Require python3 (emscripten-core#11836)

In prep for emscripten 2.0.0 require drop support for python2

Fixes: emscripten-core#7198

.circleci/config.yml

@@ -324,9 +324,7 @@ jobs:
     executor: bionic
     steps:
       - checkout
-      - run: pip2 install flake8==3.7.8
       - run: pip3 install flake8==3.7.8
-      - run: python2 -m flake8 --show-source --statistics
       - run: python3 -m flake8 --show-source --statistics
   test-sanity:
     executor: bionic
@@ -362,19 +360,6 @@ jobs:
             export PATH="${HOME}/.jsvu:${PATH}"
             jsvu --os=default --engines=v8
       - build
-  test-minimal-python2:
-    environment:
-      # PTYHON_BIN is used in this file to control which version of python
-      # we use to run the test runner, and EMSDK_PYTHON is used by emcc and
-      # other tools to determine which version of python to use internally.
-      # These can, by design, vary independently.
-      PYTHON_BIN: "python2"
-      EMSDK_PYTHON: "python2"
-      EMCC_ALLOW_PYTHON2: "1"
-    executor: bionic
-    steps:
-      - run-tests:
-          test_targets: "wasm2.test_hello_world other.test_emcc_size_parsing"
   test-wasm0:
     executor: bionic
     steps:
@@ -505,9 +490,6 @@ workflows:
       - test-sockets-chrome:
           requires:
             - build-linux
-      - test-minimal-python2:
-          requires:
-            - build-linux
       - build-windows
       - test-minimal-windows:
           requires:

ChangeLog.md

@@ -17,6 +17,9 @@ See docs/process.md for how version tagging works.
 
 Current Trunk
 -------------
+- Python2 is no longer supported by Emscripten.  Emsdk now includes a bundled
+  copy of Python3 on both macOS and Windows.  This means that only non-emsdk
+  users and linux users should be effected by this change.
 
 1.40.1: 08/01/2020
 ------------------

em++

@@ -21,10 +21,6 @@ if [ -z "$PYTHON" ]; then
   PYTHON=$(which python 2> /dev/null)
 fi
 
-if [ -z "$PYTHON" ]; then
-  PYTHON=$(which python2 2> /dev/null)
-fi
-
 if [ -z "$PYTHON" ]; then
   echo 'unable to find python in $PATH'
   exit 1

em-config

@@ -21,10 +21,6 @@ if [ -z "$PYTHON" ]; then
   PYTHON=$(which python 2> /dev/null)
 fi
 
-if [ -z "$PYTHON" ]; then
-  PYTHON=$(which python2 2> /dev/null)
-fi
-
 if [ -z "$PYTHON" ]; then
   echo 'unable to find python in $PATH'
   exit 1

emar

@@ -21,10 +21,6 @@ if [ -z "$PYTHON" ]; then
   PYTHON=$(which python 2> /dev/null)
 fi
 
-if [ -z "$PYTHON" ]; then
-  PYTHON=$(which python2 2> /dev/null)
-fi
-
 if [ -z "$PYTHON" ]; then
   echo 'unable to find python in $PATH'
   exit 1

embuilder

@@ -21,10 +21,6 @@ if [ -z "$PYTHON" ]; then
   PYTHON=$(which python 2> /dev/null)
 fi
 
-if [ -z "$PYTHON" ]; then
-  PYTHON=$(which python2 2> /dev/null)
-fi
-
 if [ -z "$PYTHON" ]; then
   echo 'unable to find python in $PATH'
   exit 1

emcc

@@ -21,10 +21,6 @@ if [ -z "$PYTHON" ]; then
   PYTHON=$(which python 2> /dev/null)
 fi
 
-if [ -z "$PYTHON" ]; then
-  PYTHON=$(which python2 2> /dev/null)
-fi
-
 if [ -z "$PYTHON" ]; then
   echo 'unable to find python in $PATH'
   exit 1

emcmake

@@ -21,10 +21,6 @@ if [ -z "$PYTHON" ]; then
   PYTHON=$(which python 2> /dev/null)
 fi
 
-if [ -z "$PYTHON" ]; then
-  PYTHON=$(which python2 2> /dev/null)
-fi
-
 if [ -z "$PYTHON" ]; then
   echo 'unable to find python in $PATH'
   exit 1

emconfigure

@@ -21,10 +21,6 @@ if [ -z "$PYTHON" ]; then
   PYTHON=$(which python 2> /dev/null)
 fi
 
