Merge pull request #297 from timcraft/string-uplus

include/natalie/string_object.hpp

@@ -163,6 +163,7 @@ class StringObject : public Object {
     Value strip(Env *) const;
     Value to_i(Env *, Value) const;
     Value upcase(Env *);
+    Value uplus(Env *);
 
     template <typename... Args>
     static StringObject *format(Env *env, const char *fmt, Args... args) {

lib/natalie/compiler/binding_gen.rb

@@ -718,6 +718,7 @@ def generate_name
 
 gen.binding('String', '*', 'StringObject', 'mul', argc: 1, pass_env: true, pass_block: false, return_type: :Object)
 gen.binding('String', '+', 'StringObject', 'add', argc: 1, pass_env: true, pass_block: false, return_type: :Object)
+gen.binding('String', '+@', 'StringObject', 'uplus', argc: 0, pass_env: true, pass_block: false, return_type: :Object)
 gen.binding('String', '<<', 'StringObject', 'ltlt', argc: 1, pass_env: true, pass_block: false, return_type: :Object)
 gen.binding('String', '<=>', 'StringObject', 'cmp', argc: 1, pass_env: true, pass_block: false, return_type: :Object)
 gen.binding('String', '==', 'StringObject', 'eq', argc: 1, pass_env: true, pass_block: false, return_type: :bool)

spec/core/string/uplus_spec.rb

@@ -0,0 +1,23 @@
+require_relative '../../spec_helper'
+
+describe 'String#+@' do
+  it 'returns an unfrozen copy of a frozen String' do
+    input  = 'foo'.freeze
+    output = +input
+
+    output.should_not.frozen?
+    output.should == 'foo'
+  end
+
+  it 'returns self if the String is not frozen' do
+    input  = 'foo'
+    output = +input
+
+    output.equal?(input).should == true
+  end
+
+  # NATFIXME: Implement fixture method and add freeze_magic_comment.rb fixture
+  xit 'returns mutable copy despite freeze-magic-comment in file' do
+    ruby_exe(fixture(__FILE__, "freeze_magic_comment.rb")).should == 'mutable'
+  end
+end

src/string_object.cpp

@@ -726,6 +726,14 @@ Value StringObject::upcase(Env *env) {
     return str;
 }
 
+Value StringObject::uplus(Env *env) {
+    if (this->is_frozen()) {
+        return this->dup(env);
+    } else {
+        return this;
+    }
+}
+
 Value StringObject::reverse(Env *env) {
     if (length() == 0)
         return new StringObject {};