Mocking

Mocking provides a way to substitute records from a Database with some prepared data. Data can be prepared in form of SObject records and lists in Apex code or Static Resource .csv file. Mocked queries won't make any SOQL's and simply return data set in method definition, mock will ignore all filters and relations, what is returned depends solely on data provided to the method. Mocking is working only during test execution. To mock SOQL query, use .mockId(id) method to make it identifiable. If you mark more than one query with the same ID, all marked queries will return the same data.

public with sharing class ExampleController {

    public static List<Account> getPartnerAccounts(String accountName) {
        return SOQL_Account.query()
            .with(Account.BillingCity, Account.BillingCountry)
            .whereAre(SOQL.FilterGroup
                .add(SOQL.Filter.name().contains(accountName))
                .add(SOQL.Filter.recordType().equal('Partner'))
            )
            .mockId('ExampleController.getPartnerAccounts')
            .toList();
    }
}

Then in test simply pass data you want to get from Selector to SOQL.setMock(id, data) method. Acceptable formats are: List<SObject> or SObject. Then during execution Selector will return desired data.

List of records

@IsTest
private class ExampleControllerTest {

    @IsTest
    static void getPartnerAccounts() {
        List<Account> accounts = new List<Account>{
            new Account(Name = 'MyAccount 1'),
            new Account(Name = 'MyAccount 2')
        };

        SOQL.setMock('ExampleController.getPartnerAccounts', accounts);

        // Test
        List<Account> result = ExampleController.getPartnerAccounts('MyAccount');

        Assert.areEqual(accounts, result);
    }
}

Single record

@IsTest
private class ExampleControllerTest {

    @IsTest
    static void getPartnerAccount() {
        SOQL.setMock('ExampleController.getPartnerAccount', new Account(Name = 'MyAccount 1'));

        // Test
        Account result = (Account) ExampleController.getPartnerAccounts('MyAccount');

        Assert.areEqual('MyAccount 1', result.Name);
    }
}

Static resource

@IsTest
private class ExampleControllerTest {

    @IsTest
    static void getPartnerAccounts() {
        SOQL.setMock('ExampleController.getPartnerAccounts', Test.loadData(Account.SObjectType, 'ProjectAccounts'));

        // Test
        List<Account> result = ExampleController.getPartnerAccounts('MyAccount');

        Assert.areEqual(5, result.size());
    }
}

Count Result

@IsTest
private class ExampleControllerTest {

    @IsTest
    static void getPartnerAccountsCount() {
        SOQL.setCountMock('mockingQuery', 2);

        Integer result = SOQL.of(Account.sObjectType).count().mockId('mockingQuery').toInteger();

        Assert.areEqual(2, result);
    }
}