[Repo Assist] perf: eliminate LINQ Skip allocations in ExecShellWrapperParser#193
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shanselman merged 1 commit intomasterfrom Apr 23, 2026
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Replace string.Join(", ", tokens.Skip(i + 1)) with the indexed
string.Join(string, string[], int, int) overload in the three shell-
payload reconstruction sites (cmd /c, bash -c, powershell -Command).
Changes:
- Tokenize() now returns string[] instead of List<string>; callers
already received it as an opaque list so the type narrowing is safe.
- ParsePowerShellPayload signature updated to string[] to match.
- Three string.Join(" ", tokens.Skip(i + 1)) calls replaced with
string.Join(" ", tokens, i + 1, tokens.Length - i - 1) — uses the
well-known BCL overload that slices directly into the array with no
iterator allocation.
- Removes the now-unused 'using System.Linq;' import.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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🤖 This is an automated PR from Repo Assist.
Summary
Eliminates LINQ
Skipiterator allocations in the shell-payload reconstruction path ofExecShellWrapperParser.What changed
Three calls of the form:
are replaced with the indexed BCL overload:
The three sites are:
cmd /candcmd /kpayload reconstructionbash -c/sh -cpayload reconstructionpowershell -Command/pwsh -Commandpayload reconstructionSupporting changes:
Tokenize()return type changed fromList<string>tostring[](returnstokens.ToArray()) so the indexedstring.Joinoverload is available.ParsePowerShellPayloadparameter type updated fromIReadOnlyList<string>tostring[]to match.using System.Linq;removed (now unused).Why
Each
tokens.Skip(i + 1)call allocates a LINQWhereEnumerableIterator/SkipEnumerablewrapper.string.Join(string, string[], int, int)takes the array and index/count directly — no iterator object is created.This fires on every shell-wrapped command that arrives over the node connection (
cmd /c ...,bash -c ...,powershell -Command ...).Test Status
dotnet build— succeeded, 0 errors, 0 warningsdotnet test OpenClaw.Shared.Tests— passed (exit 0)dotnet test OpenClaw.Tray.Tests— passed (exit 0)