Drop python3 support in emsdk.py

Fixes: #1592

Author: sbc100

.circleci/config.yml

@@ -81,14 +81,7 @@ jobs:
           name: install python deps
           command: |
             apt-get update -q
-            apt-get install -q -y python2 python3-pip
-      - run:
-          name: python2 flake8
-          command: |
-            curl https://bootstrap.pypa.io/pip/2.7/get-pip.py --output get-pip.py
-            python2 get-pip.py
-            python2 -m pip install flake8==3.9.2
-            python2 -m flake8 --show-source --statistics --extend-exclude=./scripts
+            apt-get install -q -y python3-pip
       - run:
           name: python3 flake8
           command: |
@@ -138,22 +131,18 @@ jobs:
       name: win/server-2019
       shell: bash.exe
     environment:
-      # We need python installed before we can test anytyhing.
-      # There seems to be undocument copy of python installed here. Hopefully
-      # if this disappears there will be another way of getting a re-installed
-      # version.
-      PYTHON_BIN: "C:\\Python27amd64"
       PYTHONUNBUFFERED: "1"
       EMSDK_NOTTY: "1"
     steps:
       - checkout
-      - run:
-          name: Add python to bash path
-          command: echo "export PATH=\"$PATH:/c/python27amd64/\"" >> $BASH_ENV
+      - run: where python
+      - run: where python3
+
       - run:
           name: Install latest
           shell: cmd.exe
           command: test\test.bat
+
       - run:
           name: test.py
           command: |

emsdk.py

@@ -1,11 +1,9 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 # Copyright 2019 The Emscripten Authors.  All rights reserved.
 # Emscripten is available under two separate licenses, the MIT license and the
 # University of Illinois/NCSA Open Source License.  Both these licenses can be
 # found in the LICENSE file.
 
-from __future__ import print_function
-
 import copy
 from collections import OrderedDict
 import errno
@@ -22,21 +20,16 @@
 import sysconfig
 import zipfile
 if os.name == 'nt':
-  try:
-    import winreg
-  except ImportError:
-    # old python 2 name
-    import _winreg as winreg
+  import winreg
   import ctypes.wintypes
 
-if sys.version_info >= (3,):
-  from urllib.parse import urljoin
-  from urllib.request import urlopen
-  import functools
-else:
-  from urlparse import urljoin
-  from urllib2 import urlopen
+from urllib.parse import urljoin
+from urllib.request import urlopen
+import functools
 
+if sys.version_info < (3, 0):
+  print(f'error: emsdk requires python 3.0 or above ({sys.executable} {sys.version})', file=sys.stderr)
+  sys.exit(1)
 
 emsdk_packages_url = 'https://storage.googleapis.com/webassembly/emscripten-releases-builds/deps/'
 

test/test.bat

@@ -1,5 +1,4 @@
 :: equivalent of test.sh as windows bat file
-set PATH=%PATH%;%PYTHON_BIN%
 CALL emsdk install latest
 CALL emsdk activate latest
 CALL emsdk_env.bat