moving to a new repo

about_hashes.rb

@@ -0,0 +1,56 @@
+require 'edgecase'
+
+class AboutHashes < EdgeCase::Koan
+  def test_creating_hashes
+    empty_hash = Hash.new
+    assert_equal Hash, empty_hash.class
+    assert_equal({}, empty_hash)
+    assert_equal __, empty_hash.size
+  end
+
+  def test_hash_literals
+    hash = { :one => "uno", :two => "dos" }
+    assert_equal __, hash.size
+  end
+
+  def test_accessing_hashes
+    hash = { :one => "uno", :two => "dos" }
+    assert_equal __, hash[:one]
+    assert_equal __, hash[:two]
+    assert_equal __, hash[:doesnt_exist]
+  end
+
+  def test_changing_hashes
+    hash = { :one => "uno", :two => "dos" }
+    hash[:one] = "eins"
+
+    expected = { :one => __, :two => "dos" }
+    assert_equal expected, hash
+
+    # Bonus Question: Why was "expected" broken out into a variable
+    # rather than used as a literal?
+  end
+
+  def test_hash_is_unordered
+    hash1 = { :one => "uno", :two => "dos" }
+    hash2 = { :two => "dos", :one => "uno" }
+
+    assert_equal hash1, hash2    
+  end
+
+  def test_hash_keys_and_values
+    hash = { :one => "uno", :two => "dos" }
+    assert_equal __, hash.keys
+    assert_equal __, hash.values
+  end
+
+  def test_combining_hashes
+    hash = { "jim" => 53, "amy" => 20, "dan" => 23 }
+    new_hash = hash.merge({ "jim" => 54, "jenny" => 26 })
+
+    assert_not_equal hash, new_hash
+    
+    expected = { "jim" => __, "amy" => 20, "dan" => 23, "jenny" => __ }
+    assert_equal expected, new_hash
+  end
+end