fix(mxc): preserve JSON arguments in PowerShell 5.1 (NVBug 6843165)

crates/openshell-driver-mxc/examples/run-openclaw-forward-test.ps1

@@ -137,6 +137,60 @@ function Copy-ItemRetry([string]$src, [string]$dst, [int]$attempts = 10, [int]$d
 function Ok([string]$m)   { Write-Host "[OK]   $m" -ForegroundColor Green }
 function Bad([string]$m)  { Write-Host "[FAIL] $m" -ForegroundColor Red }
 
+# Build one CreateProcess-compatible command-line argument. Windows PowerShell
+# 5.1 removes embedded quotes and can split JSON values at embedded spaces when
+# invoking native commands through the call operator.
+function Quote-NativeArgument([string]$value) {
+  if ($value.Length -gt 0 -and $value -notmatch '[\s"]') { return $value }
+
+  $quoted = New-Object System.Text.StringBuilder
+  [void]$quoted.Append('"')
+  $backslashes = 0
+  foreach ($ch in $value.ToCharArray()) {
+    if ($ch -eq '\') {
+      $backslashes++
+      continue
+    }
+    if ($ch -eq '"') {
+      [void]$quoted.Append(('\' * (2 * $backslashes + 1)))
+      [void]$quoted.Append('"')
+    } else {
+      if ($backslashes -gt 0) { [void]$quoted.Append(('\' * $backslashes)) }
+      [void]$quoted.Append($ch)
+    }
+    $backslashes = 0
+  }
+  if ($backslashes -gt 0) { [void]$quoted.Append(('\' * (2 * $backslashes))) }
+  [void]$quoted.Append('"')
+  return $quoted.ToString()
+}
+
+function Invoke-NativeCaptured([string]$filePath, [string[]]$argumentList) {
+  $startInfo = New-Object System.Diagnostics.ProcessStartInfo
+  $startInfo.FileName = $filePath
+  $startInfo.Arguments = (($argumentList | ForEach-Object { Quote-NativeArgument $_ }) -join ' ')
+  $startInfo.UseShellExecute = $false
+  $startInfo.CreateNoWindow = $true
+  $startInfo.RedirectStandardOutput = $true
+  $startInfo.RedirectStandardError = $true
+
+  $process = New-Object System.Diagnostics.Process
+  $process.StartInfo = $startInfo
+  if (-not $process.Start()) { throw "failed to start $filePath" }
+  $stdout = $process.StandardOutput.ReadToEndAsync()
+  $stderr = $process.StandardError.ReadToEndAsync()
+  $process.WaitForExit()
+  $output = @($stdout.Result, $stderr.Result) |
+    Where-Object { -not [string]::IsNullOrWhiteSpace($_) } |
+    ForEach-Object { $_ -split "`r?`n" } |
+    Where-Object { -not [string]::IsNullOrWhiteSpace($_) }
+
+  return @{
+    ExitCode = $process.ExitCode
+    Output = @($output)
+  }
+}
+
 function Grant-AppContainerWritableDirectory([string]$Path) {
   # AppContainer access is a dual check: the generated package SID grant from
   # MXC is necessary, but OpenClaw's SQLite staging also needs the two built-in
@@ -453,14 +507,14 @@ try {
     "--env", "NEMOCLAW_MXC_EGRESS_LOOPBACK_PORT=29999",
     "--no-tty", "--", "exit"
   )
-  # Windows PowerShell 5.1 wraps native stderr as ErrorRecord objects. Keep
-  # warnings in the captured diagnostic without letting them terminate the
-  # command before its real exit code and output are collected.
-  $createPrevEAP = $ErrorActionPreference
-  $ErrorActionPreference = "Continue"
-  try { $createOut = & $cli @createArgs 2>&1; $createCode = $LASTEXITCODE }
-  catch { $createOut = $_.Exception.Message; $createCode = 1 }
-  finally { $ErrorActionPreference = $createPrevEAP }
+  try {
+    $createResult = Invoke-NativeCaptured $cli $createArgs
+    $createOut = $createResult.Output
+    $createCode = $createResult.ExitCode
+  } catch {
+    $createOut = $_.Exception.Message
+    $createCode = 1
+  }
   $createBenign = Show-SandboxCreate $createOut $SandboxName
   if ($createCode -ne 0 -and -not $createBenign) {
     throw "sandbox create '$SandboxName' failed (exit $createCode): $($createOut | Out-String)"

crates/openshell-driver-mxc/examples/run-ws-agent-test.ps1

@@ -112,6 +112,60 @@ function Esc([string]$p) { return $p.Replace('\', '\\') }
 # Convert Windows path to forward-slash form (TOML values).
 function Fwd([string]$p) { return $p.Replace('\', '/') }
 
