[Bug] v.buffer not found in GRASS Conda package

[baharmon]

Describe the bug

Running v.buffer using GRASS 8.4.2 installed using Conda results in the error No such file or directory: 'v.buffer'. See the full error below. Test with a Python script and Jupyter notebook on Mac. Confirmed that v.buffer works as expected in binary installations of GRASS 8.4 & 8.5.

To reproduce with Python

1. Install GRASS using Conda
2. Start a GRASS session
3. Run v.buffer.
4. See error

Example script:

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

# Import libraries
import sys
import subprocess

# Find GRASS Python packages
sys.path.append(
  subprocess.check_output(
    ["grass", "--config", "python_path"],
    text=True
    ).strip()
  )

# Import GRASS packages
import grass.script as gs

# Create a temporary folder
import tempfile
temporary = tempfile.TemporaryDirectory()

# Create a project in the temporary directory
gs.create_project(path=temporary.name, name="xy")

# Initialize project
project = os.path.join(temporary.name, "xy")
gs.setup.init(project)

# Buffer
gs.run_command("v.buffer")

Error report

%runfile /Users/baharmon/Downloads/v_buffer_mwe.py --wdir
---------------------------------------------------------------------------
FileNotFoundError                         Traceback (most recent call last)
File ~/Downloads/v_buffer_mwe.py:27
     24 gs.create_project(path=temporary.name, name="xy")
     26 # Buffer
---> 27 gs.run_command("v.buffer")

File ~/miniconda3/envs/grass/grass84/etc/python/grass/script/core.py:476, in run_command(*args, **kwargs)
    474 if _capture_stderr and "stderr" not in kwargs.keys():
    475     kwargs["stderr"] = PIPE
--> 476 ps = start_command(*args, **kwargs)
    477 if _capture_stderr:
    478     stdout, stderr = ps.communicate()

File ~/miniconda3/envs/grass/grass84/etc/python/grass/script/core.py:431, in start_command(prog, flags, overwrite, quiet, verbose, superquiet, **kwargs)
    425     sys.stderr.write(
    426         "D1/{}: {}.start_command(): {}\n".format(
    427             debug_level(), __name__, " ".join(args)
    428         )
    429     )
    430     sys.stderr.flush()
--> 431 return Popen(args, **popts)

File ~/miniconda3/envs/grass/grass84/etc/python/grass/script/core.py:72, in Popen.__init__(self, args, **kwargs)
     69     si.wShowWindow = subprocess.SW_HIDE
     70     kwargs["startupinfo"] = si
---> 72 subprocess.Popen.__init__(self, args, **kwargs)

File ~/miniconda3/envs/grass/lib/python3.14/subprocess.py:1038, in Popen.__init__(self, args, bufsize, executable, stdin, stdout, stderr, preexec_fn, close_fds, shell, cwd, env, universal_newlines, startupinfo, creationflags, restore_signals, start_new_session, pass_fds, user, group, extra_groups, encoding, errors, text, umask, pipesize, process_group)
   1034         if self.text_mode:
   1035             self.stderr = io.TextIOWrapper(self.stderr,
   1036                     encoding=encoding, errors=errors)
-> 1038     self._execute_child(args, executable, preexec_fn, close_fds,
   1039                         pass_fds, cwd, env,
   1040                         startupinfo, creationflags, shell,
   1041                         p2cread, p2cwrite,
   1042                         c2pread, c2pwrite,
   1043                         errread, errwrite,
   1044                         restore_signals,
   1045                         gid, gids, uid, umask,
   1046                         start_new_session, process_group)
   1047 except:
   1048     # Cleanup if the child failed starting.
   1049     for f in filter(None, (self.stdin, self.stdout, self.stderr)):

File ~/miniconda3/envs/grass/lib/python3.14/subprocess.py:1989, in Popen._execute_child(self, args, executable, preexec_fn, close_fds, pass_fds, cwd, env, startupinfo, creationflags, shell, p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite, restore_signals, gid, gids, uid, umask, start_new_session, process_group)
   1987     err_msg = os.strerror(errno_num)
   1988 if err_filename is not None:
-> 1989     raise child_exception_type(errno_num, err_msg, err_filename)
   1990 else:
   1991     raise child_exception_type(errno_num, err_msg)

FileNotFoundError: [Errno 2] No such file or directory: 'v.buffer'

System description

• version=8.4.2
• date=2025
• revision=9519c048f6
• build_date=2026-01-13
• build_platform=aarch64-apple-darwin20.0.0
• build_off_t_size=8
• libgis_revision=9519c048f6
• libgis_date=2025-11-21T14:02:57+00:00
• proj=9.7.0
• gdal=3.12.1
• geos=
• sqlite=3.51.2
• 3.14.3 | packaged by conda-forge | (main, Feb 9 2026, 22:09:14) [Clang 20.1.8 ]
• 4.2.4 osx-cocoa (phoenix) wxWidgets 3.2.8

[nilason]

I see GEOS version number is missing, v.buffer depends on GEOS, which should be added to https://github.com/conda-forge/grass-feedstock/blob/main/recipe/meta.yaml.

Please, file an identical ticket to https://github.com/conda-forge/grass-feedstock/pulls (or even a PR).

[wenzeslaus]

1. v.buffer should work even without GEOS no?
2. Check if anything else works. Are you missing a session?

[nilason]

• v.buffer should work even without GEOS no?

It doesn't, for quite a while now since e5ae98f.

[baharmon]

2. Check if anything else works. Are you missing a session?

I updated the example to initialize a session. The example was too minimal....
Tested with print(gs.parse_command("g.gisenv", flags="s")).

Yes, everything else I tried so far works.