Schemes: target/build type map doesn't seem to support non-array strings

[chucker]

I had a scheme like so:

schemes:
  MyApp:
    build:
      targets:
        MyApp: all
        MyAppTests: test

However, the generated Xcode project showed it (in Xcode) with all build types enabled for both targets.

The docs seem to say this syntax should work: targets: [String:String] or [String:[String]]. (I'm assuming the above code is the first of those syntaxes.)

However, I had to change the YAML to be an array for Xcode to do the right thing:

schemes:
  MyApp:
    build:
      targets:
        MyApp: all
        MyAppTests: [test]