2 files changed, 21 insertions, 1 deletions
diff --git a/markdown/__init__.py b/markdown/__init__.py
index ae301b5..af5a2c1 100644
--- a/markdown/__init__.py
+++ b/markdown/__init__.py
@@ -367,7 +367,7 @@ class Markdown:
         """
 
         # Fixup the source text
-        if not source:
+        if not source.strip():
             return u""  # a blank unicode string
         try:
             source = unicode(source)
diff --git a/regression-tests.py b/regression-tests.py
index 1b99ff9..7601061 100755
--- a/regression-tests.py
+++ b/regression-tests.py
@@ -12,6 +12,25 @@ from doctest import DocTestSuite
 import os
 import markdown
 
+class TestMarkdown(unittest.TestCase):
+    """ Tests basics of the Markdown class. """
+
+    def setUp(self):
+        """ Create instance of Markdown. """
+        self.md = markdown.Markdown()
+
+    def testBlankInput(self):
+        """ Test blank input. """
+        self.assertEqual(self.md.convert(''), '')
+
+    def testWhitespaceOnly(self):
+        """ Test input of only whitespace. """
+        self.assertEqual(self.md.convert(' '), '')
+
+    def testSimpleInput(self):
+        """ Test simple input. """
+        self.assertEqual(self.md.convert('foo'), '<p>foo</p>')
+
 class TestBlockParser(unittest.TestCase):
     """ Tests of the BlockParser class. """
 
@@ -196,6 +215,7 @@ class TestOrderedDict(unittest.TestCase):
 def suite():
     """ Build a test suite of the above tests and extension doctests. """
     suite = unittest.TestSuite()
+    suite.addTest(unittest.makeSuite(TestMarkdown))
     suite.addTest(unittest.makeSuite(TestBlockParser))
     suite.addTest(unittest.makeSuite(TestBlockParserState))
     suite.addTest(unittest.makeSuite(TestHtmlStash))