From: nobu@...
Date: 2006-09-03T14:20:00+09:00
Subject: [ruby-dev:29431] Re: method_missing in Ruby 1.9.0

なかだです。

At Sun, 3 Sep 2006 09:55:59 +0900,
Masaki Suketa wrote in [ruby-dev:29420]:
> 次のスクリプトが、ruby 1.9.0 (2006-09-03)で falseと出力されます。
>   class Foo
>     def method_missing(id, *arg)
>       p id # => false
>     end
>   end
>   
>   foo = Foo.new
>   foo.visible = true

たまたまfalse(== 0)になっただけで、実際には不定値ですね。


Index: gc.c
===================================================================
RCS file: /cvs/ruby/src/ruby/gc.c,v
retrieving revision 1.248
diff -p -U 2 -r1.248 gc.c
--- gc.c	2 Sep 2006 15:05:27 -0000	1.248
+++ gc.c	3 Sep 2006 01:12:58 -0000
@@ -1382,5 +1382,5 @@ garbage_collect(void)
 #endif
     rb_gc_mark_threads();
-    rb_gc_mark_symbols();
+    rb_gc_mark_symbols(0);
 
     /* mark protected global variables */
Index: intern.h
===================================================================
RCS file: /cvs/ruby/src/ruby/intern.h,v
retrieving revision 1.199
diff -p -U 2 -r1.199 intern.h
--- intern.h	31 Aug 2006 08:24:36 -0000	1.199
+++ intern.h	3 Sep 2006 01:12:33 -0000
@@ -259,4 +259,5 @@ int ruby_cleanup(int);
 int ruby_exec(void);
 void rb_gc_mark_threads(void);
+void rb_gc_mark_symbols(int);
 void rb_thread_start_timer(void);
 void rb_thread_stop_timer(void);
Index: parse.y
===================================================================
RCS file: /cvs/ruby/src/ruby/parse.y,v
retrieving revision 1.456
diff -p -U 2 -r1.456 parse.y
--- parse.y	2 Sep 2006 15:05:27 -0000	1.456
+++ parse.y	3 Sep 2006 05:10:38 -0000
@@ -6030,5 +6030,4 @@ parser_yylex(struct parser_params *parse
 	}
 	if (c == '>') {
-	    enum lex_state_e state = lex_state;
 	    lex_state = EXPR_ARG;
 	    return tLAMBDA;
@@ -8379,4 +8378,13 @@ rb_symname_p(const char *name)
 }
 
+static void
+register_symid(VALUE sym, ID id)
+{
+    RBASIC(sym)->klass = rb_cSymbol;
+    OBJ_FREEZE(sym);
+    st_add_direct(global_symbols.sym_id, (st_data_t)sym, id);
+    st_add_direct(global_symbols.id_sym, id, (st_data_t)sym);
+}
+
 ID
 rb_intern2(const char *name, long len)
@@ -8451,8 +8459,5 @@ rb_intern2(const char *name, long len)
     id |= ++global_symbols.last_id << ID_SCOPE_SHIFT;
   id_register:
-    RBASIC(sym)->klass = rb_cSymbol;
-    OBJ_FREEZE(sym);
-    st_add_direct(global_symbols.sym_id, (st_data_t)sym, id);
-    st_add_direct(global_symbols.id_sym, id, (st_data_t)sym);
+    register_symid(sym, id);
     return id;
 }
@@ -8467,12 +8472,25 @@ VALUE
 rb_id2sym(ID id)
 {
-    VALUE data;
+    VALUE sym;
+    st_data_t data;
 
     if (st_lookup(global_symbols.id_sym, id, &data)) {
-	if (!RBASIC(data)->klass) {
-	    RBASIC(data)->klass = rb_cSymbol;
+	sym = (VALUE)data;
+	if (!RBASIC(sym)->klass) {
+	    RBASIC(sym)->klass = rb_cSymbol;
 	}
-	return data;
     }
+    else {
+	if (!is_attrset_id(id)) return Qnil;
+	id &= ~ID_SCOPE_MASK;
+	if (!st_lookup(global_symbols.id_sym, (id | ID_LOCAL), &data) &&
+	    !st_lookup(global_symbols.id_sym, (id | ID_CONST), &data)) {
+	    return Qnil;
+	}
+	sym = rb_str_dup((VALUE)data);
+	rb_str_cat(sym, "=", 1);
+	register_symid(sym, (id | ID_ATTRSET));
+    }
+    return sym;
 }
 
@@ -8490,6 +8508,5 @@ const char *
 rb_id2name(ID id)
 {
-    const char *name;
-    st_data_t data;
+    VALUE sym;
 
     if (id < tLAST_TOKEN) {
@@ -8502,24 +8519,7 @@ rb_id2name(ID id)
     }
 
-    if (st_lookup(global_symbols.id_sym, id, &data))
-	return RSTRING_PTR(data);
-
-    if (is_attrset_id(id)) {
-	ID id2 = (id & ~ID_SCOPE_MASK) | ID_LOCAL;
-
-      again:
-	name = rb_id2name(id2);
-	if (name) {
-	    char *buf = ALLOCA_N(char, strlen(name)+2);
-
-	    strcpy(buf, name);
-	    strcat(buf, "=");
-	    rb_intern(buf);
-	    return rb_id2name(id);
-	}
-	if (is_local_id(id2)) {
-	    id2 = (id & ~ID_SCOPE_MASK) | ID_CONST;
-	    goto again;
-	}
+    sym = rb_id2sym(id);
+    if (!NIL_P(sym)) {
+	return RSTRING_PTR(sym);
     }
     return 0;


-- 
--- 僕の前にBugはない。
--- 僕の後ろにBugはできる。
    中田 伸悦