Relax dependency minimum versions

Specifying a floor, but not a ceiling, for core dependencies should help
prevent dependency resolution conflicts. Dependencies that affect
functional test output are pinned more tightly.

.github/workflows/main.yml

@@ -86,7 +86,7 @@ jobs:
       - name: Setup Python
         uses: actions/setup-python@v2
         with:
-          python-version: 3.6
+          python-version: "3.x"
       - name: Set pip cache (Linux)
         uses: actions/cache@v1
         if: startsWith(runner.os, 'Linux')
@@ -110,7 +110,7 @@ jobs:
       - name: Setup Python
         uses: actions/setup-python@v2
         with:
-          python-version: 3.6
+          python-version: "3.x"
       - name: Set pip cache (Linux)
         uses: actions/cache@v1
         if: startsWith(runner.os, 'Linux')
@@ -136,7 +136,7 @@ jobs:
       - name: Setup Python
         uses: actions/setup-python@v2
         with:
-          python-version: 3.7
+          python-version: "3.x"
       - name: Check release
         id: check_release
         run: |

pyproject.toml

@@ -31,20 +31,21 @@ classifiers = [
 
 [tool.poetry.dependencies]
 python = "^3.6"
-blinker = "^1.4"
+blinker = ">=1.4"
-docutils = "^0.16"
+docutils = ">=0.16"
-feedgenerator = "^1.9"
+feedgenerator = ">=1.9"
-jinja2 = "~2.11"
+jinja2 = ">=2.7"
-pygments = "^2.6"
+pygments = ">=2.6"
-python-dateutil = "^2.8"
+python-dateutil = ">=2.8"
-pytz = "^2020.1"
+pytz = ">=2020.1"
-unidecode = "^1.1"
+unidecode = ">=1.1"
-markdown = {version = "^3.2", optional = true}
+markdown = {version = ">=3.1", optional = true}
 
 [tool.poetry.dev-dependencies]
 BeautifulSoup4 = "^4.9"
+jinja2 = "~2.11"
 lxml = "^4.3"
-markdown = "~3.3.3"
+markdown = "~3.3.4"
 typogrify = "^2.0"
 sphinx = "^3.0"
 sphinx_rtd_theme = "^0.5"
@@ -56,7 +57,7 @@ pytest-cov = "^2.8"
 pytest-pythonpath = "^0.7.3"
 pytest-sugar = "^0.9.4"
 pytest-xdist = "^2.0"
-tox = "^3.13"
+tox = {version = "^3.13", optional = true}
 flake8 = "^3.8"
 flake8-import-order = "^0.18.1"
 invoke = "^1.3"

requirements/test.pip

@@ -1,11 +1,11 @@
 # Tests
-Pygments==2.8.0
+Pygments==2.8.1
 pytest
 pytest-cov
 pytest-xdist[psutil]
 
 # Optional Packages
-Markdown==3.3.3
+Markdown==3.3.4
 BeautifulSoup4
 lxml
 typogrify

setup.py

@@ -8,7 +8,7 @@ from setuptools import find_packages, setup
 
 version = "4.5.4"
 
-requires = ['feedgenerator >= 1.9', 'jinja2 >= 2.11', 'pygments',
+requires = ['feedgenerator >= 1.9', 'jinja2 >= 2.7', 'pygments',
             'docutils>=0.15', 'pytz >= 0a', 'blinker', 'unidecode',
             'python-dateutil']