CLI: Add --mount support for create and run - #41337

src/windows/common/MountSpecParsing.cpp:583

• FormatTmpfsOptions also omits an explicitly provided tmpfs-size=0 by skipping size when the parsed value is 0. If the user passes tmpfs-size=0, that intent should be preserved and forwarded (and kept consistent with existing --tmpfs behavior, which can pass size=0).

    if (mount.TmpfsSizeBytes.has_value() && mount.TmpfsSizeBytes.value() != 0)
    {
        options.emplace_back(std::format("size={}", FormatDockerTmpfsSize(mount.TmpfsSizeBytes.value())));
    }

src/windows/common/MountSpecParsing.cpp:579

• FormatTmpfsOptions drops an explicitly provided tmpfs-mode=0000 because it omits the mode option when the parsed value is 0. That changes user-requested semantics (and differs from --tmpfs, which forwards options verbatim), since mode=0 is a meaningful tmpfs setting.

This issue also appears on line 580 of the same file.

    if (mount.TmpfsMode.has_value() && mount.TmpfsMode.value() != 0)
    {
        options.emplace_back(std::format("mode={:o}", mount.TmpfsMode.value()));
    }

src/windows/common/MountSpecParsing.cpp:14

• New files should use the repository’s single-line copyright header format (// Copyright (C) Microsoft Corporation. All rights reserved.). This file currently uses the older block header style.

/*++

Copyright (c) Microsoft. All rights reserved.

src/windows/common/MountSpecParsing.h:14

• New files should use the repository’s single-line copyright header format (// Copyright (C) Microsoft Corporation. All rights reserved.). This header currently uses the older block header style.

/*++

Copyright (c) Microsoft. All rights reserved.

test/windows/wslc/WSLCCLIMountParserUnitTests.cpp:14

• New files should use the repository’s single-line copyright header format (// Copyright (C) Microsoft Corporation. All rights reserved.). This test file currently uses the older block header style.

/*++

Copyright (c) Microsoft. All rights reserved.

src/windows/common/MountSpecParsing.cpp:159

• Minor typo in the digit set passed to find_last_of: it includes an extra '0' ("01234567890. "), which is confusing to readers even though it likely doesn’t change behavior.

        const auto separator = input.find_last_of("01234567890. ");

src/windows/wslc/arguments/ArgumentValidation.cpp:234

• The mount parser’s ValidationException::Reason() is composed of hard-coded English strings (from MountSpecParsing.cpp) and is surfaced directly to users via WSLCCLI_InvalidMountError. This means a significant portion of the user-facing error text is not localizable, which conflicts with the PR’s stated goal of localized errors for unsupported/invalid mount specs.

            catch (const mount::ValidationException& ex)
            {
                throw ArgumentException(Localization::WSLCCLI_InvalidMountError(value, ex.Reason()));
            }

test/windows/wslc/e2e/WSLCE2EContainerCreateTests.cpp:800

• This test is in the container create suite and is named as a create test, but the command under test is container run. That makes it easy to accidentally miss a create-specific regression (and it’s inconsistent with the other newly added --mount create tests in this section).

        auto result = RunWslc(std::format(
            L"container run --name {} --mount \"type=bind,source={},target=/data\" {} true",
            WslcContainerName,
            source.wstring(),
            AlpineImage.NameAndTag()));

src/windows/common/MountSpecParsing.cpp:363

• --mount type=bind sources are normalized to an absolute path when the user passes . or .\..., but ./... (also a common relative form on Windows in some shells) is not handled and will be rejected as non-absolute later. If relative bind sources are intended to be accepted when explicitly dot-prefixed, this should normalize ./ as well.

            mount.Source = keyValue.Value;
            if (mount.Source == L"." || mount.Source.starts_with(L".\\"))
            {
                std::error_code error;
                auto absolutePath = std::filesystem::absolute(mount.Source, error);
                if (!error)
                {
                    mount.Source = absolutePath.lexically_normal().wstring();
                }

test/windows/wslc/e2e/WSLCE2EContainerCreateTests.cpp:800

• The test name indicates container create, but the command under test uses container run. This makes the intent unclear and can hide create-vs-run behavioral differences. Consider switching this command to container create to match the test name (or rename the test if run is intentional).

        auto result = RunWslc(std::format(
            L"container run --name {} --mount \"type=bind,source={},target=/data\" {} true",
            WslcContainerName,
            source.wstring(),
            AlpineImage.NameAndTag()));

src/windows/wslcsession/WSLCContainer.cpp:668

• ConvertAndValidateMounts() validates NamedVolumes[i].Name but not NamedVolumes[i].ContainerPath before passing it to addDestination(). A null ContainerPath would currently result in a generic E_INVALIDARG without actionable context. Add an explicit null check (similar to ProcessNamedVolumes).

