MONGOID-5599 Test on multiple mongoses

.evergreen/config.yml

@@ -427,7 +427,6 @@ axes:
         display_name: Sharded Cluster
         variables:
            TOPOLOGY: "sharded-cluster"
-           SINGLE_MONGOS: true
 
   - id: "auth"
     display_name: Authentication

.evergreen/config/axes.yml.erb

@@ -54,7 +54,6 @@ axes:
         display_name: Sharded Cluster
         variables:
            TOPOLOGY: "sharded-cluster"
-           SINGLE_MONGOS: true
 
   - id: "auth"
     display_name: Authentication

.evergreen/run-tests.sh

@@ -93,7 +93,12 @@ fi
 
 export BUNDLE_GEMFILE
 
-export MONGODB_URI="mongodb://localhost:27017/?appName=test-suite&$uri_options"
+if test "$TOPOLOGY" = "sharded-cluster"; then
+  # We assume that sharded cluster has two mongoses
+  export MONGODB_URI="mongodb://localhost:27017,localhost:27018/?appName=test-suite&$uri_options"
+else
+  export MONGODB_URI="mongodb://localhost:27017/?appName=test-suite&$uri_options"
+fi
 
 set +e
 if test -n "$TEST_CMD"; then

spec/integration/shardable_spec.rb

@@ -6,6 +6,7 @@
 
 describe 'Sharding helpers' do
   require_topology :sharded
+  min_server_version '4.4'
 
   describe 'shard_collection rake task' do
     let(:shard_collections) do

spec/support/expectations.rb

@@ -3,7 +3,6 @@
 
 module Mongoid
   module Expectations
-
     def connection_class
       if defined?(Mongo::Server::ConnectionBase)
         Mongo::Server::ConnectionBase
@@ -14,6 +13,9 @@ def connection_class
     end
 
     def expect_query(number)
+      if %i[ sharded load-balanced ].include?(ClusterConfig.instance.topology) && number > 0
+        skip 'This spec requires replica set or standalone topology'
+      end
       rv = nil
       RSpec::Mocks.with_temporary_scope do
         if number > 0