Initial pass at removing dead 1.8.x code from Active Support.

There are a bunch of other implicit branches that adds
1.8.x specific code that still needs to be removed. Pull
requests for those cases are welcome.

27 files changed, 118 insertions, 760 deletions

diff --git a/activesupport/lib/active_support/core_ext/date/calculations.rb b/activesupport/lib/active_support/core_ext/date/calculations.rb
index f0f67765c6..2212e0b3ca 100644
--- a/activesupport/lib/active_support/core_ext/date/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/date/calculations.rb
@@ -7,24 +7,6 @@ require 'active_support/core_ext/time/zones'
 class Date
   DAYS_INTO_WEEK = { :monday => 0, :tuesday => 1, :wednesday => 2, :thursday => 3, :friday => 4, :saturday => 5, :sunday => 6 }
 
-  if RUBY_VERSION < '1.9'
-    undef :>>
-
-    # Backported from 1.9. The one in 1.8 leads to incorrect next_month and
-    # friends for dates where the calendar reform is involved. It additionally
-    # prevents an infinite loop fixed in r27013.
-    def >>(n)
-      y, m = (year * 12 + (mon - 1) + n).divmod(12)
-      m,   = (m + 1)                    .divmod(1)
-      d = mday
-      until jd2 = self.class.valid_civil?(y, m, d, start)
-        d -= 1
-        raise ArgumentError, 'invalid date' unless d > 0
-      end
-      self + (jd2 - jd)
-    end
-  end
-
   class << self
     # Returns a new Date representing the date 1 day ago (i.e. yesterday's date).
     def yesterday
diff --git a/activesupport/lib/active_support/core_ext/date/conversions.rb b/activesupport/lib/active_support/core_ext/date/conversions.rb
index 338104fd05..3262c254f7 100644
--- a/activesupport/lib/active_support/core_ext/date/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/date/conversions.rb
@@ -63,12 +63,6 @@ class Date
   alias_method :default_inspect, :inspect
   alias_method :inspect, :readable_inspect
 
-  # A method to keep Time, Date and DateTime instances interchangeable on conversions.
-  # In this case, it simply returns +self+.
-  def to_date
-    self
-  end if RUBY_VERSION < '1.9'
-
   # Converts a Date instance to a Time, where the time is set to the beginning of the day.
   # The timezone can be either :local or :utc (default :local).
   #
@@ -83,23 +77,6 @@ class Date
     ::Time.send("#{form}_time", year, month, day)
   end
 
-  # Converts a Date instance to a DateTime, where the time is set to the beginning of the day
-  # and UTC offset is set to 0.
-  #
-  # ==== Examples
-  #   date = Date.new(2007, 11, 10)  # => Sat, 10 Nov 2007
-  #
-  #   date.to_datetime               # => Sat, 10 Nov 2007 00:00:00 0000
-  def to_datetime
-    ::DateTime.civil(year, month, day, 0, 0, 0, 0)
-  end if RUBY_VERSION < '1.9'
-
-  def iso8601
-    strftime('%F')
-  end if RUBY_VERSION < '1.9'
-
-  alias_method :rfc3339, :iso8601 if RUBY_VERSION < '1.9'
-
   def xmlschema
     to_time_in_current_zone.xmlschema
   end
diff --git a/activesupport/lib/active_support/core_ext/date_time/calculations.rb b/activesupport/lib/active_support/core_ext/date_time/calculations.rb
index 48cf1a435d..1a3cf66a1b 100644
--- a/activesupport/lib/active_support/core_ext/date_time/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/date_time/calculations.rb
@@ -1,5 +1,3 @@
-require 'rational' unless RUBY_VERSION >= '1.9.2'
-
 class DateTime
   class << self
     # DateTimes aren't aware of DST rules, so use a consistent non-DST offset when creating a DateTime with an offset in the local zone
diff --git a/activesupport/lib/active_support/core_ext/date_time/conversions.rb b/activesupport/lib/active_support/core_ext/date_time/conversions.rb
index ca899c714c..851012e3bf 100644
--- a/activesupport/lib/active_support/core_ext/date_time/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/date_time/conversions.rb
@@ -66,7 +66,7 @@ class DateTime
   # Attempts to convert self to a Ruby Time object; returns self if out of range of Ruby Time class.
   # If self has an offset other than 0, self will just be returned unaltered, since there's no clean way to map it to a Time.
   def to_time
-    self.offset == 0 ? ::Time.utc_time(year, month, day, hour, min, sec, sec_fraction * (RUBY_VERSION < '1.9' ? 86400000000 : 1000000)) : self
+    self.offset == 0 ? ::Time.utc_time(year, month, day, hour, min, sec, sec_fraction * 1000000) : self
   end
 
   # To be able to keep Times, Dates and DateTimes interchangeable on conversions.
diff --git a/activesupport/lib/active_support/core_ext/enumerable.rb b/activesupport/lib/active_support/core_ext/enumerable.rb
index d9856f2e84..ccd0e9692d 100644
--- a/activesupport/lib/active_support/core_ext/enumerable.rb
+++ b/activesupport/lib/active_support/core_ext/enumerable.rb
@@ -1,41 +1,4 @@
-require 'active_support/ordered_hash'
-
 module Enumerable
-  # Ruby 1.8.7 introduces group_by, but the result isn't ordered. Override it.
-  remove_method(:group_by) if [].respond_to?(:group_by) && RUBY_VERSION < '1.9'
-
-  # Collect an enumerable into sets, grouped by the result of a block. Useful,
-  # for example, for grouping records by date.
-  #
-  # Example:
-  #
-  #   latest_transcripts.group_by(&:day).each do |day, transcripts|
-  #     p "#{day} -> #{transcripts.map(&:class).join(', ')}"
-  #   end
-  #   "2006-03-01 -> Transcript"
-  #   "2006-02-28 -> Transcript"
-  #   "2006-02-27 -> Transcript, Transcript"
-  #   "2006-02-26 -> Transcript, Transcript"
-  #   "2006-02-25 -> Transcript"
-  #   "2006-02-24 -> Transcript, Transcript"
-  #   "2006-02-23 -> Transcript"
-  def group_by
-    return to_enum :group_by unless block_given?
-    assoc = ActiveSupport::OrderedHash.new
-
-    each do |element|
-      key = yield(element)
-
-      if assoc.has_key?(key)
-        assoc[key] << element
-      else
-        assoc[key] = [element]
-      end
-    end
-
-    assoc
-  end unless [].respond_to?(:group_by)
-
   # Calculates a sum from the elements. Examples:
   #
   #  payments.sum { |p| p.price * p.tax_rate }
diff --git a/activesupport/lib/active_support/core_ext/exception.rb b/activesupport/lib/active_support/core_ext/exception.rb
index ef801e713d..ba7757ea07 100644
--- a/activesupport/lib/active_support/core_ext/exception.rb
+++ b/activesupport/lib/active_support/core_ext/exception.rb
@@ -1,3 +1,3 @@
 module ActiveSupport
-  FrozenObjectError = RUBY_VERSION < '1.9' ? TypeError : RuntimeError
+  FrozenObjectError = RuntimeError
 end
diff --git a/activesupport/lib/active_support/core_ext/module/introspection.rb b/activesupport/lib/active_support/core_ext/module/introspection.rb
index c08ad251dd..1893a9cfa6 100644
--- a/activesupport/lib/active_support/core_ext/module/introspection.rb
+++ b/activesupport/lib/active_support/core_ext/module/introspection.rb
@@ -57,27 +57,8 @@ class Module
     parents
   end
 
