added RSpec and RSpec on Rails

[rails.git] / vendor / gems / rspec-1.1.2 / lib / spec / matchers / change.rb

diff --git a/vendor/gems/rspec-1.1.2/lib/spec/matchers/change.rb b/vendor/gems/rspec-1.1.2/lib/spec/matchers/change.rb
new file mode 100644 (file)
index 0000000..784e516
--- /dev/null
+++ b/vendor/gems/rspec-1.1.2/lib/spec/matchers/change.rb
@@ -0,0 +1,144 @@
+module Spec
+  module Matchers
+    
+    #Based on patch from Wilson Bilkovich
+    class Change #:nodoc:
+      def initialize(receiver=nil, message=nil, &block)
+        @receiver = receiver
+        @message = message
+        @block = block
+      end
+      
+      def matches?(target, &block)
+        if block
+          raise MatcherError.new(<<-EOF
+block passed to should or should_not change must use {} instead of do/end
+EOF
+)
+        end
+        @target = target
+        execute_change
+        return false if @from && (@from != @before)
+        return false if @to && (@to != @after)
+        return (@before + @amount == @after) if @amount
+        return ((@after - @before) >= @minimum) if @minimum
+        return ((@after - @before) <= @maximum) if @maximum        
+        return @before != @after
+      end
+      
+      def execute_change
+        @before = @block.nil? ? @receiver.send(@message) : @block.call
+        @target.call
+        @after = @block.nil? ? @receiver.send(@message) : @block.call
+      end
+      
+      def failure_message
+        if @to
+          "#{result} should have been changed to #{@to.inspect}, but is now #{@after.inspect}"
+        elsif @from
+          "#{result} should have initially been #{@from.inspect}, but was #{@before.inspect}"
+        elsif @amount
+          "#{result} should have been changed by #{@amount.inspect}, but was changed by #{actual_delta.inspect}"
+        elsif @minimum
+          "#{result} should have been changed by at least #{@minimum.inspect}, but was changed by #{actual_delta.inspect}"
+        elsif @maximum
+          "#{result} should have been changed by at most #{@maximum.inspect}, but was changed by #{actual_delta.inspect}"
+        else
+          "#{result} should have changed, but is still #{@before.inspect}"
+        end
+      end
+      
+      def result
+        @message || "result"
+      end
+      
+      def actual_delta
+        @after - @before
+      end
+      
+      def negative_failure_message
+        "#{result} should not have changed, but did change from #{@before.inspect} to #{@after.inspect}"
+      end
+      
+      def by(amount)
+        @amount = amount
+        self
+      end
+      
+      def by_at_least(minimum)
+        @minimum = minimum
+        self
+      end
+      
+      def by_at_most(maximum)
+        @maximum = maximum
+        self
+      end      
+      
+      def to(to)
+        @to = to
+        self
+      end
+      
+      def from (from)
+        @from = from
+        self
+      end
+    end
+    
+    # :call-seq:
+    #   should change(receiver, message, &block)
+    #   should change(receiver, message, &block).by(value)
+    #   should change(receiver, message, &block).from(old).to(new)
+    #   should_not change(receiver, message, &block)
+    #
+    # Allows you to specify that a Proc will cause some value to change.
+    #
+    # == Examples
+    #
+    #   lambda {
+    #     team.add_player(player) 
+    #   }.should change(roster, :count)
+    #
+    #   lambda {
+    #     team.add_player(player) 
+    #   }.should change(roster, :count).by(1)
+    #
+    #   lambda {
+    #     team.add_player(player) 
+    #   }.should change(roster, :count).by_at_least(1)
+    #
+    #   lambda {
+    #     team.add_player(player)
+    #   }.should change(roster, :count).by_at_most(1)    
+    #
+    #   string = "string"
+    #   lambda {
+    #     string.reverse
+    #   }.should change { string }.from("string").to("gnirts")
+    #
+    #   lambda {
+    #     person.happy_birthday
+    #   }.should change(person, :birthday).from(32).to(33)
+    #       
+    #   lambda {
+    #     employee.develop_great_new_social_networking_app
+    #   }.should change(employee, :title).from("Mail Clerk").to("CEO")
+    #
+    # Evaluates +receiver.message+ or +block+ before and
+    # after it evaluates the c object (generated by the lambdas in the examples above).
+    #
+    # Then compares the values before and after the +receiver.message+ and
+    # evaluates the difference compared to the expected difference.
+    #
+    # == Warning
+    # +should_not+ +change+ only supports the form with no subsequent calls to
+    # +by+, +by_at_least+, +by_at_most+, +to+ or +from+.
+    #
+    # blocks passed to +should+ +change+ and +should_not+ +change+
+    # must use the <tt>{}</tt> form (<tt>do/end</tt> is not supported)
+    def change(target=nil, message=nil, &block)
+      Matchers::Change.new(target, message, &block)
+    end
+  end
+end