add tests for reading an extended file

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_8@8441 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

test/ruby/test_file.rb

@@ -67,4 +67,42 @@ class TestFile < Test::Unit::TestCase
     f.truncate(3)
     assert_equal(nil, f.gets)
   end
+
+  def test_read_all_extended_file
+    f = Tempfile.new("test-extended-file")
+    assert_nil(f.getc)
+    open(f.path, "w") {|g| g.print "a" }
+    assert_equal("a", f.read)
+  end
+
+  def test_gets_extended_file
+    f = Tempfile.new("test-extended-file")
+    assert_nil(f.getc)
+    open(f.path, "w") {|g| g.print "a" }
+    assert_equal("a", f.gets("a"))
+  end
+
+  def test_gets_para_extended_file
+    f = Tempfile.new("test-extended-file")
+    assert_nil(f.getc)
+    open(f.path, "w") {|g| g.print "\na" }
+    assert_equal("a", f.gets(""))
+  end
+
+  def test_each_byte_extended_file
+    f = Tempfile.new("test-extended-file")
+    assert_nil(f.getc)
+    open(f.path, "w") {|g| g.print "a" }
+    result = []
+    f.each_byte {|b| result << b }
+    assert_equal([?a], result)
+  end
+
+  def test_getc_extended_file
+    f = Tempfile.new("test-extended-file")
+    assert_nil(f.getc)
+    open(f.path, "w") {|g| g.print "a" }
+    assert_equal(?a, f.getc)
+  end
+
 end