The prime step uses the install dir when creating a list of migrateable filesets
Metadata
Current evaluation
Prime can fail after stage exclusions because its fileset is computed from install rather than staged content; the proposed fix is blocked by undefined overlay-cleaning semantics.
Suggested action: keep open
Reason: The current prime implementation still computes its fileset from part_install_dir while copying from stage_dir, matching the reported CopyFileNotFound failure. A maintainer confirmed that switching to stage_dir changes overlay-cleaning behavior and breaks overlay integration tests, so the valid bug remains open pending definition and testing of overlay semantics.
Evaluated by: mr-cal-bot
Impact:
58
Quick Win:
10
Complexity:
76
Confidence:
96
Actionability:
70
Issue body
### Bug Description
craft-parts will fail if a `stage` and `prime` are defined for a part and `stage` removes a file.
This can be fixed by changing [this line](https://github.com/canonical/craft-parts/blob/cdcc9dbc76e5fcf352a9744f1d1c74cfab6c15e5/craft_parts/executor/step_handler.py#L243):
```diff
diff --git a/craft_parts/executor/step_handler.py b/craft_parts/executor/step_handler.py
index c88b409..29e6ef8 100644
--- a/craft_parts/executor/step_handler.py
+++ b/craft_parts/executor/step_handler.py
@@ -240,7 +240,7 @@ class StepHandler:
else:
files, dirs = filesets.migratable_filesets(
- prime_fileset, str(self._part.part_install_dir)
+ prime_fileset, str(self._part.stage_dir)
)
files, dirs = migrate_files(
files=files,
```
I don't know if this is on purpose, but it has been like this since it was first added to craft-parts [here](https://github.com/canonical/craft-parts/pull/59/files#diff-8b05be16f7434251a31499a62b63d4f9f2962efd02f3896a9308cbc3ab034dcfR157).
source: https://github.com/canonical/snapcraft/issues/4835 from @dilyn-corner
### To Reproduce
1. Create the filetree:
```
└── src
└── foo
└── bar
├── baz
├── buzz
└── fizz
```
2. Create and run the python script:
```python
import logging
import yaml
import craft_parts
from craft_parts import LifecycleManager, Step
logging.basicConfig(level=logging.DEBUG)
parts_yaml = """
parts:
hello:
plugin: dump
source: src/
stage:
- -foo/bar/baz
prime:
- foo/bar
"""
parts = yaml.safe_load(parts_yaml)
lcm = LifecycleManager(
parts,
application_name="example",
cache_dir=".",
)
with lcm.action_executor() as aex:
aex.execute(lcm.plan(Step.PRIME))
```
### part yaml
_No response_
### Relevant log output
```shell
DEBUG:craft_parts.utils.os_utils:is_snap: False, SNAP_NAME set to None
DEBUG:craft_parts.infos:Setting target machine to x86_64
DEBUG:craft_parts.sources.local_source:ignore patterns: []
INFO:craft_parts.executor.executor:Installing build-packages
DEBUG:craft_parts.executor.executor:verify plugin environment for part 'hello'
DEBUG:craft_parts.sequencer:process hello:1
DEBUG:craft_parts.sequencer:add action hello:1(0)
DEBUG:craft_parts.sequencer:process hello:3
DEBUG:craft_parts.sequencer:add action hello:3(0)
DEBUG:craft_parts.sequencer:process hello:4
DEBUG:craft_parts.sequencer:add action hello:4(0)
DEBUG:craft_parts.sequencer:process hello:5
DEBUG:craft_parts.sequencer:add action hello:5(0)
DEBUG:craft_parts.executor.executor:execute action hello:Action(part_name='hello', step=Step.PULL, action_type=ActionType.RUN, reason=None, project_vars=None, properties=ActionProperties(changed_files=None, changed_dirs=None))
DEBUG:craft_parts.executor.executor:execute action hello:Action(part_name='hello', step=Step.BUILD, action_type=ActionType.RUN, reason=None, project_vars=None, properties=ActionProperties(changed_files=None, changed_dirs=None))
DEBUG:craft_parts.state_manager.states:load state file: /home/developer/dev/craft-parts-examples/prime-fileset-from-stage-dir/parts/hello/state/pull
DEBUG:craft_parts.executor.part_handler:remove directory /home/developer/dev/craft-parts-examples/prime-fileset-from-stage-dir/parts/hello/build
DEBUG:craft_parts.executor.step_handler:Executing PosixPath('/home/developer/dev/craft-parts-examples/prime-fileset-from-stage-dir/parts/hello/run/build.sh')
+ cp --archive --link --no-dereference . /home/developer/dev/craft-parts-examples/prime-fileset-from-stage-dir/parts/hello/install
DEBUG:urllib3.connectionpool:http://localhost:None "GET /v2/snaps HTTP/1.1" 200 None
DEBUG:craft_parts.executor.executor:execute action hello:Action(part_name='hello', step=Step.STAGE, action_type=ActionType.RUN, reason=None, project_vars=None, properties=ActionProperties(changed_files=None, changed_dirs=None))
