Can't add resources to a list when there are wildcards in ignoreChanges

[lichtie]

Describe what happened

As of version 4.14.0, the vSphere provider no longer lets you add new items to a list (e.g. a disk to a VirtualMachine) when ignoreChanges is used with a wildcard on that list. The operation fails with the error:

cannot ignore changes to the following properties because one or more elements of the path are missing.

Sample program

const vm = new vsphere.VirtualMachine(
  "testVM",
  {
    name: "testVM",
    resourcePoolId: resourcePoolId,
    datastoreId: datastoreId,
    folder: folder,
    numCpus: numCPUs,
    memory: memoryMB,
    guestId: "otherGuest",
    networkInterfaces: [
      {
        networkId: networkId,
        adapterType: "vmxnet3",
      },
    ],
    disks: diskSizesGB.map((size, index) => ({
      label: `disk${index + 1}`,
      size: size,
      eagerlyScrub: false,
      thinProvisioned: true,
      unitNumber: index,
      datastoreId: "datastoreId",
    })),
    clone: {
      templateUuid: "templateUuid",
    },
  },
  { ignoreChanges: ["disks[*].datastoreId"] }
);

Log output

No response

Affected Resource(s)

No response

Output of pulumi about

CLI          
Version      3.178.0
Go Version   go1.24.4
Go Compiler  gc

Plugins
KIND      NAME           VERSION
resource  gcp            8.36.0
language  nodejs         3.178.0
resource  synced-folder  0.0.9
resource  vsphere        4.14.0

Host     
OS       darwin
Version  15.5
Arch     arm64

This project is written in nodejs: executable='/opt/homebrew/bin/node' version='v24.1.0'

Current Stack: ElisabethLich/repro-vsphere/dev

Found no resources associated with dev

Found no pending operations associated with dev

Backend        
Name           pulumi.com
URL            https://app.pulumi.com/ElisabethLich
User           ElisabethLich
Organizations  ElisabethLich, team-ce, demo
Token type     personal

Dependencies:
NAME                   VERSION
@pulumi/gcp            8.36.0
@pulumi/pulumi         3.181.0
@pulumi/synced-folder  0.0.9
@pulumi/vsphere        4.14.0
@types/node            18.19.115
typescript             5.8.3

Additional context

No response

Contributing

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[VenelinMartinov]

@lichtie did this work in 4.13? If not, which is the last working version?

[VenelinMartinov]

The user reported that the a ignoreChanges worked in 4.9.1 and was likely broken by 4.11.2

We've shipped quite a few changes in the bridge in that period, notably the PlanResourceChange refactor. Seems likely that something there has regressed the ignoreChanges behaviour.

We'll need to sort out test account credentials in order to reproduce the issue and root-cause it.

Blocked on #540

[t0yv0]

Source of the error message.

[t0yv0]

I have a little bit of a synthetic repro in pulumi/pulumi-terraform-bridge#3139 which reproduces this error message. Still some work to narrow down the root cause here.

[corymhall]

@lichtie it looks like for array properties Pulumi does not allow you to add or remove from the array if ignoreChanges uses a wildcard. This makes sense because there is no way for Pulumi to know which item in the array is new.

Without being able to test with this specific provider, i've testing with different providers and looking at the Pulumi core code I would be surprised if this worked on any version of the vsphere provider while using the latest version of the Pulumi CLI. My hunch is that this may have worked on an older version of the Pulumi CLI (pre 3.73.0).

It would be great if there was a better error message though and we need to update the documentation for ignoreChanges to note this.