Allow destination and config-file in aliases

We only loaded the configuration once, which meant that aliases always
used the initial configuration file and destination.

We don't want to load the configuration in subcommands as it is not
passed all the options we need. But just checking if we are in a
subcommand is enough - the alias reloads and the subcommand does not.

One thing to note is that anything passed on the command line overrides
what is in the alias, so if an alias says
`other_config: config -c config/deploy2.yml` and you run
`kamal other_config -c config/deploy.yml`, it won't switch.

test/cli/main_test.rb

@@ -460,6 +460,7 @@ class CliMainTest < CliTestCase
 
   test "run an alias for a console" do
     run_command("console", config_file: "deploy_with_aliases").tap do |output|
+      assert_no_match "App Host: 1.1.1.4", output
       assert_match "docker exec app-console-999 bin/console on 1.1.1.5", output
       assert_match "App Host: 1.1.1.5", output
     end
@@ -486,6 +487,33 @@ class CliMainTest < CliTestCase
     end
   end
 
+  test "switch config file with an alias" do
+    with_config_files do
+      with_argv([ "other_config" ]) do
+        stdouted { Kamal::Cli::Main.start }.tap do |output|
+          assert_match ":service_with_version: app2-999", output
+        end
+      end
+    end
+  end
+
+  test "switch destination with an alias" do
+    with_config_files do
+      with_argv([ "other_destination_config" ]) do
+        stdouted { Kamal::Cli::Main.start }.tap do |output|
+          assert_match ":service_with_version: app3-999", output
+        end
+      end
+    end
+  end
+
+  test "run on primary via alias" do
+    run_command("primary_details", config_file: "deploy_with_aliases").tap do |output|
+      assert_match "App Host: 1.1.1.1", output
+      assert_no_match "App Host: 1.1.1.2", output
+    end
+  end
+
   test "upgrade" do
     invoke_options = { "config_file" => "test/fixtures/deploy_with_accessories.yml", "skip_hooks" => false, "confirmed" => true, "rolling" => false }
     Kamal::Cli::Main.any_instance.expects(:invoke).with("kamal:cli:proxy:upgrade", [], invoke_options)
@@ -530,6 +558,20 @@ class CliMainTest < CliTestCase
       end
     end
 
+    def with_config_files
+      Dir.mktmpdir do |tmpdir|
+        config_dir = File.join(tmpdir, "config")
+        FileUtils.mkdir_p(config_dir)
+        FileUtils.cp "test/fixtures/deploy.yml", config_dir
+        FileUtils.cp "test/fixtures/deploy2.yml", config_dir
+        FileUtils.cp "test/fixtures/deploy.elsewhere.yml", config_dir
+
+        Dir.chdir(tmpdir) do
+          yield
+        end
+      end
+    end
+
     def assert_file(file, content)
       assert_match content, File.read(file)
     end