-if [ -z "$PYTHON" ]; then
-  PYTHON=$(which python2 2> /dev/null)
-fi
-
 if [ -z "$PYTHON" ]; then
   echo 'unable to find python in $PATH'
   exit 1

emmake

@@ -21,10 +21,6 @@ if [ -z "$PYTHON" ]; then
   PYTHON=$(which python 2> /dev/null)
 fi
 
-if [ -z "$PYTHON" ]; then
-  PYTHON=$(which python2 2> /dev/null)
-fi
-
 if [ -z "$PYTHON" ]; then
   echo 'unable to find python in $PATH'
   exit 1

emranlib

@@ -21,10 +21,6 @@ if [ -z "$PYTHON" ]; then
   PYTHON=$(which python 2> /dev/null)
 fi
 
-if [ -z "$PYTHON" ]; then
-  PYTHON=$(which python2 2> /dev/null)
-fi
-
 if [ -z "$PYTHON" ]; then
   echo 'unable to find python in $PATH'
   exit 1

emrun

@@ -21,10 +21,6 @@ if [ -z "$PYTHON" ]; then
   PYTHON=$(which python 2> /dev/null)
 fi
 
-if [ -z "$PYTHON" ]; then
-  PYTHON=$(which python2 2> /dev/null)
-fi
-
 if [ -z "$PYTHON" ]; then
   echo 'unable to find python in $PATH'
   exit 1

emscons

@@ -21,10 +21,6 @@ if [ -z "$PYTHON" ]; then
   PYTHON=$(which python 2> /dev/null)
 fi
 
-if [ -z "$PYTHON" ]; then
-  PYTHON=$(which python2 2> /dev/null)
-fi
-
 if [ -z "$PYTHON" ]; then
   echo 'unable to find python in $PATH'
   exit 1

emsize

@@ -21,10 +21,6 @@ if [ -z "$PYTHON" ]; then
   PYTHON=$(which python 2> /dev/null)
 fi
 
-if [ -z "$PYTHON" ]; then
-  PYTHON=$(which python2 2> /dev/null)
-fi
-
 if [ -z "$PYTHON" ]; then
   echo 'unable to find python in $PATH'
   exit 1

site/source/docs/getting_started/downloads.rst

@@ -115,7 +115,8 @@ Windows
 macOS
 +++++
 
-If you use MacOS 10.13.3 or later then you should have a new enough version of Python installed (older versions may not work due to `a GitHub change with SSL <https://github.com/emscripten-core/emscripten/issues/6275>`_). Otherwise you can manually install and use Python 2.7.12 or newer.
+If you the Emscripten SDK it includes a bundled version of Python 3.  Otherwise
+you will need to manually install and use Python 3.5 or newer.
 
 These instructions explain how to install **all** the :ref:`required tools <toolchain-what-you-need>`. You can :ref:`test whether some of these are already installed <toolchain-test-which-dependencies-are-installed>` on the platform and skip those steps.
 
@@ -134,8 +135,6 @@ These instructions explain how to install **all** the :ref:`required tools <tool
 
   -  Download and install latest CMake from `Kitware CMake downloads <http://www.cmake.org/download/>`_.
 
-  .. _getting-started-on-macos-install-python2:
-
 Linux
 +++++
 
@@ -146,16 +145,14 @@ Linux
   ::
 
     # Install Python
-    sudo apt-get install python2.7
+    sudo apt-get install python3
 
     # Install CMake (optional, only needed for tests and building Binaryen)
     sudo apt-get install cmake
 
     # Install Java (optional, only needed for Closure Compiler minification)
     sudo apt-get install default-jre
 
-.. note:: You need Python 2.7.12 or newer because older versions may not work due to `a GitHub change with SSL <https://github.com/emscripten-core/emscripten/issues/6275>`_).
-
 .. note:: If you want to use your system's Node.js instead of the emsdk's, it may be ``node`` instead of ``nodejs``, and you can adjust the ``NODE_JS`` attribute of your ``.emscripten`` file to point to it.
 
