Steps to reproduce

This can be reproduced with the following config_scopes.py script:

# config_scopes.py
import spack.config
import spack.environment

print(f"BEFORE: {', '.join(spack.config.CONFIG.scopes)}\n")
with spack.environment.read("test"):
    print(f"test-env: {', '.join(spack.config.CONFIG.scopes)}\n")
print(f"AFTER: {', '.join(spack.config.CONFIG.scopes)}\n")

Running the following commands:

$ spack env create test
$ spack env activate --temp
$ spack python config_scopes.py

Error message

No error message, but the output:

$ spack python try.py 
BEFORE: _builtin, defaults, defaults/linux, system, system/linux, site, site/linux, user, user/linux, env:/tmp/spack-usl4w43m, command_line

test-env: _builtin, defaults, defaults/linux, system, system/linux, site, site/linux, user, user/linux, env:/tmp/spack-usl4w43m, env:test, command_line

AFTER: _builtin, defaults, defaults/linux, system, system/linux, site, site/linux, user, user/linux, env:/tmp/spack-usl4w43m, command_line

shows that within the context manager two environment scopes are active.

Information on your system

• Spack: 1.0.0.dev0 (9e508b0)
• Python: 3.13.0
• Platform: linux-ubuntu20.04-icelake

General information

• I have run spack debug report and reported the version of Spack/Python/Platform
• I have searched the issues of this repo and believe this is not a duplicate
• I have run the failing commands in debug mode and reported the output