From 5239346afe9207849b45a02d1293f6805aa7faec Mon Sep 17 00:00:00 2001
From: Colin Kelley <ColinKelley@ColinKelley.local>
Date: Sat, 26 Dec 2009 16:06:19 -0800
Subject: [PATCH] Added Object#nonblank? (analogous to Numeric#nonzero?)

---
 .../lib/active_support/core_ext/object/blank.rb    |   27 ++++++++++++++++++++
 activesupport/test/core_ext/blank_test.rb          |    5 +++
 2 files changed, 32 insertions(+), 0 deletions(-)

diff --git a/activesupport/lib/active_support/core_ext/object/blank.rb b/activesupport/lib/active_support/core_ext/object/blank.rb
index 9a1f663..bd5e8a4 100644
--- a/activesupport/lib/active_support/core_ext/object/blank.rb
+++ b/activesupport/lib/active_support/core_ext/object/blank.rb
@@ -17,6 +17,33 @@ class Object
   def present?
     !blank?
   end
+
+  # The nonblank? method is analogous to Ruby's Numeric#nonzero?[http://ruby-doc.org/core/classes/Numeric.html#M000186] method.
+  #
+  # Returns object unless it's #blank?(), in which case it returns nil:
+  # object.nonblank? is equivalent to (object.blank? : nil : object).
+  #
+  # This is handy for any representation of objects where blank is the same
+  # as not present at all.  For example, this simplifies a common check for
+  # HTTP POST/query parameters:
+  #
+  #   state   = params[:state]   unless params[:state].blank?
+  #   country = params[:country] unless params[:country].blank?
+  #   region  = state || country || 'US'
+  #
+  # becomes
+  #
+  #   region = params[:state].nonblank? || params[:country].nonblank? || 'US'
+  #
+  # In general, nonblank? can be used any time you want to map empty? or false
+  # to nil:
+  #
+  #   options = { :html => { :style => 'margin: 10;' } }
+  #   other_options = options.except(:html).nonblank?
+  #   => nil
+  def nonblank?
+    self unless blank?
+  end
 end
 
 class NilClass #:nodoc:
diff --git a/activesupport/test/core_ext/blank_test.rb b/activesupport/test/core_ext/blank_test.rb
index 1dbbf3f..d40dc77 100644
--- a/activesupport/test/core_ext/blank_test.rb
+++ b/activesupport/test/core_ext/blank_test.rb
@@ -22,4 +22,9 @@ class BlankTest < Test::Unit::TestCase
     BLANK.each { |v| assert !v.present?, "#{v.inspect} should not be present" }
     NOT.each   { |v| assert v.present?, "#{v.inspect} should be present" }
   end
+
+  def test_nonblank
+    BLANK.each { |v| assert_equal nil, v.nonblank?, "#{v.inspect}.nonblank? should return nil" }
+    NOT.each   { |v| assert_equal v,   v.nonblank?, "#{v.inspect}.nonblank? should return self" }
+  end
 end
-- 
1.6.4.1