How to inject globals without affecting client code.

SomeClass-bad.cs

class SomeClass{
  private int someValue;

  public SomeClass( int someValue ){
    this.someValue = someValue;
  }

  public int SomeFunction(){
    return someValue + GlobalReference.someFunction();
  }
}
  

SomeClass-good.cs

class SomeClass{
  private int someValue;
  private Global myReference;

  public SomeClass( int someValue ) :
    this( GlobalReference, someValue )
  { }

  public SomeClass( Global global, int someValue ){
    this.myReference = global;
    this.someValue = someValue;
  }

  public void SomeFunction(){
    return someValue + myReference.someFunction();
  }
}