgram(program *hcl2.Program) (map[string][]byte, hcl.Diagnostics, error) {
@@ -50,6 +51,7 @@ func GenerateProgram(program *hcl2.Program) (map[string][]byte, hcl.Diagnostics,
 		splatSpiller:        &splatSpiller{},
 		optionalSpiller:     &optionalSpiller{},
 		scopeTraversalRoots: codegen.NewStringSet(),
+		arrayHelpers:        make(map[string]*promptToInputArrayHelper),
 	}
 
 	g.Formatter = format.NewFormatter(g)
@@ -212,6 +214,14 @@ func (g *generator) genPostamble(w io.Writer, nodes []hcl2.Node) {
 	g.Fprint(w, "return nil\n")
 	g.Fprintf(w, "})\n")
 	g.Fprintf(w, "}\n")
+
+	g.genHelpers(w)
+}
+
+func (g *generator) genHelpers(w io.Writer) {
+	for _, v := range g.arrayHelpers {
+		v.generateHelperMethod(w)
+	}
 }
 
 func (g *generator) genNode(w io.Writer, n hcl2.Node) {
@@ -243,7 +253,7 @@ func (g *generator) genResource(w io.Writer, r *hcl2.Resource) {
 		g.genTemps(w, temps)
 	}
 
-	instantiate := func(varName, resourceName string) {
+	instantiate := func(varName, resourceName string, w io.Writer) {
 		if g.scopeTraversalRoots.Has(varName) || strings.HasPrefix(varName, "_") {
 			g.Fgenf(w, "%s, err := %s.New%s(ctx, %s, ", varName, mod, typ, resourceName)
 		} else {
@@ -273,13 +283,24 @@ func (g *generator) genResource(w io.Writer, r *hcl2.Resource) {
 
 		g.Fgenf(w, "var %s []*%s.%s\n", resName, mod, typ)
 
-		g.Fgenf(w, "for key0, val0 := range %.v {\n", rangeExpr)
-		instantiate("_res", fmt.Sprintf(`fmt.Sprintf("%s-%%v", key0)`, resName))
+		// ahead of range statement declaration generate the resource instantiation
+		// to detect and removed unused k,v variables
+		var buf bytes.Buffer
+		instantiate("_res", fmt.Sprintf(`fmt.Sprintf("%s-%%v", key0)`, resName), &buf)
+		instantiation := buf.String()
+		isValUsed := strings.Contains(instantiation, "val0")
+		valVar := "_"
+		if isValUsed {
+			valVar = "val0"
+		}
+
+		g.Fgenf(w, "for key0, %s := range %.v {\n", valVar, rangeExpr)
+		g.Fgen(w, instantiation)
 		g.Fgenf(w, "%s = append(%s, _res)\n", resName, resName)
 		g.Fgenf(w, "}\n")
 
 	} else {
-		instantiate(resName, fmt.Sprintf("\"%s\"", resName))
+		instantiate(resName, fmt.Sprintf("%q", resName), w)
 	}
 
 }
@@ -357,7 +378,11 @@ func (g *generator) genTempsMultiReturn(w io.Writer, temps []interface{}, zeroVa
 			g.Fgenf(w, "}\n")
 		case *splatTemp:
 			argTyp := g.argumentTypeName(t.Value.Each, t.Value.Each.Type(), false)
-			g.Fgenf(w, "var %s []%s\n", t.Name, argTyp)
+			if strings.Contains(argTyp, ".") {
+				g.Fgenf(w, "var %s %sArray\n", t.Name, argTyp)
+			} else {
+				g.Fgenf(w, "var %s []%s\n", t.Name, argTyp)
+			}
 			g.Fgenf(w, "for _, val0 := range %.v {\n", t.Value.Source)
 			g.Fgenf(w, "%s = append(%s, %.v)\n", t.Name, t.Name, t.Value.Each)
 			g.Fgenf(w, "}\n")

pkg/codegen/go/gen_program_expressions.go

@@ -436,7 +436,24 @@ func (g *generator) genScopeTraversalExpression(w io.Writer, expr *model.ScopeTr
 
 	// TODO if it's an array type, we need a lowering step to turn []string -> pulumi.StringArray
 	if isInput {
-		g.Fgenf(w, "%s(", g.argumentTypeName(expr, expr.Type(), isInput))
+		argType := g.argumentTypeName(expr, expr.Type(), isInput)
+		if strings.HasSuffix(argType, "Array") {
+			// use a helper to transform prompt arrays into inputty arrays
+			var helper *promptToInputArrayHelper
+			if h, ok := g.arrayHelpers[argType]; ok {
+				helper = h
+			} else {
+				// helpers are emitted at the end in the postamble step
+				helper = &promptToInputArrayHelper{
+					destType: argType,
+				}
+				g.arrayHelpers[argType] = helper
+			}
+			g.Fgenf(w, "%s(", helper.getFnName())
+		} else {
+			g.Fgenf(w, "%s(", g.argumentTypeName(expr, expr.Type(), isInput))
+		}
+
 	}
 
