Wow seemingly I did not compile my last commit locally since I passed all tests.

enebo · enebo · commit 772832ad5899 · 2018-07-17T09:52:16.000-05:00
Add back in spreading args in prepareBlockArgsInternal with an example of
how it fails.  We may be able to change how we call higher up stream so this
spreading happens elsewhere.
diff --git a/core/src/main/java/org/jruby/ir/runtime/IRRuntimeHelpers.java b/core/src/main/java/org/jruby/ir/runtime/IRRuntimeHelpers.java
@@ -1748,7 +1748,17 @@ private static IRubyObject[] prepareBlockArgsInternal(ThreadContext context, Blo
 
         switch (block.type) {
             case LAMBDA:
-                block.getBody().getSignature().checkArity(context.runtime, args);
+                // FIXME: passing a lambda to each_with_index via enumerator seems to need this.
+                // This is fairly complicated but we should try and eliminate needing this arg spreading
+                // here (test_enum.rb:test_cycle):
+                //     cond = ->(x, i) {a << x}
+                //     @obj.each_with_index.cycle(2, &cond)
+                org.jruby.runtime.Signature sig = block.getBody().getSignature();
+                if (sig.arityValue() != -1 && sig.required() != 1) {
+                    args = toAry(context, args);
+                }
+
+                sig.checkArity(context.runtime, args);
                 return args;
             case PROC:
                 return prepareProcArgs(context, block, args);
