Don't allow rb_fiber_resume to raise exception on unborn fiber.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@66611 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

cont.c

@@ -1896,9 +1896,14 @@ rb_fiber_resume(VALUE fibval, int argc, const VALUE *argv)
 {
     rb_fiber_t *fib = fiber_ptr(fibval);
 
+    if (argc == -1 && FIBER_CREATED_P(fib)) {
+        rb_raise(rb_eFiberError, "cannot raise exception on unborn fiber");
+    }
+
     if (fib->prev != 0 || fiber_is_root_p(fib)) {
 	rb_raise(rb_eFiberError, "double resume");
     }
+
     if (fib->transferred != 0) {
 	rb_raise(rb_eFiberError, "cannot resume transferred Fiber");
     }

test/ruby/test_fiber.rb

@@ -144,6 +144,7 @@ class TestFiber < Test::Unit::TestCase
     }
     assert_raise(RuntimeError){
       fib = Fiber.new{ Fiber.yield }
+      fib.resume
       fib.raise "raise and propagate"
     }
     assert_nothing_raised{