Improved README to make it easier to cut-and-paste from the code examples

Also:
- Added type hints for a few utility functions in tableformatter.py
- Added unit tests for a few utility functions in tableformatter.py

Author: tleonhardt

README.md

@@ -50,13 +50,13 @@ to this function is ``rows`` which is an Iterable of Iterables such as a list of
 a 2D [numpy](http://www.numpy.org) array.  ``generate_table`` outputs a nicely formatted table:
 
 ```Python
->>> from tableformatter import generate_table
+from tableformatter import generate_table
 
->>> rows = [('A1', 'A2', 'A3', 'A4'),
-...         ('B1', 'B2\nB2\nB2', 'B3', 'B4'),
-...         ('C1', 'C2', 'C3', 'C4'),
-...         ('D1', 'D2', 'D3', 'D4')]
->>> print(generate_table(rows))
+rows = [('A1', 'A2', 'A3', 'A4'),
+        ('B1', 'B2\nB2\nB2', 'B3', 'B4'),
+        ('C1', 'C2', 'C3', 'C4'),
+        ('D1', 'D2', 'D3', 'D4')]
+print(generate_table(rows))
 ╔════╤════╤════╤════╗
 ║ A1 │ A2 │ A3 │ A4 ║
 ║ B1 │ B2 │ B3 │ B4 ║
@@ -74,8 +74,8 @@ Column Headers
 The second argument to ``generate_table`` named ``columns`` is optional and defines a list of column headers to be used.
 
 ```Python
->>> cols = ['Col1', 'Col2', 'Col3', 'Col4']
->>> print(generate_table(rows, cols))
+cols = ['Col1', 'Col2', 'Col3', 'Col4']
+print(generate_table(rows, cols))
 ╔══════╤══════╤══════╤══════╗
 ║ Col1 │ Col2 │ Col3 │ Col4 ║
 ╠══════╪══════╪══════╪══════╣
@@ -99,9 +99,9 @@ Supported grid sytles are:
 * **SparseGrid** - sparse grid with no lines at all to conserve both vertical and horizontal space
 
 ```Python
->>> from tableformatter import FancyGrid
+from tableformatter import FancyGrid
 
->>> print(generate_table(rows, grid_style=FancyGrid))
+print(generate_table(rows, grid_style=FancyGrid))
 ╔════╤════╤════╤════╗
 ║ A1 │ A2 │ A3 │ A4 ║
 ╟────┼────┼────┼────╢
@@ -122,7 +122,7 @@ this and print "rows" up-to-down and "columns" left-to-right then that is easily
 to ``generate_table``:
 
 ```Python
->>> print(generate_table(rows, cols, transpose=True))
+print(generate_table(rows, cols, transpose=True))
 ╔══════╦════╤════╤════╤════╗
 ║ Col1 ║ A1 │ B1 │ C1 │ D1 ║
 ║ Col2 ║ A2 │ B2 │ C2 │ D2 ║

tableformatter.py

@@ -37,7 +37,7 @@ def __subclasshook__(cls, C):
 __version__ = '0.1.0'
 
 
-def _text_wrap(text, width=70):
+def _text_wrap(text: str, width: int=70) -> List[str]:
     """Wrap a single paragraph of text, returning a list of wrapped lines.
 
     Reformat the single paragraph in 'text' so it fits in lines of no
@@ -225,7 +225,7 @@ def _wrap_chunks(self, chunks):
         return lines
 
 
-def _translate_tabs(text):
+def _translate_tabs(text: str) -> str:
     """Translate tab characters into spaces for measurement"""
     tabpos = text.find('\t')
     while tabpos >= 0:
@@ -239,7 +239,7 @@ def _translate_tabs(text):
     return text
 
 
-def _printable_width(text):
+def _printable_width(text: str) -> int:
     """Returns the printable width of a string accounting for escape characters and wide-display unicode characters"""
     return _wcswidth(_translate_tabs(text))
 

tests/test_utils.py

@@ -0,0 +1,66 @@
+# coding=utf-8
+"""
+Unit testing of tableformatter utility functtions.
+"""
+import pytest
+
+import tableformatter as tf
+
+
+@pytest.fixture
+def empty_text():
+    return ''
+
+
+@pytest.fixture
+def sample_text():
+    return 'FooBar'
+
+@pytest.fixture
+def tabbed_text():
+    return 'Foo\tBar'
+
+
+# Test text wrapping
+def test_empty_wrap(empty_text):
+    expected = []
+    wrapped = tf._text_wrap(empty_text)
+    assert expected == wrapped
+
+def test_no_wrap(sample_text):
+    expected = [sample_text]
+    wrapped = tf._text_wrap(sample_text)
+    assert expected == wrapped
+
+def test_simple_wrap(sample_text):
+    expected = ['Foo', 'Bar']
+    wrapped = tf._text_wrap(sample_text, width=3)
+    assert expected == wrapped
+
+
+# Test tab translation and printable width calculation
+def test_empty_translation(empty_text):
+    expected = empty_text
+    translated = tf._translate_tabs(empty_text)
+    assert expected == translated
+
+def test_empty_width(empty_text):
+    assert tf._printable_width(empty_text) == len(empty_text)
+
+def test_translation_no_tabs(sample_text):
+    expected = sample_text
+    translated = tf._translate_tabs(sample_text)
+    assert expected == translated
+
+def test_width_no_tabs(sample_text):
+    assert tf._printable_width(sample_text) == len(sample_text)
+
+def test_translation_with_tabs(tabbed_text):
+    expected = 'Foo Bar'
+    translated = tf._translate_tabs(tabbed_text)
+    assert expected == translated
+    assert expected != tabbed_text
+
+def test_width_with_tabs(tabbed_text):
+    expected = 'Foo Bar'
+    assert tf._printable_width(tabbed_text) == len(expected)