[ruby-dev:23713] Re: define_method and $SAFE

なかだです。

At Thu, 17 Jun 2004 18:41:03 +0900,
Yukihiro Matsumoto wrote in [ruby-dev:23711]:
> |一度メソッドにした以上、再びProcに戻してもメソッドの動作に従う
> |べきでしょうか。
> 
> そう思います。メソッドがProc由来かどうかはこの際関係ないので
> はないかと。

外部の$SAFEを変更できなくなっていました。で、そのテストを作って
いて気づいたんですが、メソッドを直接呼び出したときとMethod#call
を使ったときでの振舞の違い、Methodオブジェクト内部での$SAFEの変
更は外部に影響しないというのは仕様でしょうか。

  $ ruby -e 'def inc;$SAFE+=1;end;inc;p $SAFE'
  1

  $ ruby -e 'def inc;$SAFE+=1;end;method(:inc).call;p $SAFE'
  0


* eval.c (proc_set_safe_level): not set for defined methods.


Index: eval.c
===================================================================
RCS file: /var/cvs/src/ruby/eval.c,v
retrieving revision 1.668
diff -u -2 -p -r1.668 eval.c
--- eval.c	16 Jun 2004 14:21:33 -0000	1.668
+++ eval.c	17 Jun 2004 10:56:15 -0000
@@ -7877,4 +7877,5 @@ rb_f_binding(self)
 #define PROC_TSHIFT (FL_USHIFT+1)
 #define PROC_TMASK  (FL_USER1|FL_USER2|FL_USER3)
+#define PROC_NOSAFE FL_USER4
 
 static void
@@ -7892,8 +7893,11 @@ proc_get_safe_level(data)
 }
 
+#define proc_safe_level_p(data) (!(RBASIC(data)->flags & PROC_NOSAFE))
+
 static void
 proc_set_safe_level(data)
     VALUE data;
 {
+    if (!proc_safe_level_p(data)) return;
     ruby_safe_level = proc_get_safe_level(data);
 }
@@ -8077,5 +8081,5 @@ proc_invoke(proc, args, self, klass)
     ruby_wrapper = old_wrapper;
     ruby_dyna_vars = old_dvars;
-    ruby_safe_level = safe;
+    if (proc_safe_level_p(proc)) ruby_safe_level = safe;
 
     switch (state) {
@@ -8424,5 +8428,5 @@ block_pass(self, node)
     POP_ITER();
     ruby_block = old_block;
-    ruby_safe_level = safe;
+    if (proc_safe_level_p(proc)) ruby_safe_level = safe;
 
     switch (state) {/* escape from orphan block */
@@ -9142,4 +9146,5 @@ rb_mod_define_method(argc, argv, mod)
 
 	body = proc_clone(body);
+	RBASIC(body)->flags |= PROC_NOSAFE;
 	Data_Get_Struct(body, struct BLOCK, block);
 	block->frame.last_func = id;
Index: test/ruby/test_proc.rb
===================================================================
RCS file: /var/cvs/src/ruby/test/ruby/test_proc.rb,v
retrieving revision 1.9
diff -U2 -p -d -r1.9 test_proc.rb
--- test/ruby/test_proc.rb	25 May 2004 02:54:22 -0000	1.9
+++ test/ruby/test_proc.rb	17 Jun 2004 10:58:03 -0000
@@ -92,3 +92,34 @@ class TestProc < Test::Unit::TestCase
     assert_equal(12, Proc.new{|a,&b| b.call(a)}.call(12) {|x| x})
   end
+
+  def test_safe
+    safe = $SAFE
+    c = Class.new
+    x = c.new
+
+    p = proc {
+      $SAFE += 1
+      proc {$SAFE}
+    }.call
+    assert_equal(safe, $SAFE)
+    assert_equal(safe + 1, p.call)
+    assert_equal(safe, $SAFE)
+
+    c.class_eval {define_method(:safe, p)}
+    assert_equal(safe, x.safe)
+    assert_equal(safe, x.method(:safe).call)
+    assert_equal(safe, x.method(:safe).to_proc.call)
+
+    p = proc {$SAFE += 1}
+    assert_equal(safe + 1, p.call)
+    assert_equal(safe, $SAFE)
+
+    c.class_eval {define_method(:inc, p)}
+    assert_equal(safe + 1, proc {x.inc; $SAFE}.call)
+    assert_equal(safe, $SAFE)
+    #assert_equal(safe + 1, proc {x.method(:inc).call; $SAFE}.call)
+    #assert_equal(safe, $SAFE)
+    assert_equal(safe + 1, proc {x.method(:inc).to_proc.call; $SAFE}.call)
+    assert_equal(safe, $SAFE)
+  end
 end


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