.NET Core precedence of configuration files by item or by section?

Question

I have appsettings.json and environment specific settings like appsettings.development.json for my .NET application. Does the latter override the former at the item level or at the section level?

Suppose that appsettings.json has

"Foo": {
  "Setting1": "aaa",
  "Setting2": "bbb"
  }

and that appsettings.Development.json has

"Foo": {
  "Setting1": "zzz"
}

When I'm executing my application in my development environment, what will be returned by Configuration.GetSection("Foo").GetValue("Setting2")?

• Does the entire Foo section in appsettings.Development.json override the entire Foo section in appsettings.json, so that Foo.Setting2 in my application will be undefined?
• Or does only Foo.Setting1 get replaced, so that Foo.Setting2 in my application will still return "bbb"?

Answer 1

That was one of those questions that I realized ten minutes later was easy enough to test in the setup I already have. The overrides are per-setting, not per-section. The value of Foo.Setting2 = "bbb" would from appsettings.json would pass through to the app. Well, here it is for reference for anyone else with the same question.