add requirements.txt for developers

.github/workflows/build_doc.yml

@@ -21,7 +21,7 @@ jobs:
 
       - name: Build docs
         run: |
-          pip install -r requirements.txt
+          pip install -r requirements-dev.txt
           pip install .
           cd docs
           make html

.github/workflows/lint.yml

@@ -14,22 +14,22 @@ jobs:
         with:
           python-version: 3.7
 
+      - name: Install requirements
+        run: |
+            pip install -r requirements-dev.txt
+
       - name: Check order of imports with isort
         run: |
-          pip install isort
           isort --profile black --check mcx tests
 
       - name: Check PEP8 compliance with flake8
         run: |
-          pip install flake8
           flake8 mcx tests --count --ignore=E501,E203,E731,W503 --show-source --statistics
 
       - name: Check formatting with black
         run: |
-          pip install black
           black --check mcx tests
 
       - name: Check types with mypy
         run: |
-          pip install mypy
           mypy mcx tests

.github/workflows/test.yml

@@ -24,6 +24,5 @@ jobs:
 
       - name: Run the tests with pytest
         run: |
-          pip install pytest
-          pip install pytest-xdist
+          pip install -r requirements-dev.txt
           pytest -n 4 tests 

requirements-dev.txt

@@ -0,0 +1,8 @@
+black==20.8b1
+flake8==3.8.4
+isort==5.6.4
+mypy==0.790
+nord-pygments==0.0.3
+pytest==6.1.2
+pytest-xdist==2.1.0
+Sphinx==3.3.1