DX-format projects cannot deploy a single Custom Field to a metadata-format org

[Chuck Liddell]

Trying to deploy a single custom field to a sandbox that is linked to a DX-format project does not just deploy the field itself, but also the entire object and all related entities (fields, list views, etc).

IC successfully generates a temporary package.xml file that looks correct:

<?xml version="1.0" encoding="UTF-8"?>
<Package xmlns="http://soap.sforce.com/2006/04/metadata">
    <types>
        <members>Account.My_Custom_Field__c</members>
        <name>CustomField</name>
    </types>
    <version>48.0</version>
</Package>

And runs this commands:

sfdx force:source:deploy -u <mySandbox> -o -g -x <pathToTempPackageFile> -w 0 --json

However, the CLI seems to be ignoring this simple manifest and instead packaging the entire object’s local folder.

 INFO - r.ForceComSfdxMetadataDeployer - Deployment status = SUCCEEDED
DEBUG - r.ForceComSfdxMetadataDeployer - Processing 133 component successes.

‌

[Scott Wells]

Issue tracker grooming. If this is still an issue, please feel free to reopen, ideally with a concrete reproduction scenario.