29b91e38e0
Addresses emscripten-core/emscripten#8792 I've found what's the reason of the strange behaviour of last changes (#273). In order to reproduce this problem it's needed: To don't have python3 installed in system To have pyenv with installed at least one version from each family, like: pyenv install 3.7.0 pyenv install 2.7.15 To activate a version from python2 pyenv local 2.7.15 Then we have a strange situation that python3 is available as a command, but it's just a mock for pyenv: ➜ pyenv versions system * 2.7.15 (set by /home/trzeci/Projects/emsdk/.python-version) 3.7.0 ➜ which python3 ~/.pyenv/shims/python3 ➜ python3 --version pyenv: python3: command not found The `python3' command exists in these Python versions: 3.7.0 ➜ ./emsdk --help pyenv: python3: command not found The `python3' command exists in these Python versions: 3.7.0 As you see in an example above I didn't even call emsdk script, just tried to execute python3 --version and I've got exactly the same error. The problem of pyenv is that even if python3 isn't active it's available in the system PATH. Calling ./emsdk --help get's the same error, as python3 was used. At the moment this entirely breaks logic in python_selector and in pyenv working command is indistinguishable from stub python command. @kripken: A couple of ways to go from here: revert logic of python_selector and advertise mac users to use python3 keep logic and advertise pyenv users to use python3 This PR: extend logic of python_selector by checking if found python command is valid (for the instance by calling python --version), this will filter out false positive matches that coming from pyenv After patch: ➜ pyenv versions system * 2.7.15 (set by /home/trzeci/Projects/emsdk/.python-version) 3.7.0 ➜ which python3 ~/.pyenv/shims/python3 ➜ python3 --version pyenv: python3: command not found The `python3' command exists in these Python versions: 3.7.0 ➜ ./emsdk --help emsdk: Available commands: emsdk list [--old] [--uses] - Lists all available SDKs and tools and their current installation status. With the --old .... As you can see python3 --version command fails as it was, but that's expected behaviour. What's important is that ./emsdk --help gets executed as python_selector recognizes a stub.
34 lines
1.2 KiB
Python
Executable File
34 lines
1.2 KiB
Python
Executable File
#!/usr/bin/env python
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# Copyright 2019 The Emscripten Authors. All rights reserved.
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# Emscripten is available under two separate licenses, the MIT license and the
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# University of Illinois/NCSA Open Source License. Both these licenses can be
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# found in the LICENSE file.
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"""Provides a way to run a script on the preferred Python version"""
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import os
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import subprocess
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import sys
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def which(program):
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for path in [""] + os.environ.get("PATH", "").split(os.pathsep):
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exe_file = os.path.join(path, program)
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if os.path.isfile(exe_file) and os.access(exe_file, os.X_OK):
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# in case of pyenv we might have `python3` command available, but it's just a stub
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# https://github.com/emscripten-core/emscripten/issues/8792
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p = subprocess.Popen([exe_file, "--version"], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
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p.communicate()
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if p.returncode == 0:
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return exe_file
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return None
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# Look for the best choice for python, favours Python3 over Python2
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# In case of Windows it uses always python that was used for this script
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if sys.platform in ["linux", "linux2", "darwin"]:
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python = which("python3") or which("python") or sys.executable
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else:
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python = sys.executable
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sys.exit(subprocess.call([python] + sys.argv[1:])) |