merging #1353

lib/nodes.js

@@ -1271,7 +1271,10 @@
     Assign.prototype.compileConditional = function(o) {
       var left, rite, _ref2;
       _ref2 = this.variable.cacheReference(o), left = _ref2[0], rite = _ref2[1];
-      return new Op(this.context.slice(0, -1), left, new Assign(rite, this.value, '='), void 0, __indexOf.call(this.context, "?") >= 0).compile(o);
+      if (__indexOf.call(this.context, "?") >= 0) {
+        o.isExistentialEquals = true;
+      }
+      return new Op(this.context.slice(0, -1), left, new Assign(rite, this.value, '=')).compile(o);
     };
     Assign.prototype.compileSplice = function(o) {
       var code, exclusive, from, fromDecl, fromRef, name, to, valDef, valRef, _ref2, _ref3, _ref4;
@@ -1569,9 +1572,8 @@
   exports.Op = Op = (function() {
     var CONVERSIONS, INVERSIONS;
     __extends(Op, Base);
-    function Op(op, first, second, flip, isExistentialEquals) {
+    function Op(op, first, second, flip) {
       var call;
-      this.isExistentialEquals = isExistentialEquals;
       if (op === 'in') {
         return new In(first, second);
       }
@@ -1688,15 +1690,9 @@
         fst = this.first;
         ref = fst;
       }
-      if (this.isExistentialEquals) {
-        return new If(new Existence(fst).invert(), this.second, {
-          type: 'if'
-        }).addElse(fst).compile(o);
-      } else {
-        return new If(new Existence(fst), ref, {
-          type: 'if'
-        }).addElse(this.second).compile(o);
-      }
+      return new If(new Existence(fst), ref, {
+        type: 'if'
+      }).addElse(this.second).compile(o);
     };
     Op.prototype.compileUnary = function(o) {
       var op, parts;
@@ -2158,8 +2154,14 @@
       }
     };
     If.prototype.compileStatement = function(o) {
-      var body, child, cond, ifPart;
+      var body, child, cond, exeq, ifPart;
       child = del(o, 'chainChild');
+      exeq = del(o, 'isExistentialEquals');
+      if (exeq) {
+        return new If(this.condition.invert(), this.elseBodyNode(), {
+          type: 'if'
+        }).compile(o);
+      }
       cond = this.condition.compile(o, LEVEL_PAREN);
       o.indent += TAB;
       body = this.ensureBlock(this.body).compile(o);

src/nodes.coffee

@@ -1020,7 +1020,8 @@ exports.Assign = class Assign extends Base
   # more than once.
   compileConditional: (o) ->
     [left, rite] = @variable.cacheReference o
-    new Op(@context.slice(0, -1), left, new Assign(rite, @value, '='), undefined, "?" in @context ).compile o
+    if "?" in @context then o.isExistentialEquals = true
+    new Op(@context.slice(0, -1), left, new Assign(rite, @value, '=') ).compile o
 
   # Compile the assignment from an array splice literal, using JavaScript's
   # `Array#splice` method.
@@ -1229,8 +1230,7 @@ exports.While = class While extends Base
 # Simple Arithmetic and logical operations. Performs some conversion from
 # CoffeeScript operations into their JavaScript equivalents.
 exports.Op = class Op extends Base
-  
-  constructor: (op, first, second, flip, @isExistentialEquals ) ->
+  constructor: (op, first, second, flip ) ->
     return new In first, second if op is 'in'
     if op is 'do'
       call = new Call first, first.params or []
@@ -1328,10 +1328,7 @@ exports.Op = class Op extends Base
     else
       fst = @first
       ref = fst
-    if @isExistentialEquals
-      new If(new Existence(fst).invert(), @second, type: 'if').addElse(fst).compile o
-    else
-      new If(new Existence(fst), ref, type: 'if').addElse(@second).compile o
+    new If(new Existence(fst), ref, type: 'if').addElse(@second).compile o
 
   # Compile a unary **Op**.
   compileUnary: (o) ->
@@ -1676,6 +1673,11 @@ exports.If = class If extends Base
   # force inner *else* bodies into statement form.
   compileStatement: (o) ->
     child    = del o, 'chainChild'
+    exeq     = del o, 'isExistentialEquals'
+    
+    if exeq
+      return new If(@condition.invert(), @elseBodyNode(), type: 'if').compile o
+    
     cond     = @condition.compile o, LEVEL_PAREN
     o.indent += TAB
     body     = @ensureBlock(@body).compile o

test/assignment.coffee

@@ -269,8 +269,20 @@ test "existential assignment", ->
   d ?= nonce
   eq nonce, d
 
-test "#1348, #1216: existential assignment comilation", ->
+test "#1348, #1216: existential assignment compilation", ->
   nonce = {}
   a = nonce
   b = (a ?= 0)
   eq nonce, b
+  #the first ?= compiles into a statement; the second ?= compiles to a ternary expression
+  eq a ?= b ?= 1, nonce
+  
+  e ?= f ?= g ?= 1
+  eq e + g, 2
+  
+  #need to ensure the two vars are not defined, hence the strange names;
+  # broke earlier when using c ?= d ?= 1 because `d` is declared elsewhere
+  eq und1_1348 ?= und2_1348 ?= 1, 1
+  
+  if a then a ?= 2 else a = 3
+  eq a, nonce