Merge branch 'master' into adequaterecord

* master: (74 commits)
  [ci skip] builtin -> built-in
  Fix code indentation and improve formatting
  Grammar fix in Getting Started Guide
  Make URL escaping more consistent
  Optimize URI escaping
  Always escape string passed to url helper.
  Remove statement assuming coffee shop/public space wifi is inherently insecure
  Don't rely on Arel master in bug report template [ci skip]
  wrap methods in backticks [ci skip]
  "subhash" --> "sub-hash"
  multibyte_conformance.rb --> multibyte_conformance_test.rb
  Fix inconsistent behavior from String#first/#last
  `@destroyed` should always be set to `false` when an object is duped.
  remove warning `warning: ambiguous first argument; put parentheses or even spaces`
  :uglify -> :uglifier
  Regression test for irregular inflection on has_many
  Singularize association names before camelization
  Fix spelling and proper nouns
  Optimize select_value, select_values, select_rows and dry up checking whether to exec with cache for Postgresql adapter
  Include default rails protect_from_forgery with: :exception
  ...

Conflicts:
	activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
	activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb

6 files changed, 21 insertions, 8 deletions

diff --git a/activesupport/lib/active_support/core_ext/load_error.rb b/activesupport/lib/active_support/core_ext/load_error.rb
index fe24f3716d..768b980f21 100644
--- a/activesupport/lib/active_support/core_ext/load_error.rb
+++ b/activesupport/lib/active_support/core_ext/load_error.rb
@@ -7,6 +7,7 @@ class LoadError
   ]
 
   unless method_defined?(:path)
+    # Returns the path which was unable to be loaded.
     def path
       @path ||= begin
         REGEXPS.find do |regex|
@@ -17,9 +18,11 @@ class LoadError
     end
   end
 
+  # Returns true if the given path name (except perhaps for the ".rb"
+  # extension) is the missing file which caused the exception to be raised.
   def is_missing?(location)
     location.sub(/\.rb$/, '') == path.sub(/\.rb$/, '')
   end
 end
 
-MissingSourceFile = LoadError
\ No newline at end of file
+MissingSourceFile = LoadError
diff --git a/activesupport/lib/active_support/core_ext/object/duplicable.rb b/activesupport/lib/active_support/core_ext/object/duplicable.rb
index 9cd7485e2e..3d2c809c9f 100644
--- a/activesupport/lib/active_support/core_ext/object/duplicable.rb
+++ b/activesupport/lib/active_support/core_ext/object/duplicable.rb
@@ -78,6 +78,9 @@ end
 
 require 'bigdecimal'
 class BigDecimal
+  # Needed to support Ruby 1.9.x, as it doesn't allow dup on BigDecimal, instead
+  # raises TypeError exception. Checking here on the runtime whether BigDecimal
+  # will allow dup or not.
   begin
     BigDecimal.new('4.56').dup
 
diff --git a/activesupport/lib/active_support/core_ext/string/access.rb b/activesupport/lib/active_support/core_ext/string/access.rb
index 6018fd9641..ebd0dd3fc7 100644
--- a/activesupport/lib/active_support/core_ext/string/access.rb
+++ b/activesupport/lib/active_support/core_ext/string/access.rb
@@ -64,7 +64,7 @@ class String
 
   # Returns the first character. If a limit is supplied, returns a substring
   # from the beginning of the string until it reaches the limit value. If the
-  # given limit is greater than or equal to the string length, returns self.
+  # given limit is greater than or equal to the string length, returns a copy of self.
   #
   #   str = "hello"
   #   str.first    # => "h"
@@ -76,7 +76,7 @@ class String
     if limit == 0
       ''
     elsif limit >= size
-      self
+      self.dup
     else
       to(limit - 1)
     end
@@ -84,7 +84,7 @@ class String
 
   # Returns the last character of the string. If a limit is supplied, returns a substring
   # from the end of the string until it reaches the limit value (counting backwards). If
-  # the given limit is greater than or equal to the string length, returns self.
+  # the given limit is greater than or equal to the string length, returns a copy of self.
   #
   #   str = "hello"
   #   str.last    # => "o"
@@ -96,7 +96,7 @@ class String
     if limit == 0
       ''
     elsif limit >= size
-      self
+      self.dup
     else
       from(-limit)
     end
diff --git a/activesupport/lib/active_support/core_ext/thread.rb b/activesupport/lib/active_support/core_ext/thread.rb
index ac1ffa4128..4cd6634558 100644
--- a/activesupport/lib/active_support/core_ext/thread.rb
+++ b/activesupport/lib/active_support/core_ext/thread.rb
@@ -62,6 +62,13 @@ class Thread
     _locals.has_key?(key.to_sym)
   end
 
+  # Freezes the thread so that thread local variables cannot be set via
+  # Thread#thread_variable_set, nor can fiber local variables be set.
+  #
+  #   me = Thread.current
+  #   me.freeze
+  #   me.thread_variable_set(:oliver, "a")  #=> RuntimeError: can't modify frozen thread locals
+  #   me[:oliver] = "a"                     #=> RuntimeError: can't modify frozen thread locals
   def freeze
     _locals.freeze
     super
diff --git a/activesupport/lib/active_support/core_ext/time/conversions.rb b/activesupport/lib/active_support/core_ext/time/conversions.rb
index 9fd26156c7..dbf1f2f373 100644
--- a/activesupport/lib/active_support/core_ext/time/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/time/conversions.rb
@@ -20,7 +20,7 @@ class Time
     :iso8601      => lambda { |time| time.iso8601 }
   }
 
-  # Converts to a formatted string. See DATE_FORMATS for builtin formats.
+  # Converts to a formatted string. See DATE_FORMATS for built-in formats.
   #
   # This method is aliased to <tt>to_s</tt>.
   #
diff --git a/activesupport/lib/active_support/inflector/methods.rb b/activesupport/lib/active_support/inflector/methods.rb
index 6229d15619..94bda511bc 100644
--- a/activesupport/lib/active_support/inflector/methods.rb
+++ b/activesupport/lib/active_support/inflector/methods.rb
@@ -173,7 +173,7 @@ module ActiveSupport
     #   'ActiveRecord::CoreExtensions::String::Inflections'.demodulize # => "Inflections"
     #   'Inflections'.demodulize                                       # => "Inflections"
     #   '::Inflections'.demodulize                                     # => "Inflections"
-    #   ''.demodulize                                                  # => ''
+    #   ''.demodulize                                                  # => ""
     #
     # See also +deconstantize+.
     def demodulize(path)
@@ -230,7 +230,7 @@ module ActiveSupport
     def constantize(camel_cased_word)
       names = camel_cased_word.split('::')
 
-      # Trigger a builtin NameError exception including the ill-formed constant in the message.
+      # Trigger a built-in NameError exception including the ill-formed constant in the message.
       Object.const_get(camel_cased_word) if names.empty?
 
       # Remove the first blank element in case of '::ClassName' notation.