+'string' and -'string' mod specifier @ method support based on Ruby 2.3

jruby · Dec 13, 2015 · 64213e6 · 64213e6
1 parent fed64fe
commit 64213e6
Showing 2 changed files with 33 additions and 4 deletions.
diff --git a/core/src/main/java/org/jruby/RubyString.java b/core/src/main/java/org/jruby/RubyString.java
@@ -1110,13 +1110,23 @@ private IRubyObject op_equalCommon(ThreadContext context, IRubyObject other) {
         return invokedynamic(context, other, OP_EQUAL, this).isTrue() ? runtime.getTrue() : runtime.getFalse();
     }
 
-    public IRubyObject op_plus(ThreadContext context, IRubyObject _str) {
-        return op_plus19(context, _str);
+    @JRubyMethod(name = "-@") // -'foo' returns frozen string
+    public final IRubyObject minus_at() {
+        return isFrozen() ? this : this.dupFrozen();
+    }
+
+    @JRubyMethod(name = "+@") // +'foo' returns modifiable string
+    public final IRubyObject plus_at() {
+        return isFrozen() ? this.dup() : this;
+    }
+
+    public IRubyObject op_plus(ThreadContext context, IRubyObject arg) {
+        return op_plus19(context, arg);
     }
 
     @JRubyMethod(name = "+", required = 1)
-    public IRubyObject op_plus19(ThreadContext context, IRubyObject _str) {
-        RubyString str = _str.convertToString();
+    public IRubyObject op_plus19(ThreadContext context, IRubyObject arg) {
+        RubyString str = arg.convertToString();
         Encoding enc = checkEncoding(str);
         RubyString resultStr = newStringNoCopy(context.runtime, StringSupport.addByteLists(value, str.value),
                 enc, CodeRangeSupport.codeRangeAnd(getCodeRange(), str.getCodeRange()));

diff --git a/test/mri/ruby/test_string.rb b/test/mri/ruby/test_string.rb
@@ -2301,6 +2301,25 @@ def test_LSHIFT_neary_long_max
     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