Ticket #7369: hash-without.diff

activesupport/lib/active_support/core_ext/hash/slice.rb

@@ -11 +11 @@
-      #   end
-      #
-      #   search(options.slice(:mass, :velocity, :time))
+      # 
+      # Also allows leaving out certain keys. This is useful when duplicating
+      # a hash but omitting a certain subset:
+      # 
+      #   Event.new(event.attributes.without(:id, :user_id))
-      module Slice
-        # Returns a new hash with only the given keys.
-        def slice(*keys)
@@ -22 +27 @@
-        def slice!(*keys)
-          replace(slice(*keys))
-        end
+
+        # Returns a new hash without the given keys.
+        def without(*keys)
+          allowed = self.keys - (respond_to?(:convert_key) ? keys.map { |key| convert_key(key) } : keys)
+          slice(*allowed)
+        end
+        
+        # Replaces the hash without the given keys.
+        def without!(*keys)
+          replace(without(*keys))
+        end
-      end
-    end
-  end

activesupport/test/core_ext/hash_ext_test.rb

@@ -272 +272 @@
-      assert_equal expected, copy
-    end
-  end
+  
+  def test_without
+    original = { :a => 'x', :b => 'y', :c => 10 }
+    expected = { :a => 'x' }
+    
+    # Should return a hash without the given keys.
+    assert_equal expected, original.without(:b, :c)
+    assert_not_equal expected, original
+    
+    # Should ignore non-existant keys.
+    assert_equal expected, original.without(:b, :c, :d)
+    
+    # Should replace the hash with the given keys taken away.
+    assert_equal expected, original.without!(:b, :c)
+    assert_equal expected, original
+  end
+
+  def test_indifferent_without
+    original = { :a => 'x', :b => 'y', :c => 10 }.with_indifferent_access
+    expected = { :c => 10 }.with_indifferent_access
+
+    [['a', 'b'], [:a, :b]].each do |keys|
+      # Should return a new hash without the given keys.
+      assert_equal expected, original.without(*keys), keys.inspect
+      assert_not_equal expected, original
+
+      # Should replace the hash without the given keys.
+      copy = original.dup
+      assert_equal expected, copy.without!(*keys)
+      assert_equal expected, copy
+    end
+  end
-end
-
-class IWriteMyOwnXML