feat: handle snap components in stage-snaps

Metadata

Project: craft-parts
Number: #1604
Type: pull request
State: open
Author: bepri
Labels: —
Created: 2026-06-02 07:22 PM UTC
Updated: 2026-08-25 04:30 PM UTC
Closed: —

Current evaluation

Adds snap component support to stage-snaps (unpacking component trees, SNAP_COMPONENTS). Marked draft by mr-cal pending snapd UX decisions; 3 unresolved review threads and 5 CI jobs still failing.

Suggested action: keep open

Reason: mr-cal explicitly parked this work: "Marking as a draft so we don't accidentally merge while we reconsider how to organize components" and later "We should wait to see how that progresses before this PR continues", citing canonical/snapd#17435 ($SNAP_COMPONENTS support) and Jira PF-6858 for remaining UX gaps. This is an intentional hold on external upstream decisions, not abandonment — only 38 days since the last comment — so close_stale does not apply, and the author (bepri) plus two approvals show the work is still live. Merging now is not advisable: 3 review comments remain unresolved and 5 CI jobs fail (test-common on both min-deps and ubuntu-22.04-arm, two s390x/edge suites, and Security scan / OSV-scanner), so actionability is low despite the approved status. The change itself (+627/-60, 13 files) touches the core SnapSource provisioning path in craft_parts/sources/snap_source.py and the executor's _unpack_stage_snaps, so it carries moderate architectural and filesystem-layout review weight.

Evaluated by: mr-cal-bot

Impact: 45 Quick Win: 5 Complexity: 55 Confidence: 86 Actionability: 25

Issue body

- [ ] Have you followed the guidelines for contributing? - [ ] Have you signed the [CLA](http://www.ubuntu.com/legal/contributors/)? - [ ] Have you successfully run `make lint && make test`? - [ ] Have you added an entry to the changelog (`docs/reference/changelog.rst`)? --- When used with Snapcraft, this parts entry: ```yaml parts: my-part: plugin: nil stage-snaps: - test-snap-with-component+comp1+comp2/beta ``` Produced these contents in the unpacked snap: ``` unsquashfs-root ├── hello-app ├── load-comp1 ├── load-comp2 ├── meta │ ├── gui │ └── snap.yaml ├── meta.test-snap-with-component │ ├── gui │ └── snap.yaml └── snap └── test-snap-with-component └── components └── mnt ├── comp1 │ └── 3 │ ├── hello-comp1 │ └── meta │ └── component.yaml └── comp2 └── 3 ├── hello-comp2 └── meta └── component.yaml ``` SNAPCRAFT-1345

Evaluation history

Date	Model	Scores	Action	Summary
2026-10-02 08:11 PM UTC	stealth/space-bunny-alpha	Impact: 45 Quick Win: 5 Complexity: 55 Confidence: 86 Actionability: 25	keep open	Adds snap component support to stage-snaps (unpacking component trees, SNAP_COMPONENTS). Marked draft by mr-cal pending snapd UX decisions; 3 unresolved review threads and 5 CI jobs still failing.
2026-09-24 09:07 PM UTC	stealth/space-bunny-alpha	Impact: 40 Quick Win: 4 Complexity: 65 Confidence: 94 Actionability: 30	keep open	Adds component support to stage-snaps, but is now a draft awaiting snapd UX work; three review threads remain unresolved and five CI checks are failing.
2026-09-05 12:11 AM UTC	qwen3.6-35b-a3b-mtp-q6	Impact: 45 Quick Win: 11 Staleness: 65 Complexity: 75 Confidence: 75	keep open	Handles snap components in stage-snaps. Marked as draft with 2 approvals but 3 unresolved comments. Blocked by pending snapd changes per maintainer feedback.
2026-08-25 04:33 PM UTC	qwen/qwen3.6-35b-a3b	Staleness: 10 Complexity: 65 Confidence: 90	keep open	Implements snap component handling in stage-snaps, reorganizing directory structure and introducing $SNAP_COMPONENTS usage. Currently marked as draft and blocked by upstream snapd changes pending UX improvements.
2026-08-18 07:34 PM UTC	qwen/qwen3.6-35b-a3b	Staleness: 40 Complexity: 60 Confidence: 85	keep open	Adds support for snap components in stage-snaps by restructuring unpacked snap directories. Currently drafted and paused pending upstream snapd integration and architectural review on component layout.
2026-07-22 02:46 PM UTC	qwen/qwen3.6-35b-a3b	Staleness: 45 Complexity: 65 Confidence: 90	keep open	Adds support for snap components in stage-snaps, restructuring unpacked snap contents. Currently marked as draft by a maintainer pausing for architectural reconsideration and feedback collection. CI has failing tests and 20 unresolved comments.
2026-07-10 11:50 AM UTC	qwen3.6-35b-a3b-mtp-q6	Staleness: 45 Complexity: 65 Confidence: 85	keep open	Draft PR adding support for snap components in stage-snaps. Maintainer marked it draft to reconsider component directory organization and gather more feedback from snapd and developers.

Update history

Date	Change
2026-08-25 04:30 PM UTC	updated
2026-08-18 07:30 PM UTC	updated

Related work

Related To: snapcraft#6095 (confidence 88%)
Feature request 'Allow staging snap components'; tracked as implemented by this craft-parts PR and currently on hold pending snapd UX decisions.
Blocked By: snapd#17435 (confidence 80%)
mr-cal states this snapd PR 'is going to give us a good path forward' — it introduces $SNAP_COMPONENTS so staged snap content can find its components.

Related issues

Issue	Project	State	Summary	Similarity
#6095 Allow staging snap components	snapcraft	open	Feature request to support snap components in stage-snaps (snap+component syntax). Triaged as feasible; implementation lives upstream in craft-parts PR #1604, currently on hold pending snapd UX decisions on component access/management.	80%
#1805214 stage-snaps	snapcraft (launchpad)	closed	Feature request for a stage-snaps keyword (unpack a snap's content into the snap being built, like stage-packages) was implemented and merged in canonical/snapcraft#2468 (commit 0983e4063), then shipped in the 3.2 release; follow-up fixes in #2525 and #3211.	72%