+# Build one CreateProcess-compatible command-line argument. Windows PowerShell
+# 5.1 removes embedded quotes and can split JSON values at embedded spaces when
+# invoking native commands through the call operator.
+function Quote-NativeArgument([string]$value) {
+    if ($value.Length -gt 0 -and $value -notmatch '[\s"]') { return $value }
+
+    $quoted = New-Object System.Text.StringBuilder
+    [void]$quoted.Append('"')
+    $backslashes = 0
+    foreach ($ch in $value.ToCharArray()) {
+        if ($ch -eq '\') {
+            $backslashes++
+            continue
+        }
+        if ($ch -eq '"') {
+            [void]$quoted.Append(('\' * (2 * $backslashes + 1)))
+            [void]$quoted.Append('"')
+        } else {
+            if ($backslashes -gt 0) { [void]$quoted.Append(('\' * $backslashes)) }
+            [void]$quoted.Append($ch)
+        }
+        $backslashes = 0
+    }
+    if ($backslashes -gt 0) { [void]$quoted.Append(('\' * (2 * $backslashes))) }
+    [void]$quoted.Append('"')
+    return $quoted.ToString()
+}
+
+function Invoke-NativeCaptured([string]$filePath, [string[]]$argumentList) {
+    $startInfo = New-Object System.Diagnostics.ProcessStartInfo
+    $startInfo.FileName = $filePath
+    $startInfo.Arguments = (($argumentList | ForEach-Object { Quote-NativeArgument $_ }) -join ' ')
+    $startInfo.UseShellExecute = $false
+    $startInfo.CreateNoWindow = $true
+    $startInfo.RedirectStandardOutput = $true
+    $startInfo.RedirectStandardError = $true
+
+    $process = New-Object System.Diagnostics.Process
+    $process.StartInfo = $startInfo
+    if (-not $process.Start()) { throw "failed to start $filePath" }
+    $stdout = $process.StandardOutput.ReadToEndAsync()
+    $stderr = $process.StandardError.ReadToEndAsync()
+    $process.WaitForExit()
+    $output = @($stdout.Result, $stderr.Result) |
+        Where-Object { -not [string]::IsNullOrWhiteSpace($_) } |
+        ForEach-Object { $_ -split "`r?`n" } |
+        Where-Object { -not [string]::IsNullOrWhiteSpace($_) }
+
+    return @{
+        ExitCode = $process.ExitCode
+        Output = @($output)
+    }
+}
+
 # -WsPort is NOT actually wired through end to end: the in-sandbox server's
 # port is a compile-time const (WS_PORT = 22000 in mxc-ws-agent.rs) -- the
 # TOML generation below doesn't patch it. Rather than silently accept an
@@ -485,14 +539,15 @@ try {
         # Use the same pattern as run-mxc-e2e.ps1: pass --no-tty with a no-op
         # command so the CLI fires the SSH attempt, fails quickly (connection
         # refused), and returns.  Do NOT gate on exit code here.
-        $createOut = & $cli sandbox create `
-            --name $sandboxName `
-            --policy $policyUsed `
-            --driver-config-json $driverConfigJson `
-            --no-tty `
-            -- cmd.exe /c exit 0 `
-            2>&1
-        $createExitCode = $LASTEXITCODE
+        $createResult = Invoke-NativeCaptured $cli @(
+            "sandbox", "create",
+            "--name", $sandboxName,
+            "--policy", $policyUsed,
+            "--driver-config-json", $driverConfigJson,
+            "--no-tty", "--", "cmd.exe", "/c", "exit", "0"
+        )
+        $createOut = $createResult.Output
+        $createExitCode = $createResult.ExitCode
     } catch {
         $createOut = $_.Exception.Message; $createExitCode = 1
     }

