Drop last `default:` if it's the last branch and empty

Close #141

1 files changed, 12 insertions, 5 deletions

diff --git a/lib/compress.js b/lib/compress.js
index f4048991..efdb49fe 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -1414,11 +1414,18 @@ merge(Compressor.prototype, {
                 body: self.expression
             }).transform(compressor);
         }
-        var last_branch = self.body[self.body.length - 1];
-        if (last_branch) {
-            var stat = last_branch.body[last_branch.body.length - 1]; // last statement
-            if (stat instanceof AST_Break && loop_body(compressor.loopcontrol_target(stat.label)) === self)
-                last_branch.body.pop();
+        for(;;) {
+            var last_branch = self.body[self.body.length - 1];
+            if (last_branch) {
+                var stat = last_branch.body[last_branch.body.length - 1]; // last statement
+                if (stat instanceof AST_Break && loop_body(compressor.loopcontrol_target(stat.label)) === self)
+                    last_branch.body.pop();
+                if (last_branch instanceof AST_Default && last_branch.body.length == 0) {
+                    self.body.pop();
+                    continue;
+                }
+            }
+            break;
         }
         var exp = self.expression.evaluate(compressor);
         out: if (exp.length == 2) try {