Installation fails on MacOS

[WilliamVenner]

Python 3.8 was installed by Command Line Tools (Xcode)

dyld[58557]: Library not loaded: @executable_path/../Python3
  Referenced from: /Users/william.venner/Library/Application Support/pypoetry/venv/bin/Python3
  Reason: tried: '/Users/william.venner/Library/Application Support/pypoetry/venv/bin/../Python3' (no such file), '/usr/local/lib/Python3' (no such file), '/usr/lib/Python3' (no such file)

Traceback:

  File "<stdin>", line 892, in main
  File "<stdin>", line 530, in run

Is this a case sensitivity issue?

MacOS Monterey 12.4 on M1 Pro

For anyone stumbling on this

I found installing poetry from homebrew worked fine.

[ifeeltiredboss]

It's the same for MacOS Monterey 12.3 on Intel. Perhaps some errors in paths?

➜  ~ which python3
/usr/bin/python3

[ifeeltiredboss]

Installing python with homebrew and then restarting the install script works fine. But I think it shouldn't be necessary to install another python before installing poetry.

[neersighted]

Looks like macOS's Python is broken. OS-provided Pythons are always touch and go/partially broken, so this is a low priority, but it would be nice to figure out.

[branchv]

The issue here is the macOS-provided python is not relocatable, so venv creates a broken python when using --copies / symlinks=False as our installer does. See python/cpython#82886 (comment)

A simple reproduction:

$ /usr/bin/python3 -m venv --copies --without-pip venv && ./venv/bin/python3
dyld[97998]: Library not loaded: '@executable_path/../Python3'
  Referenced from: '/private/tmp/venv/bin/python3'
  Reason: tried: '/private/tmp/venv/bin/../Python3' (no such file), '/usr/local/lib/Python3' (no such file), '/usr/lib/Python3' (no such file)
fish: Job 1, './venv/bin/python3' terminated by signal SIGABRT (Abort)

Perhaps we should try to detect + handle this case and fallback to symlinks=True

[cjolowicz]

This problem is not limited to Command Line Tools. It applies to any Python on macOS, provided it's built as a framework (--enable-framework). For example, this includes official binaries from python.org and Homebrew. It excludes pyenv which uses the default POSIX build configuration.

From #34 :

The problem appears to be that the installer creates the virtual environment with copies instead of symlinks. This is a good default for Windows, but not for macOS. On macOS, the copied interpreter binary references the Python dynamic library using a path including the full version number. When Homebrew upgrades Python, this path disappears. By contrast, virtual environments created with the default strategy use a symbolic link that remains stable for all releases of a Python feature version (major.minor). Upgrading Python to a maintenance release seamlessly and implicitly upgrades any associated virtual environments.

[cjolowicz]

Looking a bit further into this, there are some differences between these Pythons. According to the CPython issue linked above, Apple's Python uses a relative path to the dynamic library, which always breaks with symlinks=False. Homebrew uses an absolute path, which breaks when you upgrade to a new release of Python. Official binaries from python.org are probably fine (haven't tested this).

In any case, I'd recommend to use symlinks=True except on Windows. This is also the default that the python -m venv command uses.

[windoverwater]

FYI - on my 2020 M1 mini with the latest MacOS, poetry does not install from scratch. FYI - homebrew is installed for other stuff besides python and miniconda is installed for all things python. I am trying to switch a few projects from conda to poetry.

% which python3
/usr/bin/python3
% ls -l /usr/bin/python3
-rwxr-xr-x 76 root wheel 167120 Aug 24 04:59 /usr/bin/python3*

% python3 install-poetry.py
Retrieving Poetry metadata

Welcome to Poetry!

This will download and install the latest version of Poetry,
a dependency and package manager for Python.

It will add the poetry command to Poetry's bin directory, located at:

/Users/sandy/.local/bin

You can uninstall at any time by executing this script with the --uninstall option,
and these changes will be reverted.

Installing Poetry (1.2.1): Creating environment
Traceback (most recent call last):
File "/Users/sandy/repos/github.com/install.python-poetry.org/install-poetry.py", line 940, in
sys.exit(main())
File "/Users/sandy/repos/github.com/install.python-poetry.org/install-poetry.py", line 919, in main
return installer.run()
File "/Users/sandy/repos/github.com/install.python-poetry.org/install-poetry.py", line 550, in run
self.install(version)
File "/Users/sandy/repos/github.com/install.python-poetry.org/install-poetry.py", line 571, in install
with self.make_env(version) as env:
File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/contextlib.py", line 117, in enter
return next(self.gen)
File "/Users/sandy/repos/github.com/install.python-poetry.org/install-poetry.py", line 643, in make_env
raise e
File "/Users/sandy/repos/github.com/install.python-poetry.org/install-poetry.py", line 629, in make_env
yield VirtualEnvironment.make(env_path)
File "/Users/sandy/repos/github.com/install.python-poetry.org/install-poetry.py", line 309, in make
builder = venv.EnvBuilder(clear=True, with_pip=True, symlinks=False)
File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/venv/init.py", line 66, in init
self.symlinks = should_use_symlinks(symlinks)
File "/Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.9/lib/python3.9/venv/init.py", line 31, in should_use_symlinks
raise Exception("This build of python cannot create venvs without using symlinks")
Exception: This build of python cannot create venvs without using symlinks

% git logpp -1
* c8c3ce4 - (HEAD -> main, origin/main, origin/HEAD) (34 hours ago) <pre-commit-ci[bot]> [pre-commit.ci] pre-commit autoupdate
% python3 --version
Python 3.9.6

[abhinavdayal]

python3 -m venv $VENV_PATH
$VENV_PATH/bin/pip install -U pip setuptools
$VENV_PATH/bin/pip install poetry

Using these to install poetry works fine. However this must be repeated for each new project.

[neersighted]

I'm not sure what you mean @abhinavdayal -- Poetry should not be installed in the project environment. The manual or pipx install directions on https://python-poetry.org/docs work just fine in the mean time.