Drop runtime dependency on ActiveSupport due to minimum ruby requirement

more_core_extensions/core_ext/object/blank.rb was copied from
https://github.com/rails/rails/blob/v5.0.0/activesupport/lib/active_support/core_ext/object/blank.rb

With the release of ActiveSupport v5.0.0 a minimum required_ruby_version
of '>= 2.2.2' was added.  The code for Blank has been copied here so that
we can continue to support ruby versions that don't meet that requirement.

The test was mostly copied as well, but rewritten in rspec syntax.

ActiveSupport has been added as a development dependency for ruby >= 2.2.2
to allow for testing nested hash features with HashWithIndifferentAccess

lib/more_core_extensions/core_ext/array/deletes.rb

@@ -1,5 +1,4 @@
-require 'active_support'
-require 'active_support/core_ext/object/blank'
+require 'more_core_extensions/core_ext/object/blank'
 
 module MoreCoreExtensions
   module ArrayDeletes

lib/more_core_extensions/core_ext/hash/deletes.rb

@@ -1,5 +1,4 @@
-require 'active_support'
-require 'active_support/core_ext/object/blank'
+require 'more_core_extensions/core_ext/object/blank'
 
 module MoreCoreExtensions
   module HashDeletes

lib/more_core_extensions/core_ext/object.rb

@@ -1 +1,2 @@
+require 'more_core_extensions/core_ext/object/blank'
 require 'more_core_extensions/core_ext/object/namespace'

lib/more_core_extensions/core_ext/object/blank.rb

@@ -0,0 +1,149 @@
+# Copied from https://github.com/rails/rails/blob/v5.0.0/activesupport/lib/active_support/core_ext/object/blank.rb
+# With the release of ActiveSupport v5.0.0 a minimum required_ruby_version of '>= 2.2.2' was added.
+# This code has been copied here so that we can continue to support ruby versions that don't meet that requirement.
+
+unless Object.respond_to?(:blank?)
+  class Object
+    # An object is blank if it's false, empty, or a whitespace string.
+    # For example, +false+, '', '   ', +nil+, [], and {} are all blank.
+    #
+    # This simplifies
+    #
+    #   !address || address.empty?
+    #
+    # to
+    #
+    #   address.blank?
+    #
+    # @return [true, false]
+    def blank?
+      respond_to?(:empty?) ? !!empty? : !self
+    end
+
+    # An object is present if it's not blank.
+    #
+    # @return [true, false]
+    def present?
+      !blank?
+    end
+
+    # Returns the receiver if it's present otherwise returns +nil+.
+    # <tt>object.presence</tt> is equivalent to
+    #
+    #    object.present? ? object : nil
+    #
+    # For example, something like
+    #
+    #   state   = params[:state]   if params[:state].present?
+    #   country = params[:country] if params[:country].present?
+    #   region  = state || country || 'US'
+    #
+    # becomes
+    #
+    #   region = params[:state].presence || params[:country].presence || 'US'
+    #
+    # @return [Object]
+    def presence
+      self if present?
+    end
+  end
+
+  class NilClass
+    # +nil+ is blank:
+    #
+    #   nil.blank? # => true
+    #
+    # @return [true]
+    def blank?
+      true
+    end
+  end
+
+  class FalseClass
+    # +false+ is blank:
+    #
+    #   false.blank? # => true
+    #
+    # @return [true]
+    def blank?
+      true
+    end
+  end
+
+  class TrueClass
+    # +true+ is not blank:
+    #
+    #   true.blank? # => false
+    #
+    # @return [false]
+    def blank?
+      false
+    end
+  end
+
+  class Array
+    # An array is blank if it's empty:
+    #
+    #   [].blank?      # => true
+    #   [1,2,3].blank? # => false
+    #
+    # @return [true, false]
+    alias_method :blank?, :empty?
+  end
+
+  class Hash
+    # A hash is blank if it's empty:
+    #
+    #   {}.blank?                # => true
+    #   { key: 'value' }.blank?  # => false
+    #
+    # @return [true, false]
+    alias_method :blank?, :empty?
+  end
+
+  class String
+    BLANK_RE = /\A[[:space:]]*\z/
+
+    # A string is blank if it's empty or contains whitespaces only:
+    #
+    #   ''.blank?       # => true
+    #   '   '.blank?    # => true
+    #   "\t\n\r".blank? # => true
+    #   ' blah '.blank? # => false
+    #
+    # Unicode whitespace is supported:
+    #
+    #   "\u00a0".blank? # => true
+    #
+    # @return [true, false]
+    def blank?
+      # The regexp that matches blank strings is expensive. For the case of empty
+      # strings we can speed up this method (~3.5x) with an empty? call. The
+      # penalty for the rest of strings is marginal.
+      empty? || BLANK_RE === self
+    end
+  end
+
+  class Numeric #:nodoc:
+    # No number is blank:
+    #
+    #   1.blank? # => false
+    #   0.blank? # => false
+    #
+    # @return [false]
+    def blank?
+      false
+    end
+  end
+
+  class Time #:nodoc:
+    # No Time is blank:
+    #
+    #   Time.now.blank? # => false
+    #
+    # @return [false]
+    def blank?
+      false
+    end
+  end
+end

more_core_extensions.gemspec

@@ -22,10 +22,11 @@ Gem::Specification.new do |spec|
 
   spec.required_ruby_version = ">= 1.9.3"
 
