Non-list `build-for` values are no longer allowed
Metadata
Current evaluation
snapcraft 8.13.0 rejects valid non-list build-for values (e.g. build-for: amd64) in core22 platforms, raising an unhelpful RuntimeError instead of treating the string as a single-entry list. Triaged, open, no fix yet.
Suggested action: keep open
Reason: The issue is a genuine regression: the Architecture model documents that a string build-for is parsed into a single-entry list at runtime, but get_build_for() at project.py:2254 only handles isinstance(build_for, list), so a scalar value falls through to the RuntimeError. The label 'Status: Triaged' and the linked internal ticket SNAPCRAFT-1253 confirm maintainer acknowledgement, so it should stay open until a fix lands.
Impact:
50
Quick Win:
30.0
Staleness:
55
Complexity:
40
Confidence:
70
Support Request:
5
Issue body
### Bug Description
The following (valid) form of a platform no longer works:
```yaml
platforms:
p:
- build-on: [amd64]
build-for: amd64
```
It also gives an incredibly unhelpful error message (see below)
### To Reproduce
Attempt to run `snapcraft pull --enable-experimental-plugins` on the test at `tests/spread/plugins/craft-parts/kernel`.
### Environment
snapcraft 8.13.0
### snapcraft.yaml
```yaml
see above
```
### Relevant log output
```shell
Traceback (most recent call last):
File "/snap/snapcraft/x1/lib/python3.12/site-packages/snapcraft/application.py", line 472, in main
return app.run()
^^^^^^^^^
File "/snap/snapcraft/x1/lib/python3.12/site-packages/craft_application/application.py", line 663, in run
return_code = self._run_inner()
^^^^^^^^^^^^^^^^^
File "/snap/snapcraft/x1/lib/python3.12/site-packages/snapcraft/application.py", line 183, in _run_inner
return_code = super()._run_inner()
^^^^^^^^^^^^^^^^^^^^
File "/snap/snapcraft/x1/lib/python3.12/site-packages/craft_application/application.py", line 606, in _run_inner
dispatcher = self._get_dispatcher()
^^^^^^^^^^^^^^^^^^^^^^
File "/snap/snapcraft/x1/lib/python3.12/site-packages/snapcraft/application.py", line 410, in _get_dispatcher
self._check_for_classic_fallback()
File "/snap/snapcraft/x1/lib/python3.12/site-packages/snapcraft/application.py", line 322, in _check_for_classic_fallback
raise errors.ClassicFallback()
snapcraft.errors.ClassicFallback
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/snap/snapcraft/x1/bin/snapcraft", line 7, in <module>
sys.exit(main())
^^^^^^
File "/snap/snapcraft/x1/lib/python3.12/site-packages/snapcraft/application.py", line 475, in main
return cli.run()
^^^^^^^^^
File "/snap/snapcraft/x1/lib/python3.12/site-packages/snapcraft/cli.py", line 259, in run
_run_dispatcher(dispatcher, global_args)
File "/snap/snapcraft/x1/lib/python3.12/site-packages/snapcraft/cli.py", line 232, in _run_dispatcher
dispatcher.run()
File "/snap/snapcraft/x1/lib/python3.12/site-packages/craft_cli/dispatcher.py", line 564, in run
return self._loaded_command.run(self._parsed_command_args)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/snap/snapcraft/x1/lib/python3.12/site-packages/snapcraft/commands/core22/lifecycle.py", line 268, in run
super().run(parsed_args)
File "/snap/snapcraft/x1/lib/python3.12/site-packages/snapcraft/commands/core22/lifecycle.py", line 141, in run
parts_lifecycle.run(self.name, parsed_args)
File "/snap/snapcraft/x1/lib/python3.12/site-packages/snapcraft/parts/lifecycle.py", line 105, in run
_run_command(
File "/snap/snapcraft/x1/lib/python3.12/site-packages/snapcraft/parts/lifecycle.py", line 141, in _run_command
_run_in_provider(project, command_name, parsed_args)
File "/snap/snapcraft/x1/lib/python3.12/site-packages/snapcraft/parts/lifecycle.py", line 475, in _run_in_provider
cmd.append(project.get_build_for())
^^^^^^^^^^^^^^^^^^^^^^^
File "/snap/snapcraft/x1/lib/python3.12/site-packages/snapcraft/models/project.py", line 2214, in get_build_for
raise RuntimeError("cannot determine build-for architecture")
RuntimeError: cannot determine build-for architecture
```
### Additional context
_No response_
Evaluation history
| Date | Model | Scores | Action | Summary |
|---|---|---|---|---|
| qwen/qwen3.8-27b |
Impact:
50
Quick Win:
30.0
Staleness:
55
Complexity:
40
Confidence:
70
Support Request:
5
|
keep open | snapcraft 8.13.0 rejects valid non-list build-for values (e.g. build-for: amd64) in core22 platforms, raising an unhelpful RuntimeError instead of treating the string as a single-entry list. Triaged, open, no fix yet. | |
| qwen/qwen3.6-35b-a3b |
Staleness:
75
Complexity:
45
Confidence:
80
Support Request:
10
|
keep open | Bug report stating non-list build-for values in snapcraft.yaml are rejected with an unhelpful error. Labeled as triaged but inactive for 264 days with no maintainer follow-up. | |
| qwen3.6-35b-a3b-mtp-q6 |
Staleness:
85
Complexity:
45
Confidence:
75
Support Request:
10
|
keep open | Regression in snapcraft 8.13.0 where single-string build-for values are rejected, causing a RuntimeError. Issue is triaged but has seen no maintainer activity in 250 days. | |
| qwen3.6-35b-a3b-mtp-q6 |
Staleness:
75
Complexity:
30
Confidence:
75
Support Request:
10
|
keep open | Snapcraft rejects valid single-value build-for platform configurations with an unhelpful error. The issue is triaged but has been inactive for over seven months and awaits a fix. |
Update history
No update history recorded yet.
Related work
-
Related To:
snapcraft/snapcraft#5043
(confidence 60%)
Commit 19699c1b8 'fix: use correct type for build-on and build-for in build plans' touched the same type-handling area for build-on/build-for, likely where the list-only assumption was introduced.
Related issues
| Issue | Project | State | Summary | Similarity |
|---|---|---|---|---|
| #4881 remote build: fails if `--platform` or `--build-for` are passed with no `platforms` or `architectures` defined | snapcraft | closed | Closed pending implementation per defined scope: restrict --platform/--build-for flags to projects without explicit platform definitions and block their use for core22 snaps. Tracked in Jira CRAFT-3070. | |
| #5435 remote build: deprecate `--build-for` | snapcraft | open | Deprecate --build-for in snapcraft remote-build to align with Craft Application and other craft tools. Triaged by maintainer who confirmed it can ship in a minor release, but blocked by Launchpad's new build farm migration for --platform support. Code confirms --build-for is still active without deprecation warning. |