Support unittests in addition to doctests

The Python libraries come with two ways of writing unittests:
module unittest, and module doctest. In some cases, unittest
is more natural (less cumbersome) than doctest.

Wrote tests on xmlWriter for illustration.

Lib/fontTools/misc/xmlWriter_test.py

@@ -0,0 +1,67 @@
+from __future__ import print_function, division, absolute_import
+from fontTools.misc.py23 import *
+from cStringIO import StringIO
+import unittest
+from .xmlWriter import XMLWriter
+
+HEADER = '<?xml version="1.0" encoding="utf-8"?>\n'
+
+class TestXMLWriter(unittest.TestCase):
+
+	def test_comment_escaped(self):
+		writer = XMLWriter(StringIO())
+		writer.comment("This&that are <comments>")
+		self.assertEquals(HEADER + "<!-- This&amp;that are &lt;comments&gt; -->", writer.file.getvalue())
+
+	def test_comment_multiline(self):
+		writer = XMLWriter(StringIO())
+		writer.comment("Hello world\nHow are you?")
+		self.assertEquals(HEADER + "<!-- Hello world\n     How are you? -->", writer.file.getvalue())
+
+	def test_write(self):
+		writer = XMLWriter(StringIO())
+		writer.write("foo&bar")
+		self.assertEquals(HEADER + "foo&amp;bar", writer.file.getvalue())
+
+	def test_indent_dedent(self):
+		writer = XMLWriter(StringIO())
+		writer.write("foo")
+		writer.newline()
+		writer.indent()
+		writer.write("bar")
+		writer.newline()
+		writer.dedent()
+		writer.write("baz")
+		self.assertEquals(HEADER + "foo\n  bar\nbaz", writer.file.getvalue())
+
+	def test_writecdata(self):
+		writer = XMLWriter(StringIO())
+		writer.writecdata("foo&bar")
+		self.assertEquals(HEADER + "<![CDATA[foo&bar]]>", writer.file.getvalue())
+
+	def test_simpletag(self):
+		writer = XMLWriter(StringIO())
+		writer.simpletag("tag", a="1", b="2")
+		self.assertEquals(HEADER + '<tag a="1" b="2"/>', writer.file.getvalue())
+
+	def test_begintag_endtag(self):
+		writer = XMLWriter(StringIO())
+		writer.begintag("tag", attr="value")
+		writer.write("content")
+		writer.endtag("tag")
+		self.assertEquals(HEADER + '<tag attr="value">content</tag>', writer.file.getvalue())
+
+	def test_dumphex(self):
+		writer = XMLWriter(StringIO())
+		writer.dumphex("Type is a beautiful group of letters, not a group of beautiful letters.")
+		self.assertEquals(HEADER + "\n".join([
+		    "54797065 20697320 61206265 61757469",
+		    "66756c20 67726f75 70206f66 206c6574",
+		    "74657273 2c206e6f 74206120 67726f75",
+		    "70206f66 20626561 75746966 756c206c",
+		    "65747465 72732e  \n"]), writer.file.getvalue())
+
+
+if __name__ == '__main__':
+    unittest.main()
+

run-tests.sh

@@ -2,7 +2,7 @@
 cd Lib
 PYTHONPATH=".:$PYTHONPATH"
 export PYTHONPATH
-TESTS=`git grep -l doctest`
+TESTS=`git grep -l -e doctest -e unittest`
 ret=0
 for test in $TESTS; do
 	echo "Running tests in $test"