+  if Gem::Version.new(RUBY_VERSION) >= Gem::Version.new("2.2.2")
+    spec.add_development_dependency 'activesupport'
+  end
   spec.add_development_dependency "bundler", "~> 1.3"
   spec.add_development_dependency "coveralls"
   spec.add_development_dependency "rake"
   spec.add_development_dependency "rspec", ">= 3.0"
-
-  spec.add_dependency "activesupport", "> 3.2"
 end

spec/core_ext/hash/nested_spec.rb

@@ -190,39 +190,43 @@
   include_examples "core_ext/hash/nested"
 end
 
-require 'active_support'
-require 'active_support/core_ext/hash'
-describe HashWithIndifferentAccess do
-  let(:hash) do
-    described_class.new.merge(
-      "a" => 1,
-      "b" => {},
-      "c" => {"c1" => 2},
-      "d" => {"d1" => {"d2" => {"d3" => 3}}},
-      "e" => Hash.new(4),
-      "f" => described_class.new { |h, k| h[k] = described_class.new },
-      nil => {nil => 7},
-      ["h", "i"] => 8
-    )
-
-    # NOTE: "f" has to be initialized in that way due to a bug in
-    #   HashWithIndifferentAccess and assigning a Hash with a default proc.
-    #
-    # 1.9.3 :001 > h1 = Hash.new
-    # 1.9.3 :002 > h1[:a] = Hash.new { |h, k| h[k] = Hash.new }
-    # 1.9.3 :003 > h1[:a].class
-    #  => Hash
-    # 1.9.3 :004 > h1[:a][:b].class
-    #  => Hash
-    #
-    # 1.9.3 :005 > require 'active_support/all'
-    # 1.9.3 :006 > h2 = HashWithIndifferentAccess.new
-    # 1.9.3 :007 > h2[:a] = Hash.new { |h, k| h[k] = Hash.new }
-    # 1.9.3 :008 > h2[:a].class
-    #  => ActiveSupport::HashWithIndifferentAccess
-    # 1.9.3 :009 > h2[:a][:b].class
-    #  => NilClass
+begin
+  require 'active_support'
+  require 'active_support/core_ext/hash'
+  describe HashWithIndifferentAccess do
+    let(:hash) do
+      described_class.new.merge(
+        "a" => 1,
+        "b" => {},
+        "c" => {"c1" => 2},
+        "d" => {"d1" => {"d2" => {"d3" => 3}}},
+        "e" => Hash.new(4),
+        "f" => described_class.new { |h, k| h[k] = described_class.new },
+        nil => {nil => 7},
+        ["h", "i"] => 8
+      )
+
+      # NOTE: "f" has to be initialized in that way due to a bug in
+      #   HashWithIndifferentAccess and assigning a Hash with a default proc.
+      #
+      # 1.9.3 :001 > h1 = Hash.new
+      # 1.9.3 :002 > h1[:a] = Hash.new { |h, k| h[k] = Hash.new }
+      # 1.9.3 :003 > h1[:a].class
+      #  => Hash
+      # 1.9.3 :004 > h1[:a][:b].class
+      #  => Hash
+      #
+      # 1.9.3 :005 > require 'active_support/all'
+      # 1.9.3 :006 > h2 = HashWithIndifferentAccess.new
+      # 1.9.3 :007 > h2[:a] = Hash.new { |h, k| h[k] = Hash.new }
+      # 1.9.3 :008 > h2[:a].class
+      #  => ActiveSupport::HashWithIndifferentAccess
+      # 1.9.3 :009 > h2[:a][:b].class
+      #  => NilClass
+    end
+
+    include_examples "core_ext/hash/nested"
   end
-
-  include_examples "core_ext/hash/nested"
+rescue LoadError
+  # ActiveSupport v5.0.0 requires ruby '>=2.2.2', skip these tests on older rubies.
 end

spec/core_ext/object/blank_spec.rb

@@ -0,0 +1,46 @@
+describe "blank" do
+  class EmptyTrue
+    def empty?
+      0
+    end
+  end
+
+  class EmptyFalse
+    def empty?
+      nil
+    end
+  end
+
+  BLANK   = [ EmptyTrue.new, nil, false, '', '   ', "  \n\t  \r ", '　', "\u00a0", [], {} ]
+  PRESENT = [ EmptyFalse.new, Object.new, true, 0, 1, 'a', [nil], { nil => 0 } ]
+
+  describe "#blank?" do
+    context "true" do
+      BLANK.each { |v| it("#{v.inspect}") { expect(v).to be_blank } }
+    end
+
+    context "false" do
+      PRESENT.each { |v| it("#{v.inspect}") { expect(v).to_not be_blank } }
+    end
+  end
+
+  describe "#present?" do
+    context "true" do
+      PRESENT.each { |v| it("#{v.inspect}") { expect(v).to be_present } }
+    end
+
+    context "false" do
+      BLANK.each { |v| it("#{v.inspect}") { expect(v).to_not be_present } }
+    end
+  end
+
+  describe "#presence" do
+    context "object" do
+      PRESENT.each { |v| it("#{v.inspect}") { expect(v.presence).to eq(v) } }
+    end
+
+    context "nil" do
+      BLANK.each { |v| it("#{v.inspect}") { expect(v.presence).to be_nil } }
+    end
+  end
+end