`CraftSpreadYaml` should accept the `environment` key

[lczyk]

What needs to get done

CraftSpreadYaml model at craft_application/models/spread.py does not accept the environment key which limits the ways in which the spread test can be set up.

specific example

in chisel-releases we use the environment key to add an entry to the PATH with extra libraries. there we run the tests with spread directly, and all is great.

i've been working on the rust-rock recently, and i wanted to implement this kind of pattern (which would eventually hopefully be adopted by into the rocks-template), however, when trying it out, the test fails in the cli (relevant logs pasted below in case the cli logs are no longer available). i've tracked the issue down to the fact that the builder calls rockcraft test rather than using spread (called by the oci-factory). from there + actually looking at the python stacktrace, i've narrowed it down to CraftSpreadYaml being self-proclaimedly only a simplified version.

 2025-09-26 14:43:15.904 rockcraft internal error: 1 validation error for CraftSpreadYaml
2025-09-26 14:43:15.904 environment
2025-09-26 14:43:15.904   Extra inputs are not permitted [type=extra_forbidden, input_value={'SHARED_LIBRARIES': '$PR...PATH:$SHARED_LIBRARIES'}, input_type=dict]
2025-09-26 14:43:15.904     For further information visit https://errors.pydantic.dev/2.11/v/extra_forbidden
2025-09-26 14:43:15.911 Traceback (most recent call last):
2025-09-26 14:43:15.912   File "/snap/rockcraft/3592/lib/python3.12/site-packages/craft_application/application.py", line 650, in run
2025-09-26 14:43:15.912     return_code = self._run_inner()
2025-09-26 14:43:15.912                   ^^^^^^^^^^^^^^^^^
2025-09-26 14:43:15.912   File "/snap/rockcraft/3592/lib/python3.12/site-packages/craft_application/application.py", line 627, in _run_inner
2025-09-26 14:43:15.912     return_code = dispatcher.run() or os.EX_OK
2025-09-26 14:43:15.912                   ^^^^^^^^^^^^^^^^
2025-09-26 14:43:15.912   File "/snap/rockcraft/3592/lib/python3.12/site-packages/craft_cli/dispatcher.py", line 564, in run
2025-09-26 14:43:15.912     return self._loaded_command.run(self._parsed_command_args)
2025-09-26 14:43:15.912            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
2025-09-26 14:43:15.912   File "/snap/rockcraft/3592/lib/python3.12/site-packages/craft_application/commands/base.py", line 200, in run
2025-09-26 14:43:15.912     result = self._run(parsed_args, **kwargs) or result
2025-09-26 14:43:15.912              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
2025-09-26 14:43:15.912   File "/snap/rockcraft/3592/lib/python3.12/site-packages/craft_application/commands/lifecycle.py", line 684, in _run
2025-09-26 14:43:15.912     testing_service.test(
2025-09-26 14:43:15.912   File "/snap/rockcraft/3592/lib/python3.12/site-packages/craft_application/services/testing.py", line 69, in test
2025-09-26 14:43:15.912     self.process_spread_yaml(temp_spread_file, pack_state)
2025-09-26 14:43:15.912   File "/snap/rockcraft/3592/lib/python3.12/site-packages/craft_application/services/testing.py", line 108, in process_spread_yaml
2025-09-26 14:43:15.912     simple = models.CraftSpreadYaml.unmarshal(data)
2025-09-26 14:43:15.912              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
2025-09-26 14:43:15.912   File "/snap/rockcraft/3592/lib/python3.12/site-packages/craft_application/models/base.py", line 64, in unmarshal
2025-09-26 14:43:15.913     return cls.model_validate(data)
2025-09-26 14:43:15.913            ^^^^^^^^^^^^^^^^^^^^^^^^
2025-09-26 14:43:15.913   File "/snap/rockcraft/3592/lib/python3.12/site-packages/pydantic/main.py", line 705, in model_validate
2025-09-26 14:43:15.913     return cls.__pydantic_validator__.validate_python(
2025-09-26 14:43:15.913            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
2025-09-26 14:43:15.913 pydantic_core._pydantic_core.ValidationError: 1 validation error for CraftSpreadYaml
2025-09-26 14:43:15.913 environment
2025-09-26 14:43:15.913   Extra inputs are not permitted [type=extra_forbidden, input_value={'SHARED_LIBRARIES': '$PR...PATH:$SHARED_LIBRARIES'}, input_type=dict]
2025-09-26 14:43:15.913     For further information visit https://errors.pydantic.dev/2.11/v/extra_forbidden
2025-09-26 14:43:15.913 Full execution log: '/home/ubuntu/.local/state/rockcraft/log/rockcraft-20250926-144007.309280.log'

Why it needs to get done

it would be really great if this functionality would be added so we can bump the craft_application version in rockcraft and configure our tests better. hope it's not tricky and that i've diagnosed the issue correctly.

[lengau]

Thanks for the report!

Tagging @cmatsuoka regarding whether including this will be reasonable. (Implementation is trivial — deciding whether this is something we want to include is nontrivial!)

[lczyk]

turns out that this works as expected btw, so actually much less pressing (although the "global" environment would still be nice)