feat: adds version flag

.coveragerc

@@ -1,2 +1,4 @@
 [run]
-omit = pip_tree/cli.py
+omit =
+    pip_tree/cli.py
+    pip_tree/_version.py

CHANGELOG.md

@@ -1,5 +1,9 @@
 # CHANGELOG
 
+## v3.1.0 (2023-08-24)
+
+- Adds `--version` flag
+
 ## v3.0.0 (2023-07-01)
 
 - Drop support for Python 3.7

pip_tree/_version.py

@@ -0,0 +1 @@
+__version__ = '3.1.0'

pip_tree/cli.py

@@ -2,6 +2,7 @@
 import json
 
 import pip_tree
+from pip_tree._version import __version__
 
 
 class PipTreeCli:
@@ -20,6 +21,11 @@ def __init__(self):
                 ' the virtual environment Pip Tree is run from will be used.'
             ),
         )
+        parser.add_argument(
+            '--version',
+            action='version',
+            version=f'%(prog)s {__version__}',
+        )
         parser.parse_args(namespace=self)
 
     def generate_console_output(self):

setup.py

@@ -1,16 +1,26 @@
+import re
+
 import setuptools
 
 
-with open('README.md', 'r') as fh:
-    long_description = fh.read()
+with open('README.md', 'r') as readme_file:
+    long_description = readme_file.read()
+
+# Inspiration: https://stackoverflow.com/a/7071358/6064135
+with open('pip_tree/_version.py', 'r') as version_file:
+    version_groups = re.search(r"^__version__ = ['\"]([^'\"]*)['\"]", version_file.read(), re.M)
+    if version_groups:
+        version = version_groups.group(1)
+    else:
+        raise RuntimeError('Unable to find version string!')
 
 DEV_REQUIREMENTS = [
     'bandit == 1.7.*',
     'black == 23.*',
     'build == 0.10.*',
     'flake8 == 6.*',
     'isort == 5.*',
-    'mypy == 1.3.*',
+    'mypy == 1.5.*',
     'pytest == 7.*',
     'pytest-cov == 4.*',
     'twine == 4.*',
@@ -19,7 +29,7 @@
 
 setuptools.setup(
     name='pip-tree',
-    version='3.0.0',
+    version=version,
     description='Get the dependency tree of your Python virtual environment via Pip.',
     long_description=long_description,
     long_description_content_type="text/markdown",