crates/openshell-driver-mxc/tests/powershell_native_arguments.rs

@@ -0,0 +1,95 @@
+// SPDX-FileCopyrightText: Copyright (c) 2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+#[cfg(windows)]
+#[test]
+fn shipped_runners_preserve_driver_config_json_in_windows_powershell() {
+    let root = std::path::Path::new(env!("CARGO_MANIFEST_DIR"));
+    let directory = tempfile::tempdir().expect("create native-argument test directory");
+    let receiver = directory.path().join("capture native arguments.ps1");
+    std::fs::write(
+        &receiver,
+        r#"
+param(
+    [Parameter(Mandatory = $true, Position = 0)] [string] $Before,
+    [Parameter(Mandatory = $true, Position = 1)] [string] $DriverConfigJson,
+    [Parameter(Mandatory = $true, Position = 2)] [string] $After
+)
+
+[Console]::OutputEncoding = [System.Text.Encoding]::UTF8
+Write-Output "BEFORE=$Before"
+Write-Output "JSON=$DriverConfigJson"
+Write-Output "AFTER=$After"
+"#,
+    )
+    .expect("write native-argument receiver");
+
+    let verifier = r#"
+$ErrorActionPreference = "Stop"
+$tokens = $null
+$errors = $null
+$ast = [System.Management.Automation.Language.Parser]::ParseFile(
+    $env:OPENSHELL_RUNNER_PATH,
+    [ref] $tokens,
+    [ref] $errors
+)
+if ($errors.Count -gt 0) {
+    throw "runner has PowerShell syntax errors: $($errors.Message -join '; ')"
+}
+
+foreach ($name in @("Quote-NativeArgument", "Invoke-NativeCaptured")) {
+    $functionAst = $ast.Find({
+        param($node)
+        $node -is [System.Management.Automation.Language.FunctionDefinitionAst] -and
+            $node.Name -eq $name
+    }, $true)
+    if ($null -eq $functionAst) { throw "$name is missing" }
+    Invoke-Expression $functionAst.Extent.Text
+}
+
+$expected = @{
+    mxc = @{
+        command = @("C:/Program Files/OpenShell/agent.exe", "server mode")
+        cwd = "C:/work/path with spaces"
+    }
+} | ConvertTo-Json -Compress -Depth 4
+$powershell = Join-Path $env:SystemRoot "System32/WindowsPowerShell/v1.0/powershell.exe"
+$result = Invoke-NativeCaptured $powershell @(
+    "-NoLogo", "-NoProfile", "-NonInteractive", "-File",
+    $env:OPENSHELL_ARGUMENT_RECEIVER,
+    "before value", $expected, "after value"
+)
+if ($result.ExitCode -ne 0) {
+    throw "argument receiver exited $($result.ExitCode): $($result.Output -join [Environment]::NewLine)"
+}
+
+$lines = @(($result.Output -join "`n") -split "`r?`n")
+$before = $lines | Where-Object { $_ -like "BEFORE=*" } | Select-Object -First 1
+$json = $lines | Where-Object { $_ -like "JSON=*" } | Select-Object -First 1
+$after = $lines | Where-Object { $_ -like "AFTER=*" } | Select-Object -First 1
+if ($before -ne "BEFORE=before value") { throw "leading argument changed: $before" }
+if ($null -eq $json -or $json.Substring(5) -cne $expected) {
+    throw "driver config JSON changed: expected '$expected', captured '$json'"
+}
+if ($after -ne "AFTER=after value") { throw "trailing argument changed: $after" }
+"#;
+
+    for runner in ["run-ws-agent-test.ps1", "run-openclaw-forward-test.ps1"] {
+        let runner_path = root.join("examples").join(runner);
+        let output = std::process::Command::new("powershell.exe")
+            .args(["-NoLogo", "-NoProfile", "-NonInteractive", "-Command"])
+            .arg(verifier)
+            .env("OPENSHELL_RUNNER_PATH", &runner_path)
+            .env("OPENSHELL_ARGUMENT_RECEIVER", &receiver)
+            .output()
+            .unwrap_or_else(|error| {
+                panic!("failed to launch Windows PowerShell for {runner}: {error}")
+            });
+        assert!(
+            output.status.success(),
+            "{runner} corrupted a native argument:\nstdout:\n{}\nstderr:\n{}",
+            String::from_utf8_lossy(&output.stdout),
+            String::from_utf8_lossy(&output.stderr),
+        );
+    }
+}