refinements in string interpolation

* compile.c (iseq_compile_each0): insert to_s method call, so that
  refinements activated at the caller should take place.
  [Feature #13812]

* insns.def (tostring): fix up converted object to a string,
  infect and fallback.

* insns.def (branchiftype): new instruction for conversion.
  branches if TOS is an instance of the given type.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@59950 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 8 insertions, 0 deletions

diff --git a/compile.c b/compile.c
index 5cf7f750fc..0e3abd71f7 100644
--- a/compile.c
+++ b/compile.c
@@ -6180,7 +6180,15 @@ iseq_compile_each0(rb_iseq_t *iseq, LINK_ANCHOR *const ret, NODE *node, int popp
 	    ADD_INSN(ret, line, pop);
 	}
 	else {
+	    const unsigned int flag = VM_CALL_FCALL;
+	    LABEL *isstr = NEW_LABEL(line);
+	    ADD_INSN(ret, line, dup);
+	    ADD_INSN2(ret, line, branchiftype, INT2FIX(T_STRING), isstr);
+	    LABEL_REF(isstr);
+	    ADD_INSN(ret, line, dup);
+	    ADD_SEND_R(ret, line, idTo_s, INT2FIX(0), NULL, INT2FIX(flag), NULL);
 	    ADD_INSN(ret, line, tostring);
+	    ADD_LABEL(ret, isstr);
 	}
 	break;
       }