 - *Git* is not installed automatically. Git is only needed if you want to use tools from one of the development branches **emscripten-incoming** or **emscripten-master**:

tests/test_other.py

@@ -93,27 +93,6 @@ def decorated(self):
   return decorated
 
 
-def is_python3_version_supported():
-  """Retuns True if the installed python3 version is supported by emscripten.
-
-  Note: Emscripten requires python3.5 or above since python3.4 and below do not
-  support circular dependencies."""
-  try:
-    print('is_python3_version_supported')
-    python3 = shared.which('python3')
-    print('  python3 =', python3)
-    output = shared.run_process([python3, '--version'], stdout=PIPE).stdout
-    print('  output =', output, output.split())
-    output = output.split()[1]
-    # ignore final component which can contains non-integers (e.g 'rc1')
-    version = [int(x) for x in output.split('.')[:2]]
-    return version >= [3, 5]
-  except Exception:
-    # If anything goes wrong (no python3, unexpected output format), then we do
-    # not support this python3
-    return False
-
-
 def encode_leb(number):
   # TODO(sbc): handle larger numbers
   assert(number < 255)
@@ -6822,28 +6801,6 @@ def test_dash_s_no_space(self):
     err = self.expect_fail([EMCC, path_from_root('tests', 'hello_world.cpp'), '-sEXPORTED_FUNCTIONS=["foo"]'])
     self.assertContained('error: undefined exported function: "foo"', err)
 
-  def test_python_2_3(self):
-    # check emcc/em++ can be called by any python
-    def trim_py_suffix(filename):
-      """remove .py from EMCC(=emcc.py)"""
-      return filename[:-3] if filename.endswith('.py') else filename
-
-    def run(python):
-      if python == 'python3':
-        has = is_python3_version_supported()
-      else:
-        has = shared.which(python) is not None
-      print(python, has)
-      if has:
-        print('  checking emcc.py...')
-        self.run_process([python, path_from_root('emcc.py'), '--version'], stdout=PIPE)
-        print('  checking em++.py...')
-        self.run_process([python, path_from_root('em++.py'), '--version'], stdout=PIPE)
-
-    run('python')
-    run('python2')
-    run('python3')
-
   def test_zeroinit(self):
     create_test_file('src.c', r'''
 #include <stdio.h>
@@ -8500,14 +8457,8 @@ def test_autotools_shared_check(self):
     env = os.environ.copy()
     env['LC_ALL'] = 'C'
     expected = ': supported targets:.* elf'
-    for python in [PYTHON, 'python', 'python2', 'python3']:
-      if not shared.which(python):
-        continue
-      if python == 'python3' and not is_python3_version_supported():
-        continue
-      print(python)
-      out = self.run_process([python, path_from_root('emcc.py'), '--help'], stdout=PIPE, env=env).stdout
-      assert re.search(expected, out)
+    out = self.run_process([EMCC, '--help'], stdout=PIPE, env=env).stdout
+    assert re.search(expected, out)
 
   def test_ioctl_window_size(self):
       self.do_other_test(os.path.join('other', 'ioctl', 'window_size'))

tests/test_sanity.py

@@ -200,7 +200,6 @@ def make_executable(name):
         temp_bin = tempfile.mkdtemp()
         make_executable('llvm-dis')
         make_executable('node')
-        make_executable('python2')
         env['PATH'] = temp_bin + os.pathsep + os.environ['PATH']
         output = self.do(command, env=env)
       finally:

tools/gen_struct_info.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 # coding=utf-8
 # Copyright 2013 The Emscripten Authors.  All rights reserved.
 # Emscripten is available under two separate licenses, the MIT license and the

tools/maybe_wasm2js.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/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

tools/run_python.sh

@@ -21,10 +21,6 @@ if [ -z "$PYTHON" ]; then
   PYTHON=$(which python 2> /dev/null)
 fi
 
-if [ -z "$PYTHON" ]; then
-  PYTHON=$(which python2 2> /dev/null)
-fi
-
 if [ -z "$PYTHON" ]; then
   echo 'unable to find python in $PATH'
   exit 1

tools/shared.py

@@ -21,12 +21,8 @@
 import sys
 import tempfile
 
-if sys.version_info < (2, 7, 0):
-  print('emscripten requires python 2.7.0 or above (python 2.7.12 or newer is recommended, older python versions are known to run into SSL related issues, https://github.com/emscripten-core/emscripten/issues/6275)', file=sys.stderr)
-  sys.exit(1)
-
-if sys.version_info[0] == 3 and sys.version_info < (3, 5):
-  print('emscripten requires at least python 3.5 (or python 2.7.12 or above)', file=sys.stderr)
+if sys.version_info < (3, 5):
+  print('error: emscripten requires python 3.5 or above', file=sys.stderr)
   sys.exit(1)
 
 from .toolchain_profiler import ToolchainProfiler