Fix word count edge cases and all error codes

fixit/wordcount.py

@@ -12,7 +12,7 @@ def count_words(text: str) -> int:
         count_words("hello world") returns 2.
         count_words("one two three") returns 3.
     """
-    return len(re.split(r'\s+', text.strip()))
+    return len(text.split())
 
 
 def count_lines(text: str) -> int:
@@ -22,7 +22,7 @@ def count_lines(text: str) -> int:
         count_lines("hello\nworld") returns 2.
         count_lines("hello") returns 1.
     """
-    return len(text.split("\n"))
+    return len(text.splitlines())
 
 
 def count_chars(text: str) -> int:

tests/test_textutils.py

@@ -1,12 +1,10 @@
-import pytest
 from fixit.textutils import is_palindrome, reverse_words, slugify
 
 
 def test_simple_palindrome():
     assert is_palindrome("level")
 
 
-@pytest.mark.xfail(reason="Known bug: case-sensitive")
 def test_palindrome_ignores_case():
     assert is_palindrome("Level")
 

tests/test_wordcount.py

@@ -10,16 +10,22 @@ def test_count_words_extra_spaces():
     assert count_words("hello    world") == 2
 
 
-@pytest.mark.xfail(reason="Known bug: empty string returns 1")
 def test_count_words_empty():
     assert count_words("") == 0
 
 
-@pytest.mark.xfail(reason="Known bug: trailing newline adds a phantom line")
 def test_count_lines_trailing_newline():
     assert count_lines("a\nb\n") == 2
 
 
+def test_count_lines_empty():
+    assert count_lines("") == 0
+
+
+def test_count_words_whitespace_only():
+    assert count_words(" \t\n ") == 0
+
+
 def test_count_chars():
     assert count_chars("abc") == 3