-  if RUBY_VERSION < '1.9'
-    # Returns the constants that have been defined locally by this object and
-    # not in an ancestor. This method is exact if running under Ruby 1.9. In
-    # previous versions it may miss some constants if their definition in some
-    # ancestor is identical to their definition in the receiver.
-    def local_constants
-      inherited = {}
-
-      ancestors.each do |anc|
-        next if anc == self
-        anc.constants.each { |const| inherited[const] = anc.const_get(const) }
-      end
-
-      constants.select do |const|
-        !inherited.key?(const) || inherited[const].object_id != const_get(const).object_id
-      end
-    end
-  else
-    def local_constants #:nodoc:
-      constants(false)
-    end
+  def local_constants #:nodoc:
+    constants(false)
   end
 
   # Returns the names of the constants defined locally rather than the
diff --git a/activesupport/lib/active_support/core_ext/object/instance_variables.rb b/activesupport/lib/active_support/core_ext/object/instance_variables.rb
index eda9694614..66caf9bec8 100644
--- a/activesupport/lib/active_support/core_ext/object/instance_variables.rb
+++ b/activesupport/lib/active_support/core_ext/object/instance_variables.rb
@@ -23,11 +23,7 @@ class Object
   #   end
   #
   #   C.new(0, 1).instance_variable_names # => ["@y", "@x"]
-  if RUBY_VERSION >= '1.9'
-    def instance_variable_names
-      instance_variables.map { |var| var.to_s }
-    end
-  else
-    alias_method :instance_variable_names, :instance_variables
+  def instance_variable_names
+    instance_variables.map { |var| var.to_s }
   end
 end
diff --git a/activesupport/lib/active_support/core_ext/range.rb b/activesupport/lib/active_support/core_ext/range.rb
index 2428a02242..c0736f3a44 100644
--- a/activesupport/lib/active_support/core_ext/range.rb
+++ b/activesupport/lib/active_support/core_ext/range.rb
@@ -2,4 +2,3 @@ require 'active_support/core_ext/range/blockless_step'
 require 'active_support/core_ext/range/conversions'
 require 'active_support/core_ext/range/include_range'
 require 'active_support/core_ext/range/overlaps'
-require 'active_support/core_ext/range/cover'
diff --git a/activesupport/lib/active_support/core_ext/range/cover.rb b/activesupport/lib/active_support/core_ext/range/cover.rb
deleted file mode 100644
index 3a182cddd2..0000000000
--- a/activesupport/lib/active_support/core_ext/range/cover.rb
+++ /dev/null
@@ -1,3 +0,0 @@
-class Range
-  alias_method(:cover?, :include?) unless instance_methods.include?(:cover?)
-end
diff --git a/activesupport/lib/active_support/core_ext/string/encoding.rb b/activesupport/lib/active_support/core_ext/string/encoding.rb
index d4781bfe0c..236f72e933 100644
--- a/activesupport/lib/active_support/core_ext/string/encoding.rb
+++ b/activesupport/lib/active_support/core_ext/string/encoding.rb
@@ -1,11 +1,5 @@
 class String
-  if defined?(Encoding) && "".respond_to?(:encode)
-    def encoding_aware?
-      true
-    end
-  else
-    def encoding_aware?
-      false
-    end
+  def encoding_aware?
+    true
   end
 end
\ No newline at end of file
diff --git a/activesupport/lib/active_support/core_ext/string/multibyte.rb b/activesupport/lib/active_support/core_ext/string/multibyte.rb
index 400db2ce39..4e7824ad74 100644
--- a/activesupport/lib/active_support/core_ext/string/multibyte.rb
+++ b/activesupport/lib/active_support/core_ext/string/multibyte.rb
@@ -2,71 +2,55 @@
 require 'active_support/multibyte'
 
