poetry export --with dev fails with: Dependency walk failed

[Lucas-C]

• Poetry version: 1.3.1
• Python version: 3.8.10
• OS version and name: WSL (Ubuntu 20.04.5 LTS)
• pyproject.toml:

[tool.poetry]
name = 'Thing'
version = '1.2.3'
description = 'Dummy'
authors = ['Some One']

[tool.poetry.dev-dependencies]
jsonpickle = '1.4.1'

• I am on the latest stable Poetry version, installed using a recommended method.
• I have searched the issues of this repo and believe that this is not a duplicate.
• I have consulted the FAQ and blog for any relevant entries or release notes.
• If an exception occurs when executing a command, I executed it again in debug mode (-vvv option) and have included the output below.

Issue

When running poetry -vvv export --with dev with the above minimal pyproject.toml, I get the following error:

Loading configuration file /home/lucas_cimon/.config/pypoetry/config.toml
Loading configuration file /home/lucas_cimon/.config/pypoetry/auth.toml
Source (poetry-lockfile): 1 packages found for jsonpickle 1.4.1

  Stack trace:

  12  ~/.local/lib/python3.8/site-packages/cleo/application.py:327 in run
       325│
       326│             try:
     → 327│                 exit_code = self._run(io)
       328│             except BrokenPipeError:
       329│                 # If we are piped to another process, it may close early and send a

  11  ~/.local/lib/python3.8/site-packages/poetry/console/application.py:190 in _run
       188│         self._load_plugins(io)
       189│
     → 190│         exit_code: int = super()._run(io)
       191│         return exit_code
       192│

  10  ~/.local/lib/python3.8/site-packages/cleo/application.py:431 in _run
       429│             io.input.interactive(interactive)
       430│
     → 431│         exit_code = self._run_command(command, io)
       432│         self._running_command = None
       433│

   9  ~/.local/lib/python3.8/site-packages/cleo/application.py:473 in _run_command
       471│
       472│         if error is not None:
     → 473│             raise error
       474│
       475│         return terminate_event.exit_code

   8  ~/.local/lib/python3.8/site-packages/cleo/application.py:457 in _run_command
       455│
       456│             if command_event.command_should_run():
     → 457│                 exit_code = command.run(io)
       458│             else:
       459│                 exit_code = ConsoleCommandEvent.RETURN_CODE_DISABLED

   7  ~/.local/lib/python3.8/site-packages/cleo/commands/base_command.py:119 in run
       117│         io.input.validate()
       118│
     → 119│         status_code = self.execute(io)
       120│
       121│         if status_code is None:

   6  ~/.local/lib/python3.8/site-packages/cleo/commands/command.py:62 in execute
        60│
        61│         try:
     →  62│             return self.handle()
        63│         except KeyboardInterrupt:
        64│             return 1

   5  ~/.local/lib/python3.8/site-packages/poetry_plugin_export/command.py:107 in handle
       105│         exporter.with_credentials(self.option("with-credentials"))
       106│         exporter.with_urls(not self.option("without-urls"))
     → 107│         exporter.export(fmt, Path.cwd(), output or self.io)
       108│

   4  ~/.local/lib/python3.8/site-packages/poetry_plugin_export/exporter.py:86 in export
        84│             raise ValueError(f"Invalid export format: {fmt}")
        85│
     →  86│         getattr(self, self.EXPORT_METHODS[fmt])(cwd, output)
        87│
        88│     def _export_generic_txt(

   3  ~/.local/lib/python3.8/site-packages/poetry_plugin_export/exporter.py:101 in _export_generic_txt
        99│         )
       100│
     → 101│         for dependency_package in get_project_dependency_packages(
       102│             self._poetry.locker,
       103│             project_requires=root.all_requires,

   2  ~/.local/lib/python3.8/site-packages/poetry_plugin_export/walker.py:103 in get_project_dependency_packages
       101│         selected.append(dependency)
       102│
     → 103│     for package, dependency in get_project_dependencies(
       104│         project_requires=selected,
       105│         locked_packages=repository.packages,

   1  ~/.local/lib/python3.8/site-packages/poetry_plugin_export/walker.py:129 in get_project_dependencies
       127│         )
       128│
     → 129│     nested_dependencies = walk_dependencies(
       130│         dependencies=project_requires,
       131│         packages_by_name=packages_by_name,

  RuntimeError

  Dependency walk failed at jsonpickle (==1.4.1)

  at ~/.local/lib/python3.8/site-packages/poetry_plugin_export/walker.py:155 in walk_dependencies
      151│             requirement, packages_by_name, nested_dependencies
      152│         )
      153│
      154│         if not locked_package:
    → 155│             raise RuntimeError(f"Dependency walk failed at {requirement}")
      156│
      157│         if requirement.extras:
      158│             locked_package = locked_package.with_features(requirement.extras)
      159│

[Lucas-C]

Note that I do not have the poetry-plugin-export package installed in my environment

[neersighted]

I'm unable to reproduce this in a container; can you please try the modifying the following reproduction attempt to reproduce?

$ docker run --rm -it python:3.8 bash
# pip install poetry==1.3.1
# poetry new reproduction && cd reproduction
# poetry add --group dev jsonpickle==1.4.1
# poetry export --with dev
[success]

[Lucas-C]

I successfully reproduced the error with those steps:

$ docker run --rm -it python:3.8 bash
# pip install poetry==1.3.1
# cd /var/tmp/
# cat >pyproject.toml <<EOF
[tool.poetry]
name = 'Thing'
version = '1.2.3'
description = 'Dummy'
authors = ['Some One']

[tool.poetry.dev-dependencies]
jsonpickle = '1.4.1'
EOF
# poetry export --with dev

[dimbleby]

Add a dependency `python = "^3.10" (or whatever versions you actually want to support)

[Lucas-C]

Thanks @dimbleby

I was able to solve my issue this way indeed:

[tool.poetry]
name = 'Thing'
version = '1.2.3'
description = 'Dummy'
authors = ['Some One']

[tool.poetry.dependencies]
python = "^3.8"

[tool.poetry.dev-dependencies]
jsonpickle = '1.4.1'

Maybe poetry error message could be improved in that situation?