Add spec for Hash class.

Author: vidarh

spec/hash.rb

@@ -0,0 +1,70 @@
+
+module Test
+  eval(File.read(File.expand_path(File.dirname(__FILE__)+'/../lib/core/hash.rb')))
+  eval(File.read(File.expand_path(File.dirname(__FILE__)+'/../lib/core/hash_ext.rb')))
+end
+
+describe Hash do
+  it "should return inserted items in insertion order" do
+    h = Test::Hash.new
+    h["xyz"] = 1
+    h["abc"] = 2
+    h["ghi"] = 3
+    h["def"] = 4
+    h.to_a.should eq [["xyz",1],["abc",2],["ghi",3],["def",4]]
+  end
+
+  it "should return inserted items in insertion order after a #delete" do
+    h = Test::Hash.new
+    h["xyz"] = 1
+    h["abc"] = 2
+    h["ghi"] = 3
+    h["def"] = 4
+    h.delete("abc")
+    h.to_a.should eq [["xyz",1],["ghi",3],["def",4]]
+  end
+
+  it "should return inserted items in insertion order after a #delete and re-insert" do
+    h = Test::Hash.new
+    h["xyz"] = 1
+    h["abc"] = 2
+    h["ghi"] = 3
+    h["def"] = 4
+    h.delete("abc")
+    h["abc"] = 5
+    h.to_a.should eq [["xyz",1],["ghi",3],["def",4],["abc", 5]]
+  end
+
+  it "after a reinsert with the same key, there should be no Deleted entries" do
+    h = Test::Hash.new
+    h["xyz"] = 1
+    p h._data
+    h.delete("xyz").should eq 1
+    p h._state
+    p h._data
+    h["xyz"] = 1
+    p h._state
+    p h._data
+    h._data.compact.should eq ["xyz", 1]
+    h.to_a.should eq [["xyz", 1]]
+
+    h["abc"] = 2
+    # FIXME: The result of this is unstable because
+    # `#hash` changes from run to run under MRI
+    #h._data.compact.should eq ["xyz", 1,24, "abc", 2, 0]
+    h.to_a.should eq [["xyz", 1], ["abc", 2]]
+    p :xyz_abc
+    p h._state
+    p h._data
+    h.delete("xyz").should eq 1
+    p :abc
+    p h._state
+    p h._data
+    h.to_a.should eq [["abc", 2]]
+    h["xyz"] = 3
+    p :abc_xyz
+    p h._state
+    p h._data
+    h.to_a.should eq [["abc", 2], ["xyz", 3]]
+  end
+end