Rename Woodchipper-related stuff.

No functional changes introduced by this commit.

Renamed:

    woodchipper.js -> constants.js
    Woodchipper -> ConstantVisitor
    debranch -> propagate

bin/jsx

@@ -3,7 +3,7 @@
 
 var visitors = require('../vendor/fbtransform/visitors').transformVisitors;
 var transform = require('../vendor/fbtransform/lib/transform').transform;
-var debranch = require("../vendor/woodchipper").debranch;
+var propagate = require("../vendor/constants").propagate;
 
 require("commoner").resolve(function(id) {
   var context = this;
@@ -32,10 +32,9 @@ require("commoner").resolve(function(id) {
   return context.makePromise(function(callback) {
     var constants = context.config.constants || {};
 
-    // Debranching means removing any obviously dead code after
-    // replacing constant conditional expressions with literal
-    // (boolean) values.
-    debranch(constants, source, function(source) {
+    // Constant propagation means removing dead code after replacing
+    // constant conditional expressions with literal (boolean) values.
+    propagate(constants, source, function(source) {
       callback(null, source);
     });
   });

vendor/woodchipper.js → vendor/constants.js

@@ -17,17 +17,17 @@
 
 var recast = require('recast');
 
-exports.debranch = function(constants, source, writeback) {
+exports.propagate = function(constants, source, writeback) {
   recast.runString(
     source,
     function(ast, callback) {
-      callback(new Woodchipper(constants).visit(ast));
+      callback(new ConstantVisitor(constants).visit(ast));
     },
     { writeback: writeback }
   );
 };
 
-var Woodchipper = recast.Visitor.extend({
+var ConstantVisitor = recast.Visitor.extend({
   init: function(constants) {
     this.constants = constants || {};
   },
@@ -57,6 +57,6 @@ var Woodchipper = recast.Visitor.extend({
 if (!module.parent) {
   var constants = JSON.parse(process.argv[3]);
   recast.run(function(ast, callback) {
-    callback(new Woodchipper(constants).visit(ast));
+    callback(new ConstantVisitor(constants).visit(ast));
   });
 }