 	// TODO: this isn't exhaustively correct as "range" could be a legit var name

pkg/codegen/go/gen_program_test.go

@@ -119,6 +119,7 @@ func newTestGenerator(t *testing.T, testFile string) *generator {
 			splatSpiller:        &splatSpiller{},
 			optionalSpiller:     &optionalSpiller{},
 			scopeTraversalRoots: codegen.NewStringSet(),
+			arrayHelpers:        make(map[string]*promptToInputArrayHelper),
 		}
 		g.Formatter = format.NewFormatter(g)
 		return g

pkg/codegen/go/gen_program_utils.go

@@ -0,0 +1,56 @@
+package gen
+
+import (
+	"fmt"
+	"io"
+	"strings"
+
+	"github.com/pulumi/pulumi/sdk/v2/go/common/util/contract"
+)
+
+type promptToInputArrayHelper struct {
+	destType string
+}
+
+var primitives = map[string]string{
+	"String":  "string",
+	"Bool":    "bool",
+	"Int":     "int",
+	"Int64":   "int64",
+	"Float64": "float64",
+}
+
+func (p *promptToInputArrayHelper) generateHelperMethod(w io.Writer) {
+	promptType := p.getPromptItemType()
+	inputType := p.getInputItemType()
+	fnName := p.getFnName()
+	fmt.Fprintf(w, "func %s(arr []%s) %s {\n", fnName, promptType, p.destType)
+	fmt.Fprintf(w, "var pulumiArr %s\n", p.destType)
+	fmt.Fprintf(w, "for _, v := range arr {\n")
+	fmt.Fprintf(w, "pulumiArr = append(pulumiArr, %s(v))\n", inputType)
+	fmt.Fprintf(w, "}\n")
+	fmt.Fprintf(w, "return pulumiArr\n")
+	fmt.Fprintf(w, "}\n")
+}
+
+func (p *promptToInputArrayHelper) getFnName() string {
+	parts := strings.Split(p.destType, ".")
+	contract.Assertf(len(parts) == 2, "promptToInputArrayHelper destType expected to have two parts.")
+	return fmt.Sprintf("to%s%s", Title(parts[0]), Title(parts[1]))
+}
+
+func (p *promptToInputArrayHelper) getPromptItemType() string {
+	inputType := p.getInputItemType()
+	parts := strings.Split(inputType, ".")
+	contract.Assertf(len(parts) == 2, "promptToInputArrayHelper destType expected to have two parts.")
+	typ := parts[1]
+	if t, ok := primitives[typ]; ok {
+		return t
+	}
+
+	return typ
+}
+
+func (p *promptToInputArrayHelper) getInputItemType() string {
+	return strings.TrimSuffix(p.destType, "Array")
+}

pkg/codegen/internal/test/testdata/aws-eks.pp.go

@@ -71,7 +71,7 @@ func main() {
 			vpcSubnet = append(vpcSubnet, _res)
 		}
 		var rta []*ec2.RouteTableAssociation
-		for key0, val0 := range zones.Names {
+		for key0, _ := range zones.Names {
 			_res, err := ec2.NewRouteTableAssociation(ctx, fmt.Sprintf("rta-%v", key0), &ec2.RouteTableAssociationArgs{
 				RouteTableId: eksRouteTable.ID(),
 				SubnetId:     vpcSubnet[key0].ID(),
@@ -81,7 +81,7 @@ func main() {
 			}
 			rta = append(rta, _res)
 		}
-		var splat0 []pulumi.String
+		var splat0 pulumi.StringArray
 		for _, val0 := range vpcSubnet {
 			splat0 = append(splat0, val0.ID())
 		}

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

@@ -86,7 +86,7 @@ func main() {
 			return err
 		}
 		webLoadBalancer, err := elasticloadbalancingv2.NewLoadBalancer(ctx, "webLoadBalancer", &elasticloadbalancingv2.LoadBalancerArgs{
-			Subnets: pulumi.StringArray(subnets.Ids),
+			Subnets: toPulumiStringArray(subnets.Ids),
 			SecurityGroups: pulumi.StringArray{
 				webSecurityGroup.ID(),
 			},
@@ -154,7 +154,7 @@ func main() {
 			TaskDefinition: appTask.Arn,
 			NetworkConfiguration: &ecs.ServiceNetworkConfigurationArgs{
 				AssignPublicIp: pulumi.Bool(true),
-				Subnets:        pulumi.StringArray(subnets.Ids),
+				Subnets:        toPulumiStringArray(subnets.Ids),
 				SecurityGroups: pulumi.StringArray{
 					webSecurityGroup.ID(),
 				},
@@ -174,3 +174,10 @@ func main() {
 		return nil
 	})
 }
+func toPulumiStringArray(arr []string) pulumi.StringArray {
+	var pulumiArr pulumi.StringArray
+	for _, v := range arr {
+		pulumiArr = append(pulumiArr, pulumi.String(v))
+	}
+	return pulumiArr
+}