 class String
-  if RUBY_VERSION >= "1.9"
-    # == Multibyte proxy
-    #
-    # +mb_chars+ is a multibyte safe proxy for string methods.
-    #
-    # In Ruby 1.8 and older it creates and returns an instance of the ActiveSupport::Multibyte::Chars class which
-    # encapsulates the original string. A Unicode safe version of all the String methods are defined on this proxy
-    # class. If the proxy class doesn't respond to a certain method, it's forwarded to the encapsulated string.
-    #
-    #   name = 'Claus Müller'
-    #   name.reverse # => "rell??M sualC"
-    #   name.length  # => 13
-    #
-    #   name.mb_chars.reverse.to_s # => "rellüM sualC"
-    #   name.mb_chars.length       # => 12
-    #
-    # In Ruby 1.9 and newer +mb_chars+ returns +self+ because String is (mostly) encoding aware. This means that
-    # it becomes easy to run one version of your code on multiple Ruby versions.
-    #
-    # == Method chaining
-    #
-    # All the methods on the Chars proxy which normally return a string will return a Chars object. This allows
-    # method chaining on the result of any of these methods.
-    #
-    #   name.mb_chars.reverse.length # => 12
-    #
-    # == Interoperability and configuration
-    #
-    # The Chars object tries to be as interchangeable with String objects as possible: sorting and comparing between
-    # String and Char work like expected. The bang! methods change the internal string representation in the Chars
-    # object. Interoperability problems can be resolved easily with a +to_s+ call.
-    #
-    # For more information about the methods defined on the Chars proxy see ActiveSupport::Multibyte::Chars. For
-    # information about how to change the default Multibyte behavior see ActiveSupport::Multibyte.
-    def mb_chars
-      if ActiveSupport::Multibyte.proxy_class.consumes?(self)
-        ActiveSupport::Multibyte.proxy_class.new(self)
-      else
-        self
-      end
-    end
-
-    def is_utf8?
-      case encoding
-      when Encoding::UTF_8
-        valid_encoding?
-      when Encoding::ASCII_8BIT, Encoding::US_ASCII
-        dup.force_encoding(Encoding::UTF_8).valid_encoding?
-      else
-        false
-      end
-    end
-  else
-    def mb_chars
-      if ActiveSupport::Multibyte.proxy_class.wants?(self)
-        ActiveSupport::Multibyte.proxy_class.new(self)
-      else
-        self
-      end
+  # == Multibyte proxy
+  #
+  # +mb_chars+ is a multibyte safe proxy for string methods.
+  #
+  # In Ruby 1.8 and older it creates and returns an instance of the ActiveSupport::Multibyte::Chars class which
+  # encapsulates the original string. A Unicode safe version of all the String methods are defined on this proxy
+  # class. If the proxy class doesn't respond to a certain method, it's forwarded to the encapsulated string.
+  #
+  #   name = 'Claus Müller'
+  #   name.reverse # => "rell??M sualC"
+  #   name.length  # => 13
+  #
+  #   name.mb_chars.reverse.to_s # => "rellüM sualC"
+  #   name.mb_chars.length       # => 12
+  #
+  # In Ruby 1.9 and newer +mb_chars+ returns +self+ because String is (mostly) encoding aware. This means that
+  # it becomes easy to run one version of your code on multiple Ruby versions.
+  #
+  # == Method chaining
+  #
+  # All the methods on the Chars proxy which normally return a string will return a Chars object. This allows
+  # method chaining on the result of any of these methods.
+  #
+  #   name.mb_chars.reverse.length # => 12
+  #
+  # == Interoperability and configuration
+  #
+  # The Chars object tries to be as interchangeable with String objects as possible: sorting and comparing between
+  # String and Char work like expected. The bang! methods change the internal string representation in the Chars
+  # object. Interoperability problems can be resolved easily with a +to_s+ call.
+  #
+  # For more information about the methods defined on the Chars proxy see ActiveSupport::Multibyte::Chars. For
+  # information about how to change the default Multibyte behavior see ActiveSupport::Multibyte.
+  def mb_chars
+    if ActiveSupport::Multibyte.proxy_class.consumes?(self)
+      ActiveSupport::Multibyte.proxy_class.new(self)
+    else
+      self
     end
+  end
 
-    # Returns true if the string has UTF-8 semantics (a String used for purely byte resources is unlikely to have
-    # them), returns false otherwise.
-    def is_utf8?
-      ActiveSupport::Multibyte::Chars.consumes?(self)
+  def is_utf8?
+    case encoding
+    when Encoding::UTF_8
+      valid_encoding?
+    when Encoding::ASCII_8BIT, Encoding::US_ASCII
+      dup.force_encoding(Encoding::UTF_8).valid_encoding?
+    else
+      false
     end
   end
 end
diff --git a/activesupport/lib/active_support/core_ext/uri.rb b/activesupport/lib/active_support/core_ext/uri.rb
index ee991e3439..0b219ce44a 100644
--- a/activesupport/lib/active_support/core_ext/uri.rb
+++ b/activesupport/lib/active_support/core_ext/uri.rb
@@ -1,22 +1,18 @@
 # encoding: utf-8
 
-if RUBY_VERSION >= '1.9'
-  require 'uri'
+require 'uri'
+str = "\xE6\x97\xA5\xE6\x9C\xAC\xE8\xAA\x9E" # Ni-ho-nn-go in UTF-8, means Japanese.
+parser = URI::Parser.new
 
-  str = "\xE6\x97\xA5\xE6\x9C\xAC\xE8\xAA\x9E" # Ni-ho-nn-go in UTF-8, means Japanese.
-
-  parser = URI::Parser.new
-
-  unless str == parser.unescape(parser.escape(str))
-    URI::Parser.class_eval do
-      remove_method :unescape
-      def unescape(str, escaped = /%[a-fA-F\d]{2}/)
-        # TODO: Are we actually sure that ASCII == UTF-8?
-        # YK: My initial experiments say yes, but let's be sure please
-        enc = str.encoding
-        enc = Encoding::UTF_8 if enc == Encoding::US_ASCII
-        str.gsub(escaped) { [$&[1, 2].hex].pack('C') }.force_encoding(enc)
-      end
+unless str == parser.unescape(parser.escape(str))
+  URI::Parser.class_eval do
+    remove_method :unescape
+    def unescape(str, escaped = /%[a-fA-F\d]{2}/)
+      # TODO: Are we actually sure that ASCII == UTF-8?
+      # YK: My initial experiments say yes, but let's be sure please
+      enc = str.encoding
+      enc = Encoding::UTF_8 if enc == Encoding::US_ASCII
+      str.gsub(escaped) { [$&[1, 2].hex].pack('C') }.force_encoding(enc)
     end
   end
 end
diff --git a/activesupport/lib/active_support/multibyte/chars.rb b/activesupport/lib/active_support/multibyte/chars.rb
index b78d92f599..ba35b515f2 100644
--- a/activesupport/lib/active_support/multibyte/chars.rb
+++ b/activesupport/lib/active_support/multibyte/chars.rb
@@ -38,16 +38,10 @@ module ActiveSupport #:nodoc:
       alias to_s wrapped_string
       alias to_str wrapped_string
 
