Fix 2295. Regexp.union [] gives wrong result in ruby 1.8 mode

jruby · Dec 10, 2014 · 2f56d95 · 2f56d95
1 parent b5ce6b9
commit 2f56d95
Showing 1 changed file with 1 addition and 0 deletions.
diff --git a/core/src/main/java/org/jruby/RubyRegexp.java b/core/src/main/java/org/jruby/RubyRegexp.java
@@ -1139,6 +1139,7 @@ public static IRubyObject union(ThreadContext context, IRubyObject recv, IRubyOb
             if (a.isNil()) return newRegexp(runtime, quote(context, recv, args).getByteList());
 
             RubyArray aa = (RubyArray)a;
+            if (aa.size() == 0) return newRegexp(runtime, ByteList.create("(?!)"));
             int len = aa.getLength();
             realArgs = new IRubyObject[len];
             for(int i = 0; i<len; i++) {