Merge pull request #13 from kassio/master

Adds a blacklist of classes to be ignored

Author: JonRowe

lib/rspec/collection_matchers/have.rb

@@ -2,6 +2,7 @@ module RSpec
   module CollectionMatchers
     class Have
       QUERY_METHODS = [:size, :length, :count].freeze
+      IGNORED_CLASSES = [Integer].freeze
 
       def initialize(expected, relativity=:exactly)
         @expected = case expected
@@ -33,7 +34,7 @@ def matches?(collection_or_owner)
           raise not_a_collection if @actual.nil?
         else
           query_method = determine_query_method(collection)
-          raise not_a_collection unless query_method
+          raise not_a_collection if !query_method || is_ignored_class?(collection)
           @actual = collection.__send__(query_method)
         end
         case @relativity
@@ -60,6 +61,10 @@ def determine_query_method(collection)
         QUERY_METHODS.detect {|m| collection.respond_to?(m)}
       end
 
+      def is_ignored_class?(collection)
+        IGNORED_CLASSES.any? {|klass| klass === collection}
+      end
+
       def not_a_collection
         "expected #{@collection_name} to be a collection but it does not respond to #length, #size or #count"
       end

spec/rspec/collection_matchers/have_spec.rb

@@ -105,6 +105,17 @@ def create_collection_owner_with(n)
   end
 
   describe "expect(...).to have(n).items where result responds to items but returns something other than a collection" do
+    it "provides a meaningful error" do
+      owner = Class.new do
+        def items
+          1
+        end
+      end.new
+      expect do
+        expect(owner).to have(3).items
+      end.to raise_error("expected items to be a collection but it does not respond to #length, #size or #count")
+    end
+
     it "provides a meaningful error" do
       owner = Class.new do
         def items