-      if RUBY_VERSION >= "1.9"
-        # Creates a new Chars instance by wrapping _string_.
-        def initialize(string)
-          @wrapped_string = string
-          @wrapped_string.force_encoding(Encoding::UTF_8) unless @wrapped_string.frozen?
-        end
-      else
-        def initialize(string) #:nodoc:
-          @wrapped_string = string
-        end
+      # Creates a new Chars instance by wrapping _string_.
+      def initialize(string)
+        @wrapped_string = string
+        @wrapped_string.force_encoding(Encoding::UTF_8) unless @wrapped_string.frozen?
       end
 
       # Forward all undefined methods to the wrapped string.
@@ -94,151 +88,8 @@ module ActiveSupport #:nodoc:
         @wrapped_string <=> other.to_s
       end
 
-      if RUBY_VERSION < "1.9"
-        # Returns +true+ if the Chars class can and should act as a proxy for the string _string_. Returns
-        # +false+ otherwise.
-        def self.wants?(string)
-          $KCODE == 'UTF8' && consumes?(string)
-        end
-
-        # Returns a new Chars object containing the _other_ object concatenated to the string.
-        #
-        # Example:
-        #   ('Café'.mb_chars + ' périferôl').to_s # => "Café périferôl"
-        def +(other)
-          chars(@wrapped_string + other)
-        end
-
-        # Like <tt>String#=~</tt> only it returns the character offset (in codepoints) instead of the byte offset.
-        #
-        # Example:
-        #   'Café périferôl'.mb_chars =~ /ô/ # => 12
-        def =~(other)
-          translate_offset(@wrapped_string =~ other)
-        end
-
-        # Inserts the passed string at specified codepoint offsets.
-        #
-        # Example:
-        #   'Café'.mb_chars.insert(4, ' périferôl').to_s # => "Café périferôl"
-        def insert(offset, fragment)
-          unpacked = Unicode.u_unpack(@wrapped_string)
-          unless offset > unpacked.length
-            @wrapped_string.replace(
-              Unicode.u_unpack(@wrapped_string).insert(offset, *Unicode.u_unpack(fragment)).pack('U*')
-            )
-          else
-            raise IndexError, "index #{offset} out of string"
-          end
-          self
-        end
-
-        # Returns +true+ if contained string contains _other_. Returns +false+ otherwise.
-        #
-        # Example:
-        #   'Café'.mb_chars.include?('é') # => true
-        def include?(other)
-          # We have to redefine this method because Enumerable defines it.
-          @wrapped_string.include?(other)
-        end
-
-        # Returns the position _needle_ in the string, counting in codepoints. Returns +nil+ if _needle_ isn't found.
-        #
-        # Example:
-        #   'Café périferôl'.mb_chars.index('ô')   # => 12
-        #   'Café périferôl'.mb_chars.index(/\w/u) # => 0
-        def index(needle, offset=0)
-          wrapped_offset = first(offset).wrapped_string.length
-          index = @wrapped_string.index(needle, wrapped_offset)
-          index ? (Unicode.u_unpack(@wrapped_string.slice(0...index)).size) : nil
-        end
-
-        # Returns the position _needle_ in the string, counting in
-        # codepoints, searching backward from _offset_ or the end of the
-        # string. Returns +nil+ if _needle_ isn't found.
-        #
-        # Example:
-        #   'Café périferôl'.mb_chars.rindex('é')   # => 6
-        #   'Café périferôl'.mb_chars.rindex(/\w/u) # => 13
-        def rindex(needle, offset=nil)
-          offset ||= length
-          wrapped_offset = first(offset).wrapped_string.length
-          index = @wrapped_string.rindex(needle, wrapped_offset)
-          index ? (Unicode.u_unpack(@wrapped_string.slice(0...index)).size) : nil
-        end
-
-        # Returns the number of codepoints in the string
-        def size
-          Unicode.u_unpack(@wrapped_string).size
-        end
-        alias_method :length, :size
-
-        # Strips entire range of Unicode whitespace from the right of the string.
-        def rstrip
-          chars(@wrapped_string.gsub(Unicode::TRAILERS_PAT, ''))
-        end
-
-        # Strips entire range of Unicode whitespace from the left of the string.
-        def lstrip
-          chars(@wrapped_string.gsub(Unicode::LEADERS_PAT, ''))
-        end
-
-        # Strips entire range of Unicode whitespace from the right and left of the string.
-        def strip
-          rstrip.lstrip
-        end
-
-        # Returns the codepoint of the first character in the string.
-        #
-        # Example:
-        #   'こんにちは'.mb_chars.ord # => 12371
-        def ord
-          Unicode.u_unpack(@wrapped_string)[0]
-        end
-
-        # Works just like <tt>String#rjust</tt>, only integer specifies characters instead of bytes.
-        #
-        # Example:
-        #
-        #   "¾ cup".mb_chars.rjust(8).to_s
-        #   # => "   ¾ cup"
-        #
-        #   "¾ cup".mb_chars.rjust(8, " ").to_s # Use non-breaking whitespace
-        #   # => "   ¾ cup"
-        def rjust(integer, padstr=' ')
-          justify(integer, :right, padstr)
-        end
-
-        # Works just like <tt>String#ljust</tt>, only integer specifies characters instead of bytes.
-        #
-        # Example:
-        #
-        #   "¾ cup".mb_chars.rjust(8).to_s
-        #   # => "¾ cup   "
-        #
-        #   "¾ cup".mb_chars.rjust(8, " ").to_s # Use non-breaking whitespace
-        #   # => "¾ cup   "
-        def ljust(integer, padstr=' ')
-          justify(integer, :left, padstr)
-        end
-
-        # Works just like <tt>String#center</tt>, only integer specifies characters instead of bytes.
-        #
-        # Example:
-        #
-        #   "¾ cup".mb_chars.center(8).to_s
-        #   # => " ¾ cup  "
-        #
-        #   "¾ cup".mb_chars.center(8, " ").to_s # Use non-breaking whitespace
-        #   # => " ¾ cup  "
-        def center(integer, padstr=' ')
-          justify(integer, :center, padstr)
-        end
-
-      else
-        def =~(other)
-          @wrapped_string =~ other
-        end
+      def =~(other)
+        @wrapped_string =~ other
       end
 
