non-symbol keys in kwargs

* class.c (separate_symbol): [EXPERIMENTAL] non-symbol key in keyword
  arguments hash causes an exception now.
  c.f. https://twitter.com/yukihiro_matz/status/1022287578995646464

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64358 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 34 insertions, 10 deletions

diff --git a/class.c b/class.c
index cb47849e96..b77974fdf2 100644
--- a/class.c
+++ b/class.c
@@ -1814,33 +1814,57 @@ unknown_keyword_error(VALUE hash, const ID *table, int keywords)
     rb_keyword_error("unknown", rb_hash_keys(hash));
 }
 
+struct extract_keywords {
+    VALUE kwdhash, nonsymkey;
+};
+
 static int
 separate_symbol(st_data_t key, st_data_t value, st_data_t arg)
 {
-    VALUE *kwdhash = (VALUE *)arg;
+    struct extract_keywords *argp = (struct extract_keywords *)arg;
+    VALUE k = (VALUE)key, v = (VALUE)value;
 
-    if (!SYMBOL_P(key)) kwdhash++;
-    if (!*kwdhash) *kwdhash = rb_hash_new();
-    rb_hash_aset(*kwdhash, (VALUE)key, (VALUE)value);
+    if (argp->kwdhash) {
+        if (UNLIKELY(!SYMBOL_P(k))) {
+            argp->nonsymkey = k;
+            return ST_STOP;
+        }
+    }
+    else if (SYMBOL_P(k)) {
+        if (UNLIKELY(argp->nonsymkey != Qundef)) {
+            argp->kwdhash = Qnil;
+            return ST_STOP;
+        }
+        argp->kwdhash = rb_hash_new();
+    }
+    else {
+        if (argp->nonsymkey == Qundef)
+            argp->nonsymkey = k;
+        return ST_CONTINUE;
+    }
+    rb_hash_aset(argp->kwdhash, k, v);
     return ST_CONTINUE;
 }
 
 VALUE
 rb_extract_keywords(VALUE *orighash)
 {
-    VALUE parthash[2] = {0, 0};
+    struct extract_keywords arg = {0, Qundef};
     VALUE hash = *orighash;
 
     if (RHASH_EMPTY_P(hash)) {
 	*orighash = 0;
 	return hash;
     }
-    st_foreach(rb_hash_tbl_raw(hash), separate_symbol, (st_data_t)&parthash);
-    *orighash = parthash[1];
-    if (parthash[1] && RBASIC_CLASS(hash) != rb_cHash) {
-	RBASIC_SET_CLASS(parthash[1], RBASIC_CLASS(hash));
+    st_foreach(rb_hash_tbl_raw(hash), separate_symbol, (st_data_t)&arg);
+    if (arg.kwdhash) {
+        if (arg.nonsymkey != Qundef) {
+            rb_raise(rb_eArgError, "non-symbol key in keyword arguments: %+"PRIsVALUE,
+                     arg.nonsymkey);
+        }
+        *orighash = 0;
     }
-    return parthash[0];
+    return arg.kwdhash;
 }
 
 int