        THROW_HR_IF_NULL_MSG(E_INVALIDARG, containerOptions.NamedVolumes[i].Name, "NamedVolume at index %lu has null Name", i);
        addDestination(containerOptions.NamedVolumes[i].ContainerPath);
    }

src/windows/wslcsession/WSLCContainer.cpp:674

• ConvertAndValidateMounts() passes Tmpfs[i].Destination to addDestination() without validating it for null. Add a null check with the index so malformed input yields a clear diagnostic rather than a generic failure.

    for (ULONG i = 0; i < containerOptions.TmpfsCount; ++i)
    {
        addDestination(containerOptions.Tmpfs[i].Destination);
    }

src/windows/wslcsession/WSLCContainer.cpp:661

• ConvertAndValidateMounts() checks Volumes[i].HostPath for null but passes Volumes[i].ContainerPath to addDestination() without validating it. If ContainerPath is null at this COM boundary, this will throw with an unhelpful generic error (or worse, depending on macro behavior). Add an explicit null check with the index for diagnostics.

This issue also appears in the following locations of the same file:

• line 666
• line 671

        THROW_HR_IF_NULL_MSG(E_INVALIDARG, containerOptions.Volumes[i].HostPath, "Volumes[%lu].HostPath is null", i);
        addDestination(containerOptions.Volumes[i].ContainerPath);

test/windows/wslc/e2e/WSLCE2EContainerCreateTests.cpp:800

• This test is named as a Container_Create scenario, but it invokes container run, which exercises a different code path (and can fail at start time rather than create time). To specifically validate container create behavior for missing bind sources, the command should use container create (and not run).

        auto result = RunWslc(std::format(
            L"container run --name {} --mount \"type=bind,source={},target=/data\" {} true",
            WslcContainerName,
            source.wstring(),
            AlpineImage.NameAndTag()));

src/windows/wslc/services/ContainerService.cpp:33

• The namespace alias mount is introduced here but never used, which adds noise and may trigger unused-alias warnings depending on toolchain settings. It can be removed.

namespace wsl::windows::wslc::services {
namespace mount = wsl::windows::common::mount;

test/windows/wslc/WSLCCLIMountParserUnitTests.cpp:222

• This mount spec (type=volume,...,bind-recursive=enabled) is listed as a valid case here, but the same exact input is also listed as an invalid (bind-* family mismatch) case later in c_invalidMountCases (lines ~350-351). With the current parser, bind-recursive is a bind-only option, so this entry will make the valid-case loop fail.

        {L"type=volume,source=data-volume,target=/data,bind-recursive=enabled",
         mount::Type::Volume,
         L"data-volume",
         "/data",
         false,
         {},
         {},
         ""},

test/windows/wslc/e2e/WSLCE2EContainerCreateTests.cpp:802

• This test is in WSLCE2EContainerCreateTests.cpp and is named Container_Create_*, but it invokes container run. Because run has additional behavior (and can exercise different code paths than create), this doesn’t reliably validate container create rejecting missing bind sources.

        auto result = RunWslc(std::format(
            L"container run --name {} --mount \"type=bind,source={},target=/data\" {} true",
            WslcContainerName,
            source.wstring(),
            AlpineImage.NameAndTag()));
        result.Verify({.Stdout = L"", .Stderr = FormatWslcError(Localization::MessageWslcBindSourcePathNotFound(source.wstring())), .ExitCode = 1});

test/windows/wslc/e2e/WSLCE2EContainerCreateTests.cpp:820

• This Container_Create_* test also runs container run instead of container create, so it’s not specifically exercising the create path’s behavior around creating missing bind-source directories. Either switch to container create (and clean up the created container), or rename/move the test so it’s clear it’s validating run.

        auto result = RunWslc(std::format(
            L"container run --name {} --volume \"{}:/data\" {} true", WslcContainerName, source.wstring(), AlpineImage.NameAndTag()));
        result.Verify({.Stdout = L"", .Stderr = L"", .ExitCode = 0});
        VERIFY_IS_TRUE(std::filesystem::is_directory(source));
        EnsureContainerDoesNotExist(WslcContainerName);

src/windows/common/MountSpecParsing.cpp:585

• PR description says anonymous volumes are rejected, but ValidateMountSpec currently allows type=volume with an empty source (i.e., anonymous volume) as long as the name is either empty or a valid named volume. Either update the PR description to match the implemented behavior, or enforce source for type=volume if anonymous volumes truly aren’t supported.

    case Type::Volume:
        if (!mount.Source.empty() && !IsValidNamedVolumeName(mount.Source))
        {
            ThrowValidation(Localization::WSLCCLI_MountVolumeSourceInvalidError());
        }