2GP dependent managed package creation failing with null explanation message

Question

I have an sfdx-project.json of this form that worked about week ago to create an unpublished version of a package that depends on another package:

{
    "packageDirectories": [
        {
            ...
            "dependencies": [
                {
                    "package": "[email protected]"
                }
            ]
        }
    ],
    ...
    "packageAliases": {
        "[email protected]": "04t***************"
    }
}

but today (26 Jan 2022) the sfdx:force:package:version:create fails repeatedly this error:

ERROR running force:package:version:create:  Multiple errors occurred:
(1) An error occurred while trying to install a package dependency,
    ID 04t************: null
(2) An error occurred while trying to install a package dependency,
    ID 04t************: null

Changing the dependency to an earlier version generates the corresponding error for that. I've updated to the latest CLI from 7.133.0-cddd46d to 7.134.0-4f69b20.

Anyone else experiencing this or have a solution? I note that I'm also getting this new message from SFDX:

Warning: Based on feedback from Salesforce Partners, we’re enhancing the package ancestry feature. Starting in Spring ‘22, the ancestor version field is required when you create a package version. Look for more details, including how to override the ancestry requirement, in the packaging section of the Spring ‘22 Salesforce Release Notes and in the Salesforce DX Developer Guide.

Answer 1

As usual, the cause is "operator error". I was missing:

--definitionfile config/project-scratch-def.json

from my sfdx:force:package:version:create and so was not turning on the features in the packaging org that the depended on package needs. Hence its installation was failing, albeit with just null output as the reason message rather than something more helpful.