chore: drop support for Python 3.6 (#3)

* chore: drop support for Python 3.6

* fix: corrects build

.github/workflows/build.yml

@@ -20,7 +20,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        pythonversion: ["3.6", "3.7", "3.8", "3.9"]
+        pythonversion: ["3.7", "3.8", "3.9"]
     steps:
       - name: Checkout Repository
         uses: actions/checkout@v2

CHANGELOG.md

@@ -1,5 +1,11 @@
 # CHANGELOG
 
+## v2.3.0 (2021-09-20)
+
+* Drop support for Python 3.6
+* Replaces the `mock` library with the builtin `unittest.mock` library
+* Reworks tests to use `io.StringIO()` instead of actual temp files
+
 ## v2.2.0 (2021-04-12)
 
 * Fixed a bug when using this as a CLI tool and the tool wouldn't accept the path arguments (eg: TypeError: expected str, bytes or os.PathLike object, not TextIOWrapper)

diff_tool/diff.py

@@ -2,29 +2,29 @@
 import difflib
 
 
-class Cli():
+class Cli:
     def __init__(self):
         parser = argparse.ArgumentParser(
-            description='Display a diff between two files in HTML.'
+            description='Display a diff between two files in HTML.',
         )
         parser.add_argument(
             '-f1',
             '--file1',
             required=True,
-            help='The path to the base file to compare a second file to.'
+            help='The path to the base file to compare a second file to.',
         )
         parser.add_argument(
             '-f2',
             '--file2',
             required=True,
-            help='The path to the second file compared to the base file.'
+            help='The path to the second file compared to the base file.',
         )
         parser.add_argument(
             '-o',
             '--output',
             required=False,
             default='diff.html',
-            help='The output to the output file including filename.'
+            help='The output to the output file including filename.',
         )
         parser.parse_args(namespace=self)
 
@@ -36,11 +36,10 @@ def run(self):
         )
 
 
-class DiffTool():
+class DiffTool:
     @staticmethod
     def run(file1, file2, output='diff.html'):
-        """Display a diff between two files in HTML.
-        """
+        """Display a diff between two files in HTML."""
         file1_content = DiffTool._open_file(file1)
         file2_content = DiffTool._open_file(file2)
         diff = DiffTool.generate_diff(file1_content, file2_content)
@@ -49,8 +48,7 @@ def run(file1, file2, output='diff.html'):
 
     @staticmethod
     def generate_diff(file1, file2):
-        """Generate the content for the diff file
-        """
+        """Generate the content for the diff file"""
         generated_diff = difflib.HtmlDiff().make_file(
             file1,
             file2,

setup.py

@@ -6,14 +6,13 @@
 DEV_REQUIREMENTS = [
     'coveralls == 3.*',
     'flake8',
-    'mock == 4.*',
     'pytest == 6.*',
     'pytest-cov == 2.*',
 ]
 
 setuptools.setup(
     name='diff-tool',
-    version='2.2.0',
+    version='2.3.0',
     description='Display a diff between two files in HTML.',
     long_description=long_description,
     long_description_content_type="text/markdown",
@@ -27,12 +26,12 @@
         "Operating System :: OS Independent",
     ],
     extras_require={
-        'dev': DEV_REQUIREMENTS
+        'dev': DEV_REQUIREMENTS,
     },
     entry_points={
         'console_scripts': [
-            'diff-tool=diff_tool.diff:main'
-        ]
+            'diff-tool=diff_tool.diff:main',
+        ],
     },
-    python_requires='>=3.6',
+    python_requires='>=3.7',
 )

test/unit/test_diff.py

@@ -1,23 +1,31 @@
-import mock
+import io
+from unittest.mock import mock_open, patch
+
 from diff_tool import DiffTool
 
 
-@mock.patch('diff_tool.diff.DiffTool._open_file')
-@mock.patch('diff_tool.diff.DiffTool._write_file')
+@patch('diff_tool.diff.DiffTool._open_file')
+@patch('diff_tool.diff.DiffTool._write_file')
 def test_diff_run(mock_write, mock_open):
-    DiffTool.run(
-        'setup.py',
-        'README.md',
-        'output.html'
-    )
+    DiffTool.run('setup.py', 'README.md', 'output.html')
+
     assert mock_open.call_count == 2
     mock_write.assert_called_once()
 
 
 def test_generate_diff():
+    """Here we create mocked files in memory and generate a diff
+    with their separate file content.
+    """
+    file1 = io.StringIO()
+    file2 = io.StringIO()
+
+    file1.write('Hello')
+    file2.write('Hello World')
+
     result = DiffTool.generate_diff(
-        'test/files/file1.txt',
-        'test/files/file2.txt',
+        file1,
+        file2,
     )
 
     assert '<!DOCTYPE html' in result
@@ -30,7 +38,7 @@ def test_open_file():
 
 
 def test_write_file():
-    with mock.patch('builtins.open', mock.mock_open()) as mocked_file:
+    with patch('builtins.open', mock_open()) as mocked_file:
         DiffTool._write_file('file_content', 'test.txt')
 
         mocked_file.assert_called_with('test.txt', 'w')