Default values inside destructurings

lib/parse.js

@@ -1255,8 +1255,12 @@ function parse($TEXT, options) {
                 }));
                 next();
             } else if (is("name")) {
-                children.push(_make_symbol(sym_type));
-                next();
+                children.push(new (sym_type)({
+                    name  : String(S.token.value),
+                    start : S.token,
+                    default: (next(), is("operator", "=")) ? (next(), expression(false)) : undefined,
+                    end   : S.token
+                }));
             } else {
                 children.push(expression());
             }
@@ -1483,7 +1487,21 @@ function parse($TEXT, options) {
                 continue;
             }
             
-            if (!is("punc", ":")) {
+            if (is("operator", "=")) {
+                next();
+                a.push(new AST_Assign({
+                    start: start,
+                    // Symbol class doesn't matter. This is only meant to carry the symbol name into .as_params() since this is not normally valid.
+                    left: new AST_SymbolRef({
+                        start: start,
+                        end: start,
+                        name: name
+                    }),
+                    operator: "=",
+                    right: expression(false),
+                    end: prev()
+                }));
+            } else if (!is("punc", ":")) {
                 // It's one of those object destructurings, the value is its own name
                 a.push(new AST_ObjectSymbol({
                     start: start,

test/compress/harmony.js

@@ -141,6 +141,16 @@ default_arguments: {
     expect_exact: "function x(a=6){}function x(a=6+5){}function x({foo}={},[bar]=[1]){}"
 }
 
+default_values_in_destructurings: {
+    input: {
+        function x({a=(4), b}) {}
+        function x([b, c=(12)]) {}
+        var { x = (6), y } = x;
+        var [ x, y = (6) ] = x;
+    }
+    expect_exact: "function x({a=4,b}){}function x([b,c=12]){}var{x=6,y}=x;var[x,y=6]=x;"
+}
+
 concise_methods: {
     input: {
         x = {