6.0.0

I'm extremely stupid and didn't commit as I go. To anyone reading this
I'm extremely sorry. A lot of these changes are very broad and I plan on
releasing Babel 6.0.0 today live on stage at Ember Camp London so I'm
afraid I couldn't wait. If you're ever in London I'll buy you a beer
(or assorted beverage!) to make up for it, also I'll kiss your feet and
give you a back massage, maybe.

packages/babel-helper-explode-assignable-expression/README.md

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+# babel-helper-explode-assignable-expression
+
+## Usage
+
+TODO

packages/babel-helper-explode-assignable-expression/package.json

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+{
+  "name": "babel-helper-explode-assignable-expression",
+  "version": "1.0.0",
+  "description": "",
+  "repository": "babel/babel",
+  "license": "MIT",
+  "main": "lib/index.js",
+  "dependencies": {
+    "babel-traverse": "^5.8.20",
+    "babel-runtime": "^5.8.20",
+    "babel-types": "^5.8.20"
+  }
+}

packages/babel-helper-explode-assignable-expression/src/index.js

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+/* @flow */
+
+import type { Scope } from "babel-traverse";
+import * as t from "babel-types";
+
+function getObjRef(node, nodes, file, scope) {
+  let ref;
+  if (t.isIdentifier(node)) {
+    if (scope.hasBinding(node.name)) {
+      // this variable is declared in scope so we can be 100% sure
+      // that evaluating it multiple times wont trigger a getter
+      // or something else
+      return node;
+    } else {
+      // could possibly trigger a getter so we need to only evaluate
+      // it once
+      ref = node;
+    }
+  } else if (t.isMemberExpression(node)) {
+    ref = node.object;
+
+    if (t.isIdentifier(ref) && scope.hasBinding(ref.name)) {
+      // the object reference that we need to save is locally declared
+      // so as per the previous comment we can be 100% sure evaluating
+      // it multiple times will be safe
+      return ref;
+    }
+  } else {
+    throw new Error(`We can't explode this node type ${node.type}`);
+  }
+
+  let temp = scope.generateUidIdentifierBasedOnNode(ref);
+  nodes.push(t.variableDeclaration("var", [
+    t.variableDeclarator(temp, ref)
+  ]));
+  return temp;
+}
+
+function getPropRef(node, nodes, file, scope) {
+  let prop = node.property;
+  let key = t.toComputedKey(node, prop);
+  if (t.isLiteral(key)) return key;
+
+  let temp = scope.generateUidIdentifierBasedOnNode(prop);
+  nodes.push(t.variableDeclaration("var", [
+    t.variableDeclarator(temp, prop)
+  ]));
+  return temp;
+}
+
+export default function (
+  node: Object,
+  nodes: Array<Object>,
+  file,
+  scope: Scope,
+  allowedSingleIdent?: boolean,
+): {
+  uid: Object;
+  ref: Object;
+} {
+  let obj;
+  if (t.isIdentifier(node) && allowedSingleIdent) {
+    obj = node;
+  } else {
+    obj = getObjRef(node, nodes, file, scope);
+  }
+
+  let ref, uid;
+
+  if (t.isIdentifier(node)) {
+    ref = node;
+    uid = obj;
+  } else {
+    let prop = getPropRef(node, nodes, file, scope);
+    let computed = node.computed || t.isLiteral(prop);
+    uid = ref = t.memberExpression(obj, prop, computed);
+  }
+
+  return {
+    uid: uid,
+    ref: ref
+  };
+}