       # Works just like <tt>String#split</tt>, with the exception that the items in the resulting list are Chars
diff --git a/activesupport/lib/active_support/ordered_hash.rb b/activesupport/lib/active_support/ordered_hash.rb
index b0d4f2bd86..d4f309fbd7 100644
--- a/activesupport/lib/active_support/ordered_hash.rb
+++ b/activesupport/lib/active_support/ordered_hash.rb
@@ -51,172 +51,5 @@ module ActiveSupport
     def extractable_options?
       true
     end
-
-    # Hash is ordered in Ruby 1.9!
-    if RUBY_VERSION < '1.9'
-
-      # In MRI the Hash class is core and written in C. In particular, methods are
-      # programmed with explicit C function calls and polymorphism is not honored.
-      #
-      # For example, []= is crucial in this implementation to maintain the @keys
-      # array but hash.c invokes rb_hash_aset() originally. This prevents method
-      # reuse through inheritance and forces us to reimplement stuff.
-      #
-      # For instance, we cannot use the inherited #merge! because albeit the algorithm
-      # itself would work, our []= is not being called at all by the C code.
-
-      def initialize(*args, &block)
-        super
-        @keys = []
-      end
-
-      def self.[](*args)
-        ordered_hash = new
-
-        if (args.length == 1 && args.first.is_a?(Array))
-          args.first.each do |key_value_pair|
-            next unless (key_value_pair.is_a?(Array))
-            ordered_hash[key_value_pair[0]] = key_value_pair[1]
-          end
-
-          return ordered_hash
-        end
-
-        unless (args.size % 2 == 0)
-          raise ArgumentError.new("odd number of arguments for Hash")
-        end
-
-        args.each_with_index do |val, ind|
-          next if (ind % 2 != 0)
-          ordered_hash[val] = args[ind + 1]
-        end
-
-        ordered_hash
-      end
-
-      def initialize_copy(other)
-        super
-        # make a deep copy of keys
-        @keys = other.keys
-      end
-
-      def []=(key, value)
-        @keys << key unless has_key?(key)
-        super
-      end
-
-      def delete(key)
-        if has_key? key
-          index = @keys.index(key)
-          @keys.delete_at index
-        end
-        super
-      end
-
-      def delete_if
-        super
-        sync_keys!
-        self
-      end
-
-      def reject!
-        super
-        sync_keys!
-        self
-      end
-
-      def reject(&block)
-        dup.reject!(&block)
-      end
-
-      def keys
-        @keys.dup
-      end
-
-      def values
-        @keys.collect { |key| self[key] }
-      end
-
-      def to_hash
-        self
-      end
-
-      def to_a
-        @keys.map { |key| [ key, self[key] ] }
-      end
-
-      def each_key
-        return to_enum(:each_key) unless block_given?
-        @keys.each { |key| yield key }
-        self
-      end
-
-      def each_value
-        return to_enum(:each_value) unless block_given?
-        @keys.each { |key| yield self[key]}
-        self
-      end
-
-      def each
-        return to_enum(:each) unless block_given?
-        @keys.each {|key| yield [key, self[key]]}
-        self
-      end
-
-      def each_pair
-        return to_enum(:each_pair) unless block_given?
-        @keys.each {|key| yield key, self[key]}
-        self
-      end
-
-      alias_method :select, :find_all
-
-      def clear
-        super
-        @keys.clear
-        self
-      end
-
-      def shift
-        k = @keys.first
-        v = delete(k)
-        [k, v]
-      end
-
-      def merge!(other_hash)
-        if block_given?
-          other_hash.each { |k, v| self[k] = key?(k) ? yield(k, self[k], v) : v }
-        else
-          other_hash.each { |k, v| self[k] = v }
-        end
-        self
-      end
-
-      alias_method :update, :merge!
-
-      def merge(other_hash, &block)
-        dup.merge!(other_hash, &block)
-      end
-
-      # When replacing with another hash, the initial order of our keys must come from the other hash -ordered or not.
-      def replace(other)
-        super
-        @keys = other.keys
-        self
-      end
-
-      def invert
-        OrderedHash[self.to_a.map!{|key_value_pair| key_value_pair.reverse}]
-      end
-
-      def inspect
-        "#<OrderedHash #{super}>"
-      end
-
-      private
-        def sync_keys!
-          @keys.delete_if {|k| !has_key?(k)}
-        end
-    end
   end
 end
diff --git a/activesupport/lib/active_support/testing/performance/ruby.rb b/activesupport/lib/active_support/testing/performance/ruby.rb
index 7d6d047ef6..26731c6bd7 100644
--- a/activesupport/lib/active_support/testing/performance/ruby.rb
+++ b/activesupport/lib/active_support/testing/performance/ruby.rb
@@ -144,8 +144,6 @@ end
 
