refactor: code deduplication and simplification

[ndeloof]

Pure refactoring — no functional changes. All existing tests pass.

Changes:

• Extract withBackend() helper in cmd/compose/ to replace repetitive NewComposeService → backend.Foo boilerplate in pause, unpause, kill, start, stop, restart
• Extract optionalTimeout() helper to deduplicate timeout-pointer construction in stop/restart
• Collapse ~18 trivial event-helper one-liners in progress.go to newEvent() calls; keep only functions used ≥3 times or as function values
• Remove redundant package-level wrapper functions in dependencies.go (leaves, roots, getChildren, filterChildren, filterParents) — replaced with method expressions; replace remove(slice, item) with slices.DeleteFunc
• Extract removeResource() helper in down.go to deduplicate the remove-emit pattern shared by removeImage and removeVolume
• Extract forEachContainerConcurrent() in containers.go to deduplicate the errgroup iteration pattern in pause, unpause, kill
• Collapse three identical blocks in resolveSharedNamespaces (NetworkMode/Ipc/Pid) into a resolve closure
• Inline containers.forEach (only 1 remaining call site); add mutation comment to sorted(); replace hasConfigHashLabel() with api.ConfigHashLabel directly; add labelFilter() factory for label filters; remove unused Set.Clear and Set.Union

[Copilot]

Pull request overview

Refactors Compose CLI/service code to reduce duplication by extracting shared helpers and inlining/removing trivial wrappers, while keeping behavior the same.

Changes:

• Added shared helpers in cmd/compose/ (withBackend, optionalTimeout) and pkg/compose/ (forEachContainerConcurrent, removeResource, labelFilter) to deduplicate common patterns.
• Simplified progress/event emission by collapsing many one-off event helper functions into direct newEvent(...) calls.
• Removed unused utilities/wrappers (graph traversal wrapper fns; utils.Set methods/tests) and updated call sites/tests accordingly.

Reviewed changes

Copilot reviewed 24 out of 24 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
pkg/utils/set_test.go	Removes the Union unit test and its now-unused import.
pkg/utils/set.go	Removes unused Set methods and repositions RemoveAll.
pkg/compose/restart.go	Switches to newEvent(...) for restart progress events.
pkg/compose/remove.go	Simplifies iteration over stopped containers; adds cyclo suppression annotation.
pkg/compose/pull.go	Replaces pull progress helpers with newEvent(...) calls.
pkg/compose/ps_test.go	Updates label filtering to use api.ConfigHashLabel directly.
pkg/compose/progress.go	Collapses many trivial event helper wrappers into newEvent(...); keeps function-value helpers.
pkg/compose/pause.go	Uses forEachContainerConcurrent to deduplicate pause/unpause concurrency pattern.
pkg/compose/monitor.go	Uses api.ConfigHashLabel directly (removes wrapper indirection).
pkg/compose/logs_test.go	Updates label filtering to use api.ConfigHashLabel directly.
pkg/compose/kill_test.go	Updates label filtering to use api.ConfigHashLabel directly.
pkg/compose/kill.go	Uses forEachContainerConcurrent and newEvent(...) for kill progress events.
pkg/compose/filters.go	Introduces labelFilter(...) and removes redundant hasConfigHashLabel().
pkg/compose/down.go	Extracts removeResource(...) helper and switches stop events to newEvent(...).
pkg/compose/dependencies.go	Removes redundant wrapper functions via method expressions; replaces custom slice remove with slices.DeleteFunc.
pkg/compose/convergence_test.go	Updates label filtering to use api.ConfigHashLabel directly.
pkg/compose/convergence.go	Replaces several progress helpers with newEvent(...); refactors shared-namespace resolution via closure.
pkg/compose/containers.go	Adds forEachContainerConcurrent; documents sorted() as in-place mutation; uses api.ConfigHashLabel directly.
cmd/compose/stop.go	Uses withBackend(...) and optionalTimeout(...) to deduplicate backend/timeout boilerplate.
cmd/compose/start.go	Uses withBackend(...) to deduplicate backend creation boilerplate.
cmd/compose/restart.go	Uses withBackend(...) and optionalTimeout(...) to deduplicate backend/timeout boilerplate.
cmd/compose/pause.go	Uses withBackend(...) to deduplicate backend creation boilerplate.
cmd/compose/kill.go	Uses withBackend(...) to deduplicate backend creation boilerplate.
cmd/compose/backend.go	Adds new shared backend/timeout helper functions.

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[Copilot]

Set is an exported type, and this change removes exported methods (Clear, Union). Even if they’re unused internally, this is a compile-time breaking API change for any downstream consumers importing pkg/utils. Consider keeping these methods as thin wrappers (potentially marked deprecated) or moving Set to an internal/ package if it’s not meant to be part of the public API.

[ndeloof]

Restored. Both Clear and Union are back as thin wrappers with // Deprecated: godoc comments, preserving API compatibility for any downstream consumers. Fixed in the latest commit.

[Copilot]

resource is computed as "Image "+service.Image, but the progress events re-create the same string literal. Using the resource variable for the newEvent calls would avoid duplication and guarantees the event IDs stay consistent if the formatting ever changes.

[ndeloof]

Fixed — the newEvent calls now use the already-computed resource variable instead of re-constructing the string literal. Fixed in the latest commit.

[codecov]

Codecov Report

❌ Patch coverage is 82.51748% with 25 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
cmd/compose/pause.go	50.00%	5 Missing ⚠️
pkg/compose/pause.go	50.00%	5 Missing ⚠️
pkg/utils/set.go	16.66%	4 Missing and 1 partial ⚠️
cmd/compose/backend.go	60.00%	3 Missing and 1 partial ⚠️
pkg/compose/kill.go	70.00%	2 Missing and 1 partial ⚠️
pkg/compose/convergence.go	86.66%	1 Missing and 1 partial ⚠️
pkg/compose/down.go	94.11%	1 Missing ⚠️

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