diff options
| -rw-r--r-- | ChangeLog | 6 | ||||
| -rw-r--r-- | string.c | 42 | ||||
| -rw-r--r-- | test/ruby/test_string.rb | 18 |
3 files changed, 66 insertions, 0 deletions
@@ -1,3 +1,9 @@ +Mon Dec 7 23:45:20 2015 Koichi Sasada <ko1@atdot.net> + + * string.c: introduce String#+@ and String#-@ to control + String mutability. + [Feature #11782] + Mon Dec 7 23:39:49 2015 Ben Miller <bjmllr@gmail.com> * parse.y: add heredoc <<~ syntax. [Feature #9098] @@ -2227,6 +2227,46 @@ rb_str_freeze(VALUE str) return rb_obj_freeze(str); } + +/* + * call-seq: + * +str -> str (mutable) + * + * If the string is frozen, then return duplicated mutable string. + * + * If the string is not frozen, then return the string itself. + */ +static VALUE +str_uplus(VALUE str) +{ + if (OBJ_FROZEN(str)) { + return rb_str_dup(str); + } + else { + return str; + } +} + +/* + * call-seq: + * -str -> str (frozen) + * + * If the string is frozen, then return the string itself. + * + * If the string is not frozen, then duplicate the string + * freeze it and return it. + */ +static VALUE +str_uminus(VALUE str) +{ + if (OBJ_FROZEN(str)) { + return str; + } + else { + return rb_str_freeze(rb_str_dup(str)); + } +} + RUBY_ALIAS_FUNCTION(rb_str_dup_frozen(VALUE str), rb_str_new_frozen, (str)) #define rb_str_dup_frozen rb_str_new_frozen @@ -9295,6 +9335,8 @@ Init_String(void) rb_define_method(rb_cString, "scrub", str_scrub, -1); rb_define_method(rb_cString, "scrub!", str_scrub_bang, -1); rb_define_method(rb_cString, "freeze", rb_str_freeze, 0); + rb_define_method(rb_cString, "+@", str_uplus, 0); + rb_define_method(rb_cString, "-@", str_uminus, 0); rb_define_method(rb_cString, "to_i", rb_str_to_i, -1); rb_define_method(rb_cString, "to_f", rb_str_to_f, 0); diff --git a/test/ruby/test_string.rb b/test/ruby/test_string.rb index 7627fe12dc..824c0e6b1c 100644 --- a/test/ruby/test_string.rb +++ b/test/ruby/test_string.rb @@ -2252,6 +2252,24 @@ class TestString < Test::Unit::TestCase end; end if [0].pack("l!").bytesize < [nil].pack("p").bytesize # enable only when string size range is smaller than memory space + + def test_uplus_minus + str = "foo" + assert_equal(false, str.frozen?) + assert_equal(false, (+str).frozen?) + assert_equal(true, (-str).frozen?) + + assert_equal(str.object_id, (+str).object_id) + assert_not_equal(str.object_id, (-str).object_id) + + str = "bar".freeze + assert_equal(true, str.frozen?) + assert_equal(false, (+str).frozen?) + assert_equal(true, (-str).frozen?) + + assert_not_equal(str.object_id, (+str).object_id) + assert_equal(str.object_id, (-str).object_id) + end end class TestString2 < TestString |