Fix more keyword separation issues

This fixes instance_exec and similar methods. It also fixes
Enumerator::Yielder#yield, rb_yield_block, and a couple of cases
with Proc#{<<,>>}.

This support requires the addition of rb_yield_values_kw, similar to
rb_yield_values2, for passing the keyword flag.

Unlike earlier attempts at this, this does not modify the rb_block_call_func
type or add a separate function type.  The functions of type
rb_block_call_func are called by Ruby with a separate VM frame, and we can
get the keyword flag information from the VM frame flags, so it doesn't need
to be passed as a function argument.

These changes require the following VM functions accept a keyword flag:

* vm_yield_with_cref
* vm_yield
* vm_yield_with_block

1 files changed, 10 insertions, 6 deletions

diff --git a/vm.c b/vm.c
index f26ab73dfe..a442e9f553 100644
--- a/vm.c
+++ b/vm.c
@@ -1164,26 +1164,26 @@ check_block_handler(rb_execution_context_t *ec)
 }
 
 static VALUE
-vm_yield_with_cref(rb_execution_context_t *ec, int argc, const VALUE *argv, const rb_cref_t *cref, int is_lambda)
+vm_yield_with_cref(rb_execution_context_t *ec, int argc, const VALUE *argv, int kw_splat, const rb_cref_t *cref, int is_lambda)
 {
     return invoke_block_from_c_bh(ec, check_block_handler(ec),
-                                  argc, argv, VM_NO_KEYWORDS, VM_BLOCK_HANDLER_NONE,
+                                  argc, argv, kw_splat, VM_BLOCK_HANDLER_NONE,
 				  cref, is_lambda, FALSE);
 }
 
 static VALUE
-vm_yield(rb_execution_context_t *ec, int argc, const VALUE *argv)
+vm_yield(rb_execution_context_t *ec, int argc, const VALUE *argv, int kw_splat)
 {
     return invoke_block_from_c_bh(ec, check_block_handler(ec),
-                                  argc, argv, VM_NO_KEYWORDS, VM_BLOCK_HANDLER_NONE,
+                                  argc, argv, kw_splat, VM_BLOCK_HANDLER_NONE,
 				  NULL, FALSE, FALSE);
 }
 
 static VALUE
-vm_yield_with_block(rb_execution_context_t *ec, int argc, const VALUE *argv, VALUE block_handler)
+vm_yield_with_block(rb_execution_context_t *ec, int argc, const VALUE *argv, VALUE block_handler, int kw_splat)
 {
     return invoke_block_from_c_bh(ec, check_block_handler(ec),
-                                  argc, argv, VM_NO_KEYWORDS, block_handler,
+                                  argc, argv, kw_splat, block_handler,
 				  NULL, FALSE, FALSE);
 }
 
@@ -1213,6 +1213,10 @@ invoke_block_from_c_proc(rb_execution_context_t *ec, const rb_proc_t *proc,
       case block_type_iseq:
         return invoke_iseq_block_from_c(ec, &block->as.captured, self, argc, argv, kw_splat, passed_block_handler, NULL, is_lambda, me);
       case block_type_ifunc:
+        if (kw_splat == 1 && RHASH_EMPTY_P(argv[argc-1])) {
+            argc--;
+            kw_splat = 2;
+        }
         return vm_yield_with_cfunc(ec, &block->as.captured, self, argc, argv, kw_splat, passed_block_handler, me);
       case block_type_symbol:
 	return vm_yield_with_symbol(ec, block->as.symbol, argc, argv, kw_splat, passed_block_handler);