[refactor] pkg/testutil: split tempdir.go - CaptureStderr and StripYAMLCommentHeader dont belong #60544

Executive Summary

Semantic clustering analysis of the precomputed package slice for this run: pkg/testutil and pkg/timeutil (2 non-test .go files, 8 functions total). Each package contains exactly one non-test source file, so the analysis is narrow by design.

• pkg/timeutil/format.go — clean, single-purpose, no findings.
• pkg/testutil/tempdir.go — 2 of 4 functions are outliers relative to the file's name/purpose (temp-directory management), violating the one-file-per-feature convention.
• No duplicate or near-duplicate implementations found within the analyzed scope.

Identified Issues

1. Outlier functions in pkg/testutil/tempdir.go

The file is named and documented around temp-directory lifecycle (GetTestRunDir, TempDir), but also contains two functions with unrelated responsibilities:

• CaptureStderr(t *testing.T, fn func()) string (tempdir.go:76-100) — stderr piping/capture utility, unrelated to temp directories. Widely used (20+ call sites across pkg/workflow, pkg/cli, pkg/parser, pkg/actionpins).
• StripYAMLCommentHeader(yamlContent string) string (tempdir.go:105-115) — YAML text-processing helper, unrelated to temp directories. Used in pkg/testutil/tempