Update mypy, use Py 3.8 instead of 3.7 for testing

Author: Cito

.travis.yml

@@ -11,15 +11,15 @@ python:
   - pypy3
 matrix:
   include:
-    - python: 3.6
+    - python: 3.8
       env: TOXENV=flake8
-    - python: 3.6
+    - python: 3.8
       env: TOXENV=black
-    - python: 3.6
+    - python: 3.8
       env: TOXENV=import-order
-    - python: 3.6
+    - python: 3.8
       env: TOXENV=mypy
-    - python: 3.6
+    - python: 3.8
       env: TOXENV=manifest
 cache: pip
 install: pip install tox-travis

setup.py

@@ -32,7 +32,7 @@
     "flake8==3.7.9",
     "isort<4.0.0",
     "black==19.10b0",
-    "mypy==0.761",
+    "mypy==0.770",
     "check-manifest>=0.40,<1",
 ] + tests_require
 

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = 
+envlist =
     black,flake8,import-order,mypy,manifest,
     py{27,35,36,37,38,39-dev,py,py3}
 ; requires = tox-conda
@@ -14,42 +14,42 @@ setenv =
     MULTIDICT_NO_EXTENSIONS = 1 ; Related to https://github.com/aio-libs/multidict
     YARL_NO_EXTENSIONS = 1      ; Related to https://github.com/aio-libs/yarl
 install_command = python -m pip install --ignore-installed {opts} {packages}
-whitelist_externals = 
+whitelist_externals =
     python
 deps = -e.[test]
 ; Prevent installing issues: https://github.com/ContinuumIO/anaconda-issues/issues/542
 commands =
     pip install -U setuptools
     py{27,35,py}: pytest tests {posargs}
-    py{36,38,39-dev,py3}: pytest tests tests_py36 {posargs}
-    py{37}: pytest tests tests_py36 {posargs: --cov-report=term-missing --cov=gql}
+    py{36,37,39-dev,py3}: pytest tests tests_py36 {posargs}
+    py{38}: pytest tests tests_py36 {posargs: --cov-report=term-missing --cov=gql}
 
 [testenv:black]
-basepython=python3.6
+basepython=python3.8
 deps = -e.[dev]
 commands =
     black --check gql tests
 
 [testenv:flake8]
-basepython = python3.6
+basepython = python3.8
 deps = -e.[dev]
 commands =
     flake8 gql tests
 
 [testenv:import-order]
-basepython=python3.6
+basepython=python3.8
 deps = -e.[dev]
 commands =
     isort -rc gql/ tests/
 
 [testenv:mypy]
-basepython=python3.6
+basepython=python3.8
 deps = -e.[dev]
 commands =
     mypy gql tests --ignore-missing-imports
 
 [testenv:manifest]
-basepython = python3.6
+basepython = python3.8
 deps = -e.[dev]
 commands =
     check-manifest -v