nilctxpassed: ignore variadic spread slice arguments to prevent false positives

[Copilot]

nilctxpassed incorrectly flagged f(nil...) for variadic ...context.Context params by treating a spread slice argument as an individual context.Context element. This produced a factually wrong diagnostic for valid nil-slice variadic calls.

• Analyzer logic: variadic spread handling

  • In pkg/linters/nilctxpassed/nilctxpassed.go, the variadic branch now skips element-wise nil checks when the call uses ... on the final variadic argument (call.Ellipsis.IsValid() at the variadic slice position).
  • This preserves existing behavior for non-spread variadic calls (e.g., f(nil) is still reportable).

• Regression coverage: spread vs non-spread

  • In pkg/linters/nilctxpassed/testdata/src/nilctxpassed/nilctxpassed.go, added fixtures for:
    • takesVariadicCtx(nil...) → not flagged
    • takesVariadicCtx(existingSlice...) → not flagged
  • Existing takesVariadicCtx(nil) fixture remains flagged.

if sig.Variadic() && params.Len() > 0 && i >= params.Len()-1 {
    if call.Ellipsis.IsValid() && i == len(call.Args)-1 {
        // Spread passes the variadic slice, not an element.
        continue
    }
    sliceType, ok := params.At(params.Len() - 1).Type().(*types.Slice)
    if !ok {
        continue
    }
    paramType = sliceType.Elem()
}

[pelikhan]

@copilot merge main and recompile

[Copilot]

@copilot merge main and recompile

Done in 0de7c39 — merged main into this branch and ran make recompile.

[Copilot]

Pull request overview

Fixes a nilctxpassed false positive for nil variadic slice spreads.

Changes:

• Skips element-level checks for spread variadic arguments.
• Adds regression fixtures for nil and existing slice spreads.

Show a summary per file

File	Description
pkg/linters/nilctxpassed/nilctxpassed.go	Corrects variadic spread analysis.
pkg/linters/nilctxpassed/testdata/src/nilctxpassed/nilctxpassed.go	Adds spread-call regression coverage.

Review details

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• Files reviewed: 2/2 changed files
• Comments generated: 0
• Review effort level: Medium

[github-actions]

🎉 This pull request is included in a new release.

Release: v0.82.10