Make ActiveSupport frozen string literal friendly.

The ActiveSupport test suite only passes currently if it uses the latest unreleased commits for dalli, and a patch for Builder:
https://github.com/tenderlove/builder/pull/6

Beyond that, all external dependencies (at least, to the extent they’re used by ActiveSupport) are happy, including Nokogiri as of 1.8.0.

5 files changed, 6 insertions, 6 deletions

diff --git a/activesupport/lib/active_support/xml_mini/libxml.rb b/activesupport/lib/active_support/xml_mini/libxml.rb
index d849cdfa6b..5187316389 100644
--- a/activesupport/lib/active_support/xml_mini/libxml.rb
+++ b/activesupport/lib/active_support/xml_mini/libxml.rb
@@ -53,7 +53,7 @@ module LibXML #:nodoc:
           if c.element?
             c.to_hash(node_hash)
           elsif c.text? || c.cdata?
-            node_hash[CONTENT_ROOT] ||= ""
+            node_hash[CONTENT_ROOT] ||= "".dup
             node_hash[CONTENT_ROOT] << c.content
           end
         end
diff --git a/activesupport/lib/active_support/xml_mini/libxmlsax.rb b/activesupport/lib/active_support/xml_mini/libxmlsax.rb
index f3d485da2f..b1b5517414 100644
--- a/activesupport/lib/active_support/xml_mini/libxmlsax.rb
+++ b/activesupport/lib/active_support/xml_mini/libxmlsax.rb
@@ -21,7 +21,7 @@ module ActiveSupport
       end
 
       def on_start_document
-        @hash = { CONTENT_KEY => "" }
+        @hash = { CONTENT_KEY => "".dup }
         @hash_stack = [@hash]
       end
 
@@ -31,7 +31,7 @@ module ActiveSupport
       end
 
       def on_start_element(name, attrs = {})
-        new_hash = { CONTENT_KEY => "" }.merge!(attrs)
+        new_hash = { CONTENT_KEY => "".dup }.merge!(attrs)
         new_hash[HASH_SIZE_KEY] = new_hash.size + 1
 
         case current_hash[name]
diff --git a/activesupport/lib/active_support/xml_mini/nokogiri.rb b/activesupport/lib/active_support/xml_mini/nokogiri.rb
index 63466c08b2..14176747f9 100644
--- a/activesupport/lib/active_support/xml_mini/nokogiri.rb
+++ b/activesupport/lib/active_support/xml_mini/nokogiri.rb
@@ -57,7 +57,7 @@ module ActiveSupport
             if c.element?
               c.to_hash(node_hash)
             elsif c.text? || c.cdata?
-              node_hash[CONTENT_ROOT] ||= ""
+              node_hash[CONTENT_ROOT] ||= "".dup
               node_hash[CONTENT_ROOT] << c.content
             end
           end
diff --git a/activesupport/lib/active_support/xml_mini/nokogirisax.rb b/activesupport/lib/active_support/xml_mini/nokogirisax.rb
index 54e15e6a5f..902faac312 100644
--- a/activesupport/lib/active_support/xml_mini/nokogirisax.rb
+++ b/activesupport/lib/active_support/xml_mini/nokogirisax.rb
@@ -37,7 +37,7 @@ module ActiveSupport
       end
 
       def start_element(name, attrs = [])
-        new_hash = { CONTENT_KEY => "" }.merge!(Hash[attrs])
+        new_hash = { CONTENT_KEY => "".dup }.merge!(Hash[attrs])
         new_hash[HASH_SIZE_KEY] = new_hash.size + 1
 
         case current_hash[name]
diff --git a/activesupport/lib/active_support/xml_mini/rexml.rb b/activesupport/lib/active_support/xml_mini/rexml.rb
index 03fa910fa5..30e17965a1 100644
--- a/activesupport/lib/active_support/xml_mini/rexml.rb
+++ b/activesupport/lib/active_support/xml_mini/rexml.rb
@@ -74,7 +74,7 @@ module ActiveSupport
           hash
         else
           # must use value to prevent double-escaping
-          texts = ""
+          texts = "".dup
           element.texts.each { |t| texts << t.value }
           merge!(hash, CONTENT_KEY, texts)
         end