Test Closure Compiler behavior with different extern fomats

[jmmk]

Looking at the externs contained in https://github.com/google/closure-compiler/tree/master/contrib/externs, it seems like only the top-level namespace and the prototypes are defined. Is it actually necessary to recurse into everything?

e.g.

var namespace = {
    property: {
        anotherProperty: 1234
    }
};

If we use namespace.property.anotherProperty inside a program, do we need to provide externs for namespace.property.anotherProperty, or does namespace.property suffice?

[jmmk]

https://github.com/google/closure-compiler/blob/master/contrib/externs/maps/google_maps_api_v3.js also includes enum properties. Is this necessary or is it an optimization? If an optimization, what does it do/allow?

[jmmk]

Ideas for how to test this issue (#22) and others related to Closure Compiler behavior (#10, #9, #1):

• Make requests to the Closure Compiler Service API and inspect the output

[jmmk]

Things to test:

• Are nested properties necessary
• Do we need to define the prototype, or can we just specify properties of an object
• Do we even have to make the distinction between a function and an object

[jmmk]

Probably easier to run on the command line: closure-compiler --compilation_level ADVANCED [--externs externs.js,] --js file.js[,] [--js_output_file output.js]