fix latex_transformer and add test

converters/latex_transformer.py

@@ -63,7 +63,7 b' def remove_math_space(text):'
                 math_lines += 1
                 if math_lines > 1:
                     within_math = False
-                    ptext = ptext+text[math_start_index:index]+"\n"
+                    ptext = ptext+text[math_start_index:index]
 
         # Remember the last character so we can easily watch
         # for backslashes

tests/test_transformers.py

@@ -11,6 +11,15 b' def test_space(input, reference):'
 
 
 def test_evens():
+    unchanged = [
+        """
+        you should be able to type
+
+            $ a single dollar and go to the line
+
+        it shouldn't be transformed.
+        """
+            ]
     references = [
             ('$e$','$e$'),
             ('$ e $','$e$'),
@@ -19,7 +28,11 b' def test_evens():'
             ('xxx$e^i $yyy','xxx$e^i$yyy'),
             ('xxx$ e^i$yyy','xxx$e^i$yyy'),
             ('\$ e $ e $','\$ e $e$'),
+            ('',''),
             ]
 
     for k,v in references :
         yield test_space, k,v
+
+    for unch in unchanged :
+        yield test_space, unch, unch