DEBUG:craft_parts.executor.executor:execute action hello:Action(part_name='hello', step=Step.PRIME, action_type=ActionType.RUN, reason=None, project_vars=None, properties=ActionProperties(changed_files=None, changed_dirs=None))
Traceback (most recent call last):
File "/home/developer/dev/craft-parts/craft_parts/utils/file_utils.py", line 141, in link
os.link(source_path, destination, follow_symlinks=False)
FileNotFoundError: [Errno 2] No such file or directory: '/home/developer/dev/craft-parts-examples/prime-fileset-from-stage-dir/stage/foo/bar/baz' -> '/home/developer/dev/craft-parts-examples/prime-fileset-from-stage-dir/prime/foo/bar/baz'
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/home/developer/dev/craft-parts-examples/prime-fileset-from-stage-dir/main.py", line 29, in <module>
aex.execute(lcm.plan(Step.PRIME))
File "/home/developer/dev/craft-parts/craft_parts/executor/executor.py", line 327, in execute
self._executor.execute(actions, stdout=stdout, stderr=stderr)
File "/home/developer/dev/craft-parts/craft_parts/executor/executor.py", line 137, in execute
self._run_action(act, stdout=stdout, stderr=stderr)
File "/home/developer/dev/craft-parts/craft_parts/executor/executor.py", line 214, in _run_action
handler.run_action(action, stdout=stdout, stderr=stderr)
File "/home/developer/dev/craft-parts/craft_parts/executor/part_handler.py", line 170, in run_action
state = handler(step_info, stdout=stdout, stderr=stderr)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/developer/dev/craft-parts/craft_parts/executor/part_handler.py", line 407, in _run_prime
contents = self._run_step(
^^^^^^^^^^^^^^^
File "/home/developer/dev/craft-parts/craft_parts/executor/part_handler.py", line 491, in _run_step
return step_handler.run_builtin()
^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/developer/dev/craft-parts/craft_parts/executor/step_handler.py", line 108, in run_builtin
return handler()
^^^^^^^^^
File "/home/developer/dev/craft-parts/craft_parts/executor/step_handler.py", line 245, in _builtin_prime
files, dirs = migrate_files(
^^^^^^^^^^^^^^
File "/home/developer/dev/craft-parts/craft_parts/executor/migration.py", line 123, in migrate_files
file_utils.link_or_copy(
File "/home/developer/dev/craft-parts/craft_parts/utils/file_utils.py", line 98, in link_or_copy
link(source, destination, follow_symlinks=follow_symlinks)
File "/home/developer/dev/craft-parts/craft_parts/utils/file_utils.py", line 143, in link
raise errors.CopyFileNotFound(source) from err
craft_parts.errors.CopyFileNotFound: Failed to copy '/home/developer/dev/craft-parts-examples/prime-fileset-from-stage-dir/stage/foo/bar/baz': no such file or directory.
```
Evaluation history
| Date | Model | Scores | Action | Summary |
|---|---|---|---|---|
| stealth/space-bunny-alpha |
Impact:
58
Quick Win:
10
Complexity:
76
Confidence:
96
Actionability:
70
|
keep open | Prime can fail after stage exclusions because its fileset is computed from install rather than staged content; the proposed fix is blocked by undefined overlay-cleaning semantics. | |
| qwen/qwen3.6-35b-a3b |
Impact:
60
Quick Win:
10
Complexity:
60
Confidence:
70
Actionability:
40
|
keep open | Prime step fails when stage excludes files, using install dir instead of stage dir for migratable filesets. Blocked on overlay cleaning documentation. | |
| qwen/qwen3.8-27b |
Impact:
50
Quick Win:
14
Staleness:
58
Complexity:
72
Confidence:
82
Support Request:
0
|
keep open | craft-parts prime step computes migratable filesets from the install dir instead of the stage dir, failing when stage removes a file prime includes. A one-line fix was proposed but breaks overlay cleaning tests; blocked on defining overlay cleaning semantics. | |
| qwen/qwen3.6-35b-a3b |
Staleness:
75
Complexity:
85
Confidence:
85
Support Request:
0
|
keep open | Bug where prime step incorrectly uses install dir instead of stage dir for fileset migration, causing failures when stage removes files. Currently blocked on defining overlay cleaning behavior after a proposed fix broke integration tests. | |
| qwen3.6-35b-a3b-mtp-q6 |
Staleness:
75
Complexity:
80
Confidence:
85
Support Request:
10
|
keep open | Bug where prime step incorrectly uses install dir for migratable filesets, causing failures when stage removes files. Currently blocked by maintainer pending documentation of overlay cleaning behavior. |
Update history
No update history recorded yet.
Related work
-
Related To:
canonical/snapcraft#4835
(confidence 100%)
Explicitly cited as the source of the report.
-
Related To:
canonical/craft-parts#59
(confidence 98%)
The pull request that originally introduced the install-dir-based fileset calculation.
Related issues
No related issues found above the similarity threshold.