From f0e17fc20fc2bf5603eb930ae1704f06a21ecce4 Mon Sep 17 00:00:00 2001
From: Jeremy Ashkenas <jashkenas@gmail.com>
Date: Tue, 10 Apr 2012 17:07:38 -0400
Subject: [PATCH] fixing compound assignments to global variables. oof.

---
 lib/coffee-script/nodes.js | 2 +-
 src/nodes.coffee           | 3 ++-
 test/assignment.coffee     | 7 +++++++
 3 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/lib/coffee-script/nodes.js b/lib/coffee-script/nodes.js
index 88ea7982..40204246 100644
--- a/lib/coffee-script/nodes.js
+++ b/lib/coffee-script/nodes.js
@@ -1631,7 +1631,7 @@
     Assign.prototype.compileConditional = function(o) {
       var left, right, _ref2;
       _ref2 = this.variable.cacheReference(o), left = _ref2[0], right = _ref2[1];
-      if (left.base instanceof Literal && left.base.value !== "this" && !o.scope.check(left.base.value)) {
+      if (!left.properties.length && left.base instanceof Literal && left.base.value !== "this" && !o.scope.check(left.base.value)) {
         throw new Error("the variable \"" + left.base.value + "\" can't be assigned with " + this.context + " because it has not been defined.");
       }
       if (__indexOf.call(this.context, "?") >= 0) {
diff --git a/src/nodes.coffee b/src/nodes.coffee
index ec683d44..c30db3d4 100644
--- a/src/nodes.coffee
+++ b/src/nodes.coffee
@@ -1119,7 +1119,8 @@ exports.Assign = class Assign extends Base
   compileConditional: (o) ->
     [left, right] = @variable.cacheReference o
     # Disallow conditional assignment of undefined variables.
-    if left.base instanceof Literal and left.base.value != "this" and not o.scope.check left.base.value
+    if not left.properties.length and left.base instanceof Literal and 
+           left.base.value != "this" and not o.scope.check left.base.value
       throw new Error "the variable \"#{left.base.value}\" can't be assigned with #{@context} because it has not been defined."
     if "?" in @context then o.isExistentialEquals = true
     new Op(@context[...-1], left, new Assign(right, @value, '=') ).compile o
diff --git a/test/assignment.coffee b/test/assignment.coffee
index dd4bbb0c..8426dc21 100644
--- a/test/assignment.coffee
+++ b/test/assignment.coffee
@@ -296,6 +296,13 @@ test "#1627: prohibit conditional assignment of undefined variables", ->
   
   throws (-> CoffeeScript.compile "-> -> -> x ?= 10"), null, "prohibit (-> -> -> x ?= 10)"
   doesNotThrow (-> CoffeeScript.compile "x = null; -> -> -> x ?= 10"), "allow (x = null; -> -> -> x ?= 10)"
+  
+test "more existential assignment", ->
+  global.temp ?= 0
+  eq global.temp, 0
+  global.temp or= 100
+  eq global.temp, 100
+  delete global.temp
 
 test "#1348, #1216: existential assignment compilation", ->
   nonce = {}