added test cases for encryption support

lib/zip/crypto/traditional_encryption.rb

@@ -42,7 +42,7 @@ class TraditionalEncrypter < Encrypter
     def header(crc32)
       [].tap do |header|
         (header_bytesize - 1).times do
-          header << rand(0..255)
+          header << Random.rand(0..255)
         end
         header << (crc32 >> 24)
       end.map{|x| encode x}.pack("C*")

test/crypto/null_encryption_test.rb

@@ -0,0 +1,55 @@
+require 'test_helper'
+
+class NullEncrypterTest < MiniTest::Test
+  def setup
+    @encrypter = ::Zip::NullEncrypter.new
+  end
+
+  def test_header_bytesize
+    assert_equal 0, @encrypter.header_bytesize
+  end
+
+  def test_gp_flags
+    assert_equal 0, @encrypter.gp_flags
+  end
+
+  def test_header
+    [nil, '', 'a' * 10, 0xffffffff].each do |arg|
+      assert_empty @encrypter.header(arg)
+    end
+  end
+
+  def test_encrypt
+    [nil, '', 'a' * 10, 0xffffffff].each do |data|
+      assert_equal data, @encrypter.encrypt(data)
+    end
+  end
+
+  def test_reset!
+    assert_respond_to @encrypter, :reset!
+  end
+end
+
+class NullDecrypterTest < MiniTest::Test
+  def setup
+    @decrypter = ::Zip::NullDecrypter.new
+  end
+
+  def test_header_bytesize
+    assert_equal 0, @decrypter.header_bytesize
+  end
+
+  def test_gp_flags
+    assert_equal 0, @decrypter.gp_flags
+  end
+
+  def test_decrypt
+    [nil, '', 'a' * 10, 0xffffffff].each do |data|
+      assert_equal data, @decrypter.decrypt(data)
+    end
+  end
+
+  def test_reset!
+    assert_respond_to @decrypter, :reset!
+  end
+end

test/crypto/traditional_encryption_test.rb

@@ -0,0 +1,79 @@
+require 'test_helper'
+
+class TraditionalEncrypterTest < MiniTest::Test
+  def setup
+    @encrypter = ::Zip::TraditionalEncrypter.new('password')
+  end
+
+  def test_header_bytesize
+    assert_equal 12, @encrypter.header_bytesize
+  end
+
+  def test_gp_flags
+    assert_equal 1, @encrypter.gp_flags
+  end
+
+  def test_header
+    @encrypter.reset!
+    exepected = [239, 57, 234, 154, 246, 80, 83, 221, 74, 200, 116, 154].pack("C*")
+    Random.stub(:rand, 1) do
+      assert_equal exepected, @encrypter.header(0xffffffff)
+    end
+  end
+
+  def test_encrypt
+    @encrypter.reset!
+    Random.stub(:rand, 1) { @encrypter.header(0xffffffff) }
+    assert_raises(NoMethodError) { @encrypter.encrypt(nil) }
+    assert_raises(NoMethodError) { @encrypter.encrypt(1) }
+    assert_equal '', @encrypter.encrypt('')
+    assert_equal [2, 25, 13, 222, 17, 190, 250, 133, 133, 166].pack("C*"), @encrypter.encrypt('a' * 10)
+  end
+
+  def test_reset!
+    @encrypter.reset!
+    Random.stub(:rand, 1) { @encrypter.header(0xffffffff) }
+    [2, 25, 13, 222, 17, 190, 250, 133, 133, 166].map(&:chr).each do |c|
+      assert_equal c, @encrypter.encrypt('a')
+    end
+    assert_equal 134.chr, @encrypter.encrypt('a')
+    @encrypter.reset!
+    Random.stub(:rand, 1) { @encrypter.header(0xffffffff) }
+    [2, 25, 13, 222, 17, 190, 250, 133, 133, 166].map(&:chr).each do |c|
+      assert_equal c, @encrypter.encrypt('a')
+    end
+  end
+end
+
+class TraditionalDecrypterTest < MiniTest::Test
+  def setup
+    @decrypter = ::Zip::TraditionalDecrypter.new('password')
+  end
+
+  def test_header_bytesize
+    assert_equal 12, @decrypter.header_bytesize
+  end
+
+  def test_gp_flags
+    assert_equal 1, @decrypter.gp_flags
+  end
+
+  def test_decrypt
+    @decrypter.reset!([239, 57, 234, 154, 246, 80, 83, 221, 74, 200, 116, 154].pack("C*"))
+    [2, 25, 13, 222, 17, 190, 250, 133, 133, 166].map(&:chr).each do |c|
+      assert_equal 'a', @decrypter.decrypt(c)
+    end
+  end
+
+  def test_reset!
+    @decrypter.reset!([239, 57, 234, 154, 246, 80, 83, 221, 74, 200, 116, 154].pack("C*"))
+    [2, 25, 13, 222, 17, 190, 250, 133, 133, 166].map(&:chr).each do |c|
+      assert_equal 'a', @decrypter.decrypt(c)
+    end
+    assert_equal 229.chr, @decrypter.decrypt(2.chr)
+    @decrypter.reset!([239, 57, 234, 154, 246, 80, 83, 221, 74, 200, 116, 154].pack("C*"))
+    [2, 25, 13, 222, 17, 190, 250, 133, 133, 166].map(&:chr).each do |c|
+      assert_equal 'a', @decrypter.decrypt(c)
+    end
+  end
+end