Use sys.executable for invoking mypy in runtests if it is >=Python 3.4 (#5702)

emmatyping · web-flow · commit c47511f113a6 · 2018-10-01T14:56:29.000-07:00
diff --git a/README.md b/README.md
@@ -221,7 +221,12 @@ whenever you change branches, merge, rebase, or pull.
 Tests
 -----
 
-See [Test README.md](test-data/unit/README.md)
+The basic way to run tests:
+
+    $ pip3 install -r test-requirements.txt
+    $ ./runtests.py
+
+For more on the tests, see [Test README.md](test-data/unit/README.md)
 
 
 Development status
diff --git a/runtests.py b/runtests.py
@@ -1,13 +1,18 @@
 #!/usr/bin/env python3
 from os import system
-from sys import argv, exit, platform
+from sys import argv, exit, platform, executable, version_info
 
 prog, *args = argv
 
-if platform == 'win32':
-    python_name = 'py -3'
+
+# Use the Python provided to execute the script, or fall back to a sane default
+if version_info >= (3, 4, 0):
+        python_name = executable
 else:
-    python_name = 'python3'
+    if platform == 'win32':
+        python_name = 'py -3'
+    else:
+        python_name = 'python3'
 
 cmds = {
     'self': python_name + ' -m mypy --config-file mypy_self_check.ini -p mypy',
