ParseTree version 2.0.0 has been released!

ParseTree is a C extension (using RubyInline) that extracts the parse
tree for an entire class or a specific method and returns it as a
s-expression (aka sexp) using ruby's arrays, strings, symbols, and
integers.

As an example:

def conditional1(arg1)
if arg1 == 0 then
return 1
end
return 0
end

becomes:

[:defn,
:conditional1,
[:scope,
[:block,
[:args, :arg1],
[:if,
[:call, [:lvar, :arg1], :==, [:array, [:lit, 0]]],
[:return, [:lit, 1]],
nil],
[:return, [:lit, 0]]]]]

* Uses RubyInline, so it just drops in.
* Includes SexpProcessor and CompositeSexpProcessor.
* Allows you to write very clean filters.
* Includes UnifiedRuby, allowing you to automatically rewrite ruby quirks.
* ParseTree#parse_tree_for_string lets you parse arbitrary strings of ruby.
* Includes parse_tree_show, which lets you quickly snoop code.
* echo "1+1" | parse_tree_show -f for quick snippet output.
* Includes parse_tree_abc, which lets you get abc metrics on code.
* abc metrics = numbers of assignments, branches, and calls.
* whitespace independent metric for method complexity.
* Includes parse_tree_deps, which shows you basic class level dependencies.
* Does not work on the core classes, as they are not ruby (yet).

Changes:

* 2 major enhancements:

* Rewrite methods completely rewritten. Rewriters:
* are no longer recursive.
* are no longer required to empty the sexp coming in.
* are depth first, so rewriter gets passed everything already normalized.
* keep rewriting until type doesn't change.
* are magical goodness.
* Added UnifiedRuby module to aid others in writing clean SexpProcessors:
* bmethod/dmethod/fbody unified with defn
* fcall/vcall unified with call
* resbody unified with itself (lots of different forms)

* 5 minor enhancements:

* Add #modules to Module.
* Add Sexp::for shortcut for Sexp.from_array ParseTree.translate(...).
* Add parens for :block nodes as appropriate. May be overzealous.
* Made add_to_parse_tree global for reuse by other C extensions.
* Made test_ruby2ruby MUCH more rigorous with circular testing.

* 6 bug fixes:

* Added $TESTING = true to pt_testcase.rb. OOPS!
* Fixed some circular bugs, mostly by hacking them out, wrt operator precidence.
* Fixed splat arg processing when arg has no name.
* Fixed trinary operator.
* Fixed BMETHOD with no arguments.
* Removed hacky "self." thing for defs at top level PT use.