 if RUBY_VERSION.between?('1.9.2', '2.0')
   require 'active_support/testing/performance/ruby/yarv'
-elsif RUBY_VERSION.between?('1.8.6', '1.9')
-  require 'active_support/testing/performance/ruby/mri'
 else
   $stderr.puts 'Update your ruby interpreter to be able to run benchmarks.'
   exit
diff --git a/activesupport/lib/active_support/testing/performance/ruby/mri.rb b/activesupport/lib/active_support/testing/performance/ruby/mri.rb
deleted file mode 100644
index 142279dd6e..0000000000
--- a/activesupport/lib/active_support/testing/performance/ruby/mri.rb
+++ /dev/null
@@ -1,57 +0,0 @@
-module ActiveSupport
-  module Testing
-    module Performance
-      module Metrics
-        class Base
-          protected
-            # Ruby 1.8 + ruby-prof wrapper (enable/disable stats for Benchmarker)
-            if GC.respond_to?(:enable_stats)
-              def with_gc_stats
-                GC.enable_stats
-                GC.start
-                yield
-              ensure
-                GC.disable_stats
-              end
-            end
-        end
-
-        class Memory < DigitalInformationUnit
-          # Ruby 1.8 + ruby-prof wrapper
-          if RubyProf.respond_to?(:measure_memory)
-            def measure
-              RubyProf.measure_memory
-            end
-          end
-        end
-
-        class Objects < Amount
-          # Ruby 1.8 + ruby-prof wrapper
-          if RubyProf.respond_to?(:measure_allocations)
-            def measure
-              RubyProf.measure_allocations
-            end
-          end
-        end
-
-        class GcRuns < Amount
-          # Ruby 1.8 + ruby-prof wrapper
-          if RubyProf.respond_to?(:measure_gc_runs)
-            def measure
-              RubyProf.measure_gc_runs
-            end
-          end
-        end
-
-        class GcTime < Time
-          # Ruby 1.8 + ruby-prof wrapper
-          if RubyProf.respond_to?(:measure_gc_time)
-            def measure
-              RubyProf.measure_gc_time / 1000.0 / 1000.0
-            end
-          end
-        end
-      end
-    end
-  end
-end
diff --git a/activesupport/test/abstract_unit.rb b/activesupport/test/abstract_unit.rb
index 0382739871..504ac3e9b9 100644
--- a/activesupport/test/abstract_unit.rb
+++ b/activesupport/test/abstract_unit.rb
@@ -11,15 +11,11 @@ lib = File.expand_path("#{File.dirname(__FILE__)}/../lib")
 $:.unshift(lib) unless $:.include?('lib') || $:.include?(lib)
 
 require 'active_support/core_ext/kernel/reporting'
-
 require 'active_support/core_ext/string/encoding'
-if "ruby".encoding_aware?
-  # These are the normal settings that will be set up by Railties
-  # TODO: Have these tests support other combinations of these values
-  silence_warnings do
-    Encoding.default_internal = "UTF-8"
-    Encoding.default_external = "UTF-8"
-  end
+
+silence_warnings do
+  Encoding.default_internal = "UTF-8"
+  Encoding.default_external = "UTF-8"
 end
 
 require 'test/unit'
@@ -30,9 +26,6 @@ silence_warnings { require 'mocha' }
 ENV['NO_RELOAD'] = '1'
 require 'active_support'
 
-# Include shims until we get off 1.8.6
-require 'active_support/ruby/shim' if RUBY_VERSION < '1.8.7'
-
 def uses_memcached(test_name)
   require 'memcache'
   begin
@@ -43,22 +36,5 @@ def uses_memcached(test_name)
   end
 end
 
-def with_kcode(code)
-  if RUBY_VERSION < '1.9'
-    begin
-      old_kcode, $KCODE = $KCODE, code
-      yield
-    ensure
-      $KCODE = old_kcode
-    end
-  else
-    yield
-  end
-end
-
 # Show backtraces for deprecated behavior for quicker cleanup.
-ActiveSupport::Deprecation.debug = true
-
-if RUBY_VERSION < '1.9'
-  $KCODE = 'UTF8'
-end
+ActiveSupport::Deprecation.debug = true
\ No newline at end of file
diff --git a/activesupport/test/core_ext/date_ext_test.rb b/activesupport/test/core_ext/date_ext_test.rb
index c040d86327..09d4765390 100644
--- a/activesupport/test/core_ext/date_ext_test.rb
+++ b/activesupport/test/core_ext/date_ext_test.rb
@@ -384,16 +384,6 @@ class DateExtCalculationsTest < ActiveSupport::TestCase
     end
   end
 
-  if RUBY_VERSION < '1.9'
-    def test_rfc3339
-      assert_equal('1980-02-28', Date.new(1980, 2, 28).rfc3339)
-    end
-
-    def test_iso8601
-      assert_equal('1980-02-28', Date.new(1980, 2, 28).iso8601)
-    end
-  end
-
   def test_today
     Date.stubs(:current).returns(Date.new(2000, 1, 1))
     assert_equal false, Date.new(1999, 12, 31).today?
diff --git a/activesupport/test/core_ext/hash_ext_test.rb b/activesupport/test/core_ext/hash_ext_test.rb
index eb8ed761da..dfa0cdb478 100644
--- a/activesupport/test/core_ext/hash_ext_test.rb
+++ b/activesupport/test/core_ext/hash_ext_test.rb
@@ -27,11 +27,7 @@ class HashExtTest < Test::Unit::TestCase
     @symbols = { :a  => 1, :b  => 2 }
     @mixed   = { :a  => 1, 'b' => 2 }
     @fixnums = {  0  => 1,  1  => 2 }
-    if RUBY_VERSION < '1.9.0'
-      @illegal_symbols = { "\0" => 1, "" => 2, [] => 3 }
-    else
-      @illegal_symbols = { [] => 3 }
-    end
+    @illegal_symbols = { [] => 3 }
   end
 
   def test_methods
diff --git a/activesupport/test/core_ext/range_ext_test.rb b/activesupport/test/core_ext/range_ext_test.rb
index 1424fa4aca..f4b773e5fb 100644
--- a/activesupport/test/core_ext/range_ext_test.rb
+++ b/activesupport/test/core_ext/range_ext_test.rb
@@ -63,15 +63,8 @@ class RangeTest < Test::Unit::TestCase
     assert_equal [1,3,5,7,9], array
   end
 
-  if RUBY_VERSION < '1.9'
-    def test_cover
-      assert((1..3).cover?(2))
-      assert !(1..3).cover?(4)
-    end
-  else
-    def test_cover_is_not_override
-      range = (1..3)
-      assert range.method(:include?) != range.method(:cover?)
-    end
+  def test_cover_is_not_override
+    range = (1..3)
+    assert range.method(:include?) != range.method(:cover?)
   end
 end
diff --git a/activesupport/test/core_ext/string_ext_test.rb b/activesupport/test/core_ext/string_ext_test.rb
index 47b9f68ed0..aeae2579b4 100644
--- a/activesupport/test/core_ext/string_ext_test.rb
+++ b/activesupport/test/core_ext/string_ext_test.rb
@@ -160,14 +160,6 @@ class StringInflectionsTest < Test::Unit::TestCase
     assert_equal 97, 'abc'.ord
   end
 
