Add deprecation warning for Python 2.7 and 3.6

Author: dolfinus

docs/common_issues/index.rst

@@ -3,8 +3,6 @@ Common issues
 
 .. toctree::
     :maxdepth: 1
-    :caption: Common issues
-    :name: common-issues
 
     all_dirty
     wrong_tag

docs/options/index.rst

@@ -5,8 +5,6 @@ Config options
 
 .. toctree::
     :maxdepth: 1
-    :caption: Config options
-    :name: opts
 
     enabled
     starting_version

docs/schemas/callback/index.rst

@@ -5,7 +5,5 @@ Callback-based release
 
 .. toctree::
     :maxdepth: 1
-    :caption: Callback-based
-    :name: callback
 
     version_callback

docs/schemas/file/index.rst

@@ -5,8 +5,6 @@ File-based release
 
 .. toctree::
     :maxdepth: 1
-    :caption: File-based
-    :name: file
 
     version_file
     dev_release_file

docs/schemas/tag/index.rst

@@ -5,8 +5,6 @@ Tag-based release
 
 .. toctree::
     :maxdepth: 1
-    :caption: Tag-based
-    :name: tag
 
     tag_release
     post_release

docs/substitutions/index.rst

@@ -5,8 +5,6 @@ Template substitutions
 
 .. toctree::
     :maxdepth: 1
-    :caption: Template substitutions
-    :name: template-substitutions
 
     tag
     ccount

setuptools_git_versioning.py

@@ -4,6 +4,8 @@
 import os
 import re
 import subprocess
+import sys
+import warnings
 from datetime import datetime
 from distutils.errors import DistutilsSetupError
 from typing import Any, Callable, List, Optional, Union
@@ -132,10 +134,12 @@ def read_toml(file_name):  # type: (str) -> dict
 # TODO: remove along with version_config
 def parse_config(dist, attr, value):  # type: (Distribution, Any, Any) -> None
     if attr == "version_config" and value is not None:
-        log.warning(
+        warnings.warn(
             "`version_config` option is deprecated "
-            "since setuptools-git-versioning 1.8.0.\n"
-            "Please rename it to `setuptools_git_versioning`"
+            "since setuptools-git-versioning v1.8.0 "
+            "and will be dropped in v2.0.\n"
+            "Please rename it to `setuptools_git_versioning`",
+            category=DeprecationWarning,
         )
 
         if getattr(dist, "setuptools_git_versioning", None) is not None:
@@ -150,10 +154,12 @@ def infer_version(dist):  # type: (Distribution) -> None
     value = getattr(dist, "setuptools_git_versioning", None) or getattr(dist, "version_config", None)
 
     if isinstance(value, bool):
-        log.warning(
+        warnings.warn(
             "Passing boolean value to `version_config`/`setuptools_git_versioning` option is deprecated "
-            "since setuptools-git-versioning 1.8.0.\n"
-            "Please change value to `{'enabled': False/True}`"
+            "since setuptools-git-versioning 1.8.0"
+            "and will be dropped in v2.0.\n"
+            "Please change value to `{'enabled': False/True}`",
+            category=DeprecationWarning,
         )
         value = {"enabled": value}
 
@@ -307,6 +313,15 @@ def version_from_git(
 ):
     # type: (...) -> str
 
+    if sys.version_info < (3, 7):
+        warnings.warn(
+            "Python 2.7 and 3.6 support is deprecated "
+            "since setuptools-git-versioning v1.8.0 "
+            "and will be dropped in v2.0.\n"
+            "Please upgrade your Python version to 3.7+",
+            category=DeprecationWarning,
+        )
+
     # Check if PKG-INFO file exists and Version is present in it
     if os.path.exists("PKG-INFO"):
         with open("PKG-INFO") as f: