Align container list format with Docker specifications

[ggarzia-MSFT]

Summary of the Pull Request

Brings wslc container list to output parity with docker container list, for both the table and --format json. This was the largest remaining gap found in a systematic wslc-vs-docker output comparison across 81 command pairs.

Three changes:

• Table — column order now matches docker (CONTAINER ID / IMAGE / COMMAND / CREATED / STATUS / PORTS / NAMES), adding the missing COMMAND column and moving NAMES last. STATUS now reports the runtime's own description (Up 5 minutes, Exited (0) 2 hours ago) instead of a locally derived string.
• --format json — emits docker's 16-key shape, with every value a pre-rendered string apart from the nested Platform object. This matches the convention already used by wslc image list and wslc network list.
• --quiet — truncates to docker's 12-character short ID, with --no-trunc for the full ID.

The service now supplies the additional data docker reports (Command, Status, Labels, Networks, Mounts, LocalVolumes), so WSLCContainerEntry gains those fields.

PR Checklist

• Closes: Link to issue #xxx
• Communication: I've discussed this with core contributors already. If work hasn't been agreed, this work might be rejected
• Tests: Added/updated if needed and all pass
• Localization: All end user facing strings can be localized
• Dev docs: Added/updated if needed
• Documentation updated: If checked, please file a pull request on our docs repo and link it here: #xxx

Detailed Description of the Pull Request / Additional comments

JSON output is a breaking change

container list --format json previously emitted a raw-data view of the internal model:

{"Id":"<64 chars>","Name":"web","Image":"alpine:3.20","State":1,"StateChangedAt":1755543210,"CreatedAt":1755543200,"Ports":[...]}

It now emits docker's shape:

{"Command":"\"sleep 3600\"","CreatedAt":"2026-08-18 12:06:50 -0700 PDT","HealthStatus":"none","ID":"0dba0f244a97","Image":"alpine:3.20","Labels":"...","LocalVolumes":"0","Mounts":"","Names":"web","Networks":"bridge","Platform":{"architecture":"amd64","os":"linux"},"Ports":"","RunningFor":"28 seconds ago","Size":"0B","State":"running","Status":"Up 27 seconds"}

Notably Id → ID, Name → Names, integer timestamps → formatted strings, the Ports array → a rendered string, and IDs truncated unless --no-trunc . This mirrors the rename already made deliberately for network list, and is what makes docker-oriented tooling and Go-template-style consumers work unchanged.

Design

 ToContainerOutput() builds a single  ContainerOutputInformation  consumed by both the table and the JSON renderer, so the two cannot drift. This is the same pattern as  ToImageOutput() /  ImageOutputInformation .

 ContainerOutputInformation  is kept separate from  ContainerInformation  on purpose: the former mirrors docker's all-string output shape, the latter mirrors the service's native types.

Container state names exist in two forms —  ContainerStateName() returns invariant English because it feeds the machine-readable JSON, while  LocalizedContainerStateName() is the display form used by the table.

Validation Steps Performed

• Added WSLCE2E_Container_List_TableFormat_MatchesDockerColumnOrder , asserting the header row matches docker's column order.
• Added WSLCE2E_Container_List_JsonFormat_MatchesDockerShape , asserting the exact 16-key set, that every value is a string apart from Platform , and that IDs are 12 characters by default.
• Rewrote the --quiet E2E test to cover both truncated and --no-trunc  output.
• Added 10 unit tests for  FormatCommand  (quoting, escaping, 20-character shortening, code-point counting for multi-byte input) and  FormatStatus  (runtime description preferred, fallback when empty).
• Migrated the ~12 existing E2E call sites and the shared  ListAllContainers() helper to the new JSON shape.
• Expected output was validated against real docker container list output captured from a parity harness run covering 81 wslc/docker command pairs.
•  clang-format 19.1.5 clean across all files changed on the branch.

[Copilot]

Pull request overview

This PR updates wslc container list to better match docker container list output, including table column order, --format json shape, and --quiet truncation behavior. It also extends the service/container models to provide additional Docker-parity fields needed by both the table and JSON views.

Changes:

• Reworks container list rendering to use a shared ContainerOutputInformation (table + NDJSON) with Docker-aligned fields, and updates --quiet/--no-trunc behavior.
• Extends the service and schema models to carry Docker-reported container metadata (e.g., Command, Status, Labels, Networks, Mounts, LocalVolumes).
• Updates and adds unit/E2E tests to validate the new table layout, JSON shape, and truncation rules.