-  if RUBY_VERSION < '1.9'
-    def test_getbyte
-      assert_equal 97, 'a'.getbyte(0)
-      assert_equal 99, 'abc'.getbyte(2)
-      assert_nil   'abc'.getbyte(3)
-    end
-  end
-
   def test_string_to_time
     assert_equal Time.utc(2005, 2, 27, 23, 50), "2005-02-27 23:50".to_time
     assert_equal Time.local(2005, 2, 27, 23, 50), "2005-02-27 23:50".to_time(:local)
@@ -287,21 +279,9 @@ class StringInflectionsTest < Test::Unit::TestCase
     assert_equal "Hello Big[...]", "Hello Big World!".truncate(15, :omission => "[...]", :separator => ' ')
   end
 
-  if RUBY_VERSION < '1.9.0'
-    def test_truncate_multibyte
-      with_kcode 'none' do
-        assert_equal "\354\225\210\353\205\225\355...", "\354\225\210\353\205\225\355\225\230\354\204\270\354\232\224".truncate(10)
-      end
-      with_kcode 'u' do
-        assert_equal "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 ...",
-          "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 \354\225\204\353\235\274\353\246\254\354\230\244".truncate(10)
-      end
-    end
-  else
-    def test_truncate_multibyte
-      assert_equal "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 ...".force_encoding('UTF-8'),
-        "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 \354\225\204\353\235\274\353\246\254\354\230\244".force_encoding('UTF-8').truncate(10)
-    end
+  def test_truncate_multibyte
+    assert_equal "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 ...".force_encoding('UTF-8'),
+      "\354\225\204\353\246\254\353\236\221 \354\225\204\353\246\254 \354\225\204\353\235\274\353\246\254\354\230\244".force_encoding('UTF-8').truncate(10)
   end
 
   def test_constantize
@@ -338,22 +318,8 @@ class CoreExtStringMultibyteTest < ActiveSupport::TestCase
     assert !BYTE_STRING.is_utf8?
   end
 
-  if RUBY_VERSION < '1.9'
-    def test_mb_chars_returns_self_when_kcode_not_set
-      with_kcode('none') do
-        assert_kind_of String, UNICODE_STRING.mb_chars
-      end
-    end
-
-    def test_mb_chars_returns_an_instance_of_the_chars_proxy_when_kcode_utf8
-      with_kcode('UTF8') do
-        assert_kind_of ActiveSupport::Multibyte.proxy_class, UNICODE_STRING.mb_chars
-      end
-    end
-  else
-    def test_mb_chars_returns_instance_of_proxy_class
-      assert_kind_of ActiveSupport::Multibyte.proxy_class, UNICODE_STRING.mb_chars
-    end
+  def test_mb_chars_returns_instance_of_proxy_class
+    assert_kind_of ActiveSupport::Multibyte.proxy_class, UNICODE_STRING.mb_chars
   end
 end
 
@@ -479,11 +445,7 @@ class OutputSafetyTest < ActiveSupport::TestCase
   end
 
   test 'knows whether it is encoding aware' do
-    if RUBY_VERSION >= "1.9"
-      assert 'ruby'.encoding_aware?
-    else
-      assert !'ruby'.encoding_aware?
-    end
+    assert 'ruby'.encoding_aware?
   end
 
   test "call to_param returns a normal string" do
diff --git a/activesupport/test/core_ext/time_with_zone_test.rb b/activesupport/test/core_ext/time_with_zone_test.rb
index 9d9e411c28..04f5ea85a8 100644
--- a/activesupport/test/core_ext/time_with_zone_test.rb
+++ b/activesupport/test/core_ext/time_with_zone_test.rb
@@ -448,9 +448,8 @@ class TimeWithZoneTest < Test::Unit::TestCase
   end
 
   def test_ruby_19_weekday_name_query_methods
-    ruby_19_or_greater = RUBY_VERSION >= '1.9'
     %w(sunday? monday? tuesday? wednesday? thursday? friday? saturday?).each do |name|
-      assert_equal ruby_19_or_greater, @twz.respond_to?(name)
+      assert_respond_to @twz, name
     end
   end
 
diff --git a/activesupport/test/json/encoding_test.rb b/activesupport/test/json/encoding_test.rb
index 8cf1a54a99..ad9a497515 100644
--- a/activesupport/test/json/encoding_test.rb
+++ b/activesupport/test/json/encoding_test.rb
@@ -88,25 +88,21 @@ class TestJSONEncoding < Test::Unit::TestCase
     assert_equal %({\"a\":\"b\",\"c\":\"d\"}), sorted_json(ActiveSupport::JSON.encode(:a => :b, :c => :d))
   end
 
-  def test_utf8_string_encoded_properly_when_kcode_is_utf8
-    with_kcode 'UTF8' do
-      result = ActiveSupport::JSON.encode('€2.99')
-      assert_equal '"\\u20ac2.99"', result
-      assert_equal(Encoding::UTF_8, result.encoding) if result.respond_to?(:encoding)
-
-      result = ActiveSupport::JSON.encode('✎☺')
-      assert_equal '"\\u270e\\u263a"', result
-      assert_equal(Encoding::UTF_8, result.encoding) if result.respond_to?(:encoding)
-    end
+  def test_utf8_string_encoded_properly
+    result = ActiveSupport::JSON.encode('€2.99')
+    assert_equal '"\\u20ac2.99"', result
+    assert_equal(Encoding::UTF_8, result.encoding) if result.respond_to?(:encoding)
+
+    result = ActiveSupport::JSON.encode('✎☺')
+    assert_equal '"\\u270e\\u263a"', result
+    assert_equal(Encoding::UTF_8, result.encoding) if result.respond_to?(:encoding)
   end
 
