Correct destructured parameter default evaluation order with an incre…

…menting variable (or more generally any complicated parameter that isComplex)
jashkenas · Jan 24, 2017 · 49ccded · 49ccded
1 parent dbd8274
commit 49ccded
Show file tree

Hide file tree

Showing 3 changed files with 9 additions and 3 deletions.
diff --git a/lib/coffee-script/nodes.js b/lib/coffee-script/nodes.js
diff --git a/src/nodes.coffee b/src/nodes.coffee
@@ -2112,7 +2112,7 @@ exports.Param = class Param extends Base
     @reference = node
 
   isComplex: ->
-    @name.isComplex() or @value instanceof Call
+    @name.isComplex() or (@value?.isComplex? and @value.isComplex())
 
   # Iterates the name or names of a `Param`.
   # In a sense, a destructured parameter represents multiple JS parameters. This

diff --git a/test/functions.coffee b/test/functions.coffee
@@ -342,7 +342,12 @@ test "#1038 Optimize trailing return statements", ->
                                                    return
                                                  """)
 
-test "#4406 Destructured parameter default evaluation order", ->
+test "#4406 Destructured parameter default evaluation order with incrementing variable", ->
+  i = 0
+  f = ({ a = ++i }, b = ++i) -> [a, b]
+  arrayEq f({}), [1, 2]
+
+test "#4406 Destructured parameter default evaluation order with generator function", ->
   current = 0
   next    = -> ++current
   foo = ({ a = next() }, b = next()) -> [ a, b ]