Make KeywordArgs fail if unexpected keys are passed in

Author: abevoelker

lib/contracts/builtin_contracts.rb

@@ -385,9 +385,10 @@ def initialize(options)
     end
 
     def valid?(hash)
-      options.all? do |key, contract|
-        Optional._valid?(hash, key, contract)
-      end
+      (hash.keys - options.keys == []) &&
+        options.all? do |key, contract|
+          Optional._valid?(hash, key, contract)
+        end
     end
 
     def to_s

spec/builtin_contracts_spec.rb

@@ -332,6 +332,24 @@
     end
   end
 
+  describe "KeywordArgs:" do
+    it "should pass for exact correct input" do
+      expect { @o.person_keywordargs(:name => "calvin", :age => 10) }.to_not raise_error
+    end
+
+    it "should fail if some keys don't have contracts" do
+      expect { @o.person_keywordargs(:name => "calvin", :age => 10, :foo => "bar") }.to raise_error(ContractError)
+    end
+
+    it "should fail if a key with a contract on it isn't provided" do
+      expect { @o.person_keywordargs(:name => "calvin") }.to raise_error(ContractError)
+    end
+
+    it "should fail for incorrect input" do
+      expect { @o.person_keywordargs(:name => 50, :age => 10) }.to raise_error(ContractError)
+    end
+  end
+
   describe "Optional:" do
     it "can't be used outside of KeywordArgs" do
       expect do

spec/fixtures/fixtures.rb

@@ -113,6 +113,10 @@ def hash_complex_contracts(data)
   def nested_hash_complex_contracts(data)
   end
 
+  Contract KeywordArgs[:name => String, :age => Fixnum] => nil
+  def person_keywordargs(data)
+  end
+
   Contract [Or[TrueClass, FalseClass]] => nil
   def array_complex_contracts(data)
   end