-  if '1.9'.respond_to?(:force_encoding)
-    def test_non_utf8_string_transcodes
-      s = '二'.encode('Shift_JIS')
-      result = ActiveSupport::JSON.encode(s)
-      assert_equal '"\\u4e8c"', result
-      assert_equal Encoding::UTF_8, result.encoding
-    end
+  def test_non_utf8_string_transcodes
+    s = '二'.encode('Shift_JIS')
+    result = ActiveSupport::JSON.encode(s)
+    assert_equal '"\\u4e8c"', result
+    assert_equal Encoding::UTF_8, result.encoding
   end
 
   def test_exception_raised_when_encoding_circular_reference_in_array
diff --git a/activesupport/test/multibyte_chars_test.rb b/activesupport/test/multibyte_chars_test.rb
index bfff10fff2..ba04638354 100644
--- a/activesupport/test/multibyte_chars_test.rb
+++ b/activesupport/test/multibyte_chars_test.rb
@@ -101,15 +101,8 @@ class MultibyteCharsUTF8BehaviourTest < Test::Unit::TestCase
 
   def setup
     @chars = UNICODE_STRING.dup.mb_chars
-
-    if RUBY_VERSION < '1.9'
-      # Multibyte support all kinds of whitespace (ie. NEWLINE, SPACE, EM SPACE)
-      @whitespace = "\n\t#{[32, 8195].pack('U*')}"
-    else
-      # Ruby 1.9 only supports basic whitespace
-      @whitespace = "\n\t "
-    end
-
+    # Ruby 1.9 only supports basic whitespace
+    @whitespace = "\n\t "
     @byte_order_mark = [65279].pack('U')
   end
 
diff --git a/activesupport/test/multibyte_utils_test.rb b/activesupport/test/multibyte_utils_test.rb
index 0a2f20d282..9a8f7050fe 100644
--- a/activesupport/test/multibyte_utils_test.rb
+++ b/activesupport/test/multibyte_utils_test.rb
@@ -56,37 +56,9 @@ class MultibyteUtilsTest < ActiveSupport::TestCase
     end
   end
 
-  if RUBY_VERSION < '1.9'
-    test "clean leaves ASCII strings intact" do
-      with_encoding('None') do
-        [
-          'word', "\270\236\010\210\245"
-        ].each do |string|
-          assert_equal string, ActiveSupport::Multibyte.clean(string)
-        end
-      end
-    end
-
-    test "clean cleans invalid characters from UTF-8 encoded strings" do
-      with_encoding('UTF8') do
-        cleaned_utf8 = [8].pack('C*')
-        assert_equal example('valid UTF-8'), ActiveSupport::Multibyte.clean(example('valid UTF-8'))
-        assert_equal cleaned_utf8, ActiveSupport::Multibyte.clean(example('invalid UTF-8'))
-      end
-    end
-
-    test "clean cleans invalid characters from Shift-JIS encoded strings" do
-      with_encoding('SJIS') do
-        cleaned_sjis = [184, 0, 136, 165].pack('C*')
-        assert_equal example('valid Shift-JIS'), ActiveSupport::Multibyte.clean(example('valid Shift-JIS'))
-        assert_equal cleaned_sjis, ActiveSupport::Multibyte.clean(example('invalid Shift-JIS'))
-      end
-    end
-  else
-    test "clean is a no-op" do
-      with_encoding('UTF8') do
-        assert_equal example('invalid Shift-JIS'), ActiveSupport::Multibyte.clean(example('invalid Shift-JIS'))
-      end
+  test "clean is a no-op" do
+    with_encoding('UTF8') do
+      assert_equal example('invalid Shift-JIS'), ActiveSupport::Multibyte.clean(example('invalid Shift-JIS'))
     end
   end
 
@@ -119,19 +91,13 @@ class MultibyteUtilsTest < ActiveSupport::TestCase
     end
   end
 
-  if 'string'.respond_to?(:encoding)
-    KCODE_TO_ENCODING = Hash.new(Encoding::BINARY).
-      update('UTF8' => Encoding::UTF_8, 'SJIS' => Encoding::Shift_JIS)
-
-    def with_encoding(enc)
-      before = Encoding.default_external
-      silence_warnings { Encoding.default_external = KCODE_TO_ENCODING[enc] }
+  KCODE_TO_ENCODING = Hash.new(Encoding::BINARY).
+    update('UTF8' => Encoding::UTF_8, 'SJIS' => Encoding::Shift_JIS)
 
-      yield
-
-      silence_warnings { Encoding.default_external = before }
-    end
-  else
-    alias with_encoding with_kcode
+  def with_encoding(enc)
+    before = Encoding.default_external
+    silence_warnings { Encoding.default_external = KCODE_TO_ENCODING[enc] }
+    yield
+    silence_warnings { Encoding.default_external = before }
   end
 end
diff --git a/activesupport/test/ordered_hash_test.rb b/activesupport/test/ordered_hash_test.rb
index 0b5f912dc4..8119b36491 100644
--- a/activesupport/test/ordered_hash_test.rb
+++ b/activesupport/test/ordered_hash_test.rb
@@ -81,24 +81,21 @@ class OrderedHashTest < Test::Unit::TestCase
     keys = []
     assert_equal @ordered_hash, @ordered_hash.each_key { |k| keys << k }
     assert_equal @keys, keys
-    expected_class = RUBY_VERSION < '1.9' ? Enumerable::Enumerator : Enumerator
-    assert_kind_of expected_class, @ordered_hash.each_key
+    assert_kind_of Enumerator, @ordered_hash.each_key
   end
 
   def test_each_value
     values = []
     assert_equal @ordered_hash, @ordered_hash.each_value { |v| values << v }
     assert_equal @values, values
-    expected_class = RUBY_VERSION < '1.9' ? Enumerable::Enumerator : Enumerator
-    assert_kind_of expected_class, @ordered_hash.each_value
+    assert_kind_of Enumerator, @ordered_hash.each_value
   end
 
   def test_each
     values = []
     assert_equal @ordered_hash, @ordered_hash.each {|key, value| values << value}
     assert_equal @values, values
-    expected_class = RUBY_VERSION < '1.9' ? Enumerable::Enumerator : Enumerator
-    assert_kind_of expected_class, @ordered_hash.each
+    assert_kind_of Enumerator, @ordered_hash.each
   end
 
   def test_each_with_index
@@ -114,9 +111,7 @@ class OrderedHashTest < Test::Unit::TestCase
     end
     assert_equal @values, values
     assert_equal @keys, keys
-
-    expected_class = RUBY_VERSION < '1.9' ? Enumerable::Enumerator : Enumerator
-    assert_kind_of expected_class, @ordered_hash.each_pair
+    assert_kind_of Enumerator, @ordered_hash.each_pair
   end
 
   def test_find_all