Reviewed changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
test/windows/wslc/WSLCCLIContainerCommandUnitTests.cpp	Adds unit tests for FormatCommand and FormatStatus.
test/windows/wslc/e2e/WSLCE2EHelpers.h	Updates helper API to return ContainerOutputInformation.
test/windows/wslc/e2e/WSLCE2EHelpers.cpp	Updates helpers for new JSON shape/field names and status matching.
test/windows/wslc/e2e/WSLCE2EContainerListTests.cpp	Adds/updates E2E coverage for Docker-aligned table headers, JSON shape, and ID truncation.
src/windows/wslcsession/WSLCSession.cpp	Populates newly added service-side WSLCContainerEntry fields from Docker data.
src/windows/wslc/tasks/ContainerTasks.cpp	Implements Docker-shape NDJSON and new table column order via ToContainerOutput().
src/windows/wslc/services/ContainerService.h	Adds APIs for invariant state names and Docker-like command/status formatting.
src/windows/wslc/services/ContainerService.cpp	Implements FormatCommand, FormatStatus, and splits invariant vs localized state naming.
src/windows/wslc/services/ContainerModel.h	Adds ContainerOutputInformation and extends ContainerInformation to carry new fields.
src/windows/service/inc/wslc.idl	Extends WSLCContainerEntry and introduces max-length constants for new fields.
src/windows/inc/docker_schema.h	Extends docker schema parsing to include Command and Status.
localization/strings/en-US/Resources.resw	Adds table headers (COMMAND, NAMES) and container state strings.

Suppressed comments (1)

src/windows/wslcsession/WSLCSession.cpp:2603

• These strncpy_s calls only throw when the return value is EINVAL, but other non-zero return values would be ignored. Since truncation is expected with _TRUNCATE (STRUNCATE), it’s safer to throw on anything that is neither 0 nor STRUNCATE.

        THROW_HR_IF(E_UNEXPECTED, strncpy_s(output[index].Labels, std::size(output[index].Labels), joinedLabels.c_str(), _TRUNCATE) == EINVAL);
        THROW_HR_IF(E_UNEXPECTED, strncpy_s(output[index].Networks, std::size(output[index].Networks), joinedNetworks.c_str(), _TRUNCATE) == EINVAL);
        THROW_HR_IF(E_UNEXPECTED, strncpy_s(output[index].Mounts, std::size(output[index].Mounts), joinedMounts.c_str(), _TRUNCATE) == EINVAL);

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[Copilot]

Pull request overview

Copilot reviewed 12 out of 12 changed files in this pull request and generated no new comments.

[Copilot]

Pull request overview

Copilot reviewed 12 out of 12 changed files in this pull request and generated no new comments.

Suppressed comments (1)

src/windows/service/inc/wslc.idl:390

• WSLCContainerEntry now includes several large fixed-size char buffers (e.g. 4K Command/Labels/Mounts). Because ListContainers returns an array of WSLCContainerEntry over COM/RPC, this significantly increases the marshaled payload and client-side allocation per entry even when the strings are short, which can slow down container list (and any callers) for large container counts.

Consider switching these fields to variable-length marshaled strings (e.g. [string] LPSTR) and allocating per-value, or gating the extended fields behind an option flag (so --quiet/minimal listings don’t pay the cost).

    char Command[WSLC_MAX_CONTAINER_COMMAND_LENGTH + 1];
    char Status[WSLC_MAX_CONTAINER_STATUS_LENGTH + 1];
    char Labels[WSLC_MAX_CONTAINER_LABELS_LENGTH + 1];
    char Networks[WSLC_MAX_CONTAINER_NETWORKS_LENGTH + 1];
    char Mounts[WSLC_MAX_CONTAINER_MOUNTS_LENGTH + 1];

[Copilot]

Pull request overview

Copilot reviewed 12 out of 12 changed files in this pull request and generated no new comments.

Suppressed comments (1)

test/windows/wslc/e2e/WSLCE2EHelpers.cpp:186

• The test assumes the STATUS column always contains Docker-style runtime prefixes (e.g. "Up ", "Exited ("), but ContainerService::FormatStatus has a fallback that can emit plain state strings (e.g. "running", "exited") if the runtime doesn't supply a status description. This can make the test fail even when the container is correctly listed. Consider accepting either the Docker-style prefix or the original logical state string when validating the line.

            const std::wstring message = L"Container '" + containerNameOrId + L"' found in container list output but status '" +
                                         expectedStatus + L"' was not found in the same line";
            VERIFY_ARE_NOT_EQUAL(std::wstring::npos, line.find(expectedStatus), message.c_str());

[Pooja Trivedi (ptrivedi)]

thank you for the changes, a few minor comments

[Copilot]

Pull request overview

Copilot reviewed 15 out of 15 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 15 out of 15 changed files in this pull request and generated no new comments.

Suppressed comments (1)

src/windows/wslcsession/WSLCSession.cpp:2563

• freeStrings assumes every WSLCContainerEntry has pointer fields initialized to nullptr (so CoTaskMemFree(nullptr) is safe), but wil::make_unique_cotaskmem<WSLCContainerEntry[]>(...) does not guarantee zero-initialization. If an exception is thrown before all entries are populated, FreeContainerEntryStrings(output[i]) can attempt to free uninitialized garbage pointers and crash.

Explicitly zero-initialize the allocated array before installing the scope-exit cleanup (or otherwise ensure the pointer members are set to null before any possible throw).

    auto output = wil::make_unique_cotaskmem<WSLCContainerEntry[]>(dockerContainers.size());
    auto freeStrings = wil::scope_exit([&] {
        for (size_t i = 0; i < dockerContainers.size(); ++i)
        {