Hello friends. I have a method that creates records in custom metadata. It works as expected but now I am having a hard time figuring out how to get test coverage for it. 

Initially got an error on the line that enques the deployment via Metadata.Operations.enqueueDeployment which said that metadata cannot be deployed in a test context.

Then I found the suggestion of just skipping that line with a ternary operator, which is the version I have posted here. And that gives me 'Fake Job Id' is not a proper id. Strange that this seems to have worked for other people on that stackexchange post. 

At this point I need to seek some advice from those of you that are more experienced. Thanks!!

@future
    public static void createCustomMetaData(string acctName, string acctId) {

    string fullname = 'Product_Selection_Search_Parameter.'+acctName.replace(' ','_');    
    // Set up custom metadata to be created in the subscriber org. thanks to https://www.sfdcpanther.com/create-update-custom-metadata-using-apex/
    Metadata.CustomMetadata customMetadata =  new Metadata.CustomMetadata();
    customMetadata.fullName = fullname;
    customMetadata.label = acctName;

    Metadata.CustomMetadataValue typeField = new Metadata.CustomMetadataValue();
    typeField.field = 'Type__c';
    typeField.value = 'Top-Up';
	Metadata.CustomMetadataValue acctField = new Metadata.CustomMetadataValue();
    acctField.field = 'Value__c';
    acctField.value = acctId;

    customMetadata.values.add(typeField);
	customMetadata.values.add(acctField);

    Metadata.DeployContainer mdContainer = new Metadata.DeployContainer();
    mdContainer.addMetadata(customMetadata);

    // Setup deploy callback, MyDeployCallback implements
    // the Metadata.DeployCallback interface 
    CustomMetadataCallback callback = new CustomMetadataCallback();

    // Enqueue custom metadata deployment
    // jobId is the deployment ID
    Id jobId = Test.isRunningTest() ? 'Fake Job Id' : Metadata.Operations.enqueueDeployment(mdContainer, callback);
    }

@isTest
public with sharing class di_PartnerCreation_Test {
    
    @TestSetup
    static void makeData(){
        TestData_Research_Director director = new TestData_Research_Director();
        director.Construct_Account(new TestData_Research(), true);
        director.Construct_NonStandardPBE(new TestData_Research(), true);
    }

    public static testMethod void testDIPartnerCreationMethods_Act() {
        Account act = [select Id, Name from Account limit 1];
        PriceBook2 pb = [select Id from PriceBook2 where IsStandard = false];

        map<string, string> pbTest = di_PartnerCreation_lcController.getPriceBookOptions(act, 'AUD');
        boolean exProds = di_PartnerCreation_lcController.hasExistingProducts(act.Id);
        di_PartnerCreation_lcController.createProducts(act, 'AUD');
        di_PartnerCreation_lcController.createPriceBookEntries(act, 'AUD', pb.Id);
    }

    public static testMethod void testDIPartnerCreationMethods_NoAct() {

        map<string, string> currencyMap = di_PartnerCreation_lcController.getCurrencies();

    }
}