Simplify cross version tests

.travis.yml

@@ -16,8 +16,6 @@ matrix:
 install: pip install coveralls tox
 script: tox
 before_install:
-    # work around https://github.com/travis-ci/travis-ci/issues/8363
-    - which python3.5 || (pyenv install 3.5.4 && pyenv global system 3.5.4)
     - git --version
     - |
         if [ "$LATEST_GIT" = "1" ]; then

CONTRIBUTING.md

@@ -5,9 +5,8 @@
 - The complete test suite depends on having at least the following installed (possibly not
   a complete list)
   - git (A sufficiently newer version is required to run pre-push tests)
-  - python
-  - python3.4 (Required by a test which checks different python versions)
-  - python3.5 (Required by a test which checks different python versions)
+  - python2 (Required by a test which checks different python versions)
+  - python3 (Required by a test which checks different python versions)
   - tox (or virtualenv)
   - ruby + gem
   - docker

testing/resources/arbitrary_bytes_repo/.pre-commit-hooks.yaml

@@ -2,5 +2,5 @@
     name: Python 3 Hook
     entry: python3-hook
     language: python
-    language_version: python3.5
+    language_version: python3
     files: \.py$

testing/resources/python3_hooks_repo/.pre-commit-hooks.yaml

@@ -2,5 +2,5 @@
     name: Python 3 Hook
     entry: python3-hook
     language: python
-    language_version: python3.5
+    language_version: python3
     files: \.py$

testing/resources/python3_hooks_repo/python3_hook/main.py

@@ -4,7 +4,7 @@ import sys
 
 
 def func():
-    print('{}.{}'.format(*sys.version_info[:2]))
+    print(sys.version_info[0])
     print(repr(sys.argv[1:]))
     print('Hello World')
     return 0

tests/repository_test.py

@@ -130,8 +130,8 @@ def test_switch_language_versions_doesnt_clobber(tempdir_factory, store):
         assert ret[0] == 0
         assert _norm_out(ret[1]) == expected_output
 
-    run_on_version('python3.4', b'3.4\n[]\nHello World\n')
-    run_on_version('python3.5', b'3.5\n[]\nHello World\n')
+    run_on_version('python2', b'2\n[]\nHello World\n')
+    run_on_version('python3', b'3\n[]\nHello World\n')
 
 
 @pytest.mark.integration
@@ -140,7 +140,7 @@ def test_versioned_python_hook(tempdir_factory, store):
         tempdir_factory, store, 'python3_hooks_repo',
         'python3-hook',
         [os.devnull],
-        b"3.5\n['" + five.to_bytes(os.devnull) + b"']\nHello World\n",
+        b"3\n['" + five.to_bytes(os.devnull) + b"']\nHello World\n",
     )