Lambda transform hangs indefinitely

[Swisk]

Describe what happened

when trying to run a transform to modify a lambda created elsewhere to work within a VPC, pulumi hangs indefinitely.

To note, it works when using transformations instead of transforms, so this leads one to conclude there is something specific about how transforms is implemented that causes the difference.

Sample program

assuming lambda created elsewhere in some component

export class Lambda extends pulumi.ComponentResource {
  constructor(
    name: string,
    args: LambdaModuleArgs,
    opts?: pulumi.ComponentResourceOptions,
  ) {
     ....const lambdaFunction = new aws.lambda.Function(
      ...
}

const myLambda = new Lambda(
      `${name}`,
      {
        args: value
      },
      {
        parent: this,
        transforms: [addVpcConfigToLambda],
      },
    );

where the transform logic looks like this:

const addVpcConfigToLambda: pulumi.ResourceTransform = (
      args: ResourceTransformArgs,
    ): ResourceTransformResult | undefined => {
      if (args.type === "aws:lambda/function:Function") {

        const vpcConfig: aws.types.input.lambda.FunctionVpcConfig = {
          subnetIds: mySubnetIds,
          securityGroupIds: [mySecurityGroup.id],
        };

        const updatedProps = { ...args.props, vpcConfig: vpcConfig };

        // Return the modified properties and original options
        return { props: updatedProps, opts: args.opts };
      }

      return { props: args.props, opts: args.opts };
    };

Log output

No response

Affected Resource(s)

No response

Output of pulumi about

CLI
Version 3.160.0
Go Version go1.24.1
Go Compiler gc

Plugins
KIND NAME VERSION
resource aws 6.69.0
resource aws 6.45.0
resource aws-native 1.25.0
resource aws-native 0.110.0
resource aws-native 0.110.0
resource aws-native 0.110.0
resource aws-native 0.110.0
resource aws-native 0.110.0
resource aws-native 0.110.0
resource aws-native 0.110.0
resource awsx 2.13.0
resource cloudflare 5.33.1
resource command 1.0.2
resource datadog 4.28.1
resource docker 4.6.1
resource docker 3.6.1
language nodejs 3.160.0-dev.0
resource random 4.16.8
resource time 0.0.17
resource tls 5.0.10

Host
OS darwin
Version 15.4
Arch arm64

Additional context

No response

Contributing

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[corymhall]

@Swisk thanks for reporting this issue. Can you provide us a program that we can use to reproduce the issue? Thanks!