Pretty printer spacing between decls is inconsistent

[joscoh]

I am constructing a module via the Dafny AST C# AST, then printing it using PrintTopLevelDecls. I have a ModuleDefinition, and its TopLevelDecls are, in order, two (or more) AliasModuleDecls, and a DefaultClassDecl with the rest of the module code. The resulting pretty-printed Dafny looks like this:

module A {

  import B = ...

  import C = ...
  function foo() ...
}

Ie, there are newlines between each of the module imports, but no newline between the last module import and the default class. Within the class, each of the declared functions have a newline between them. So before the default class is the only place at which a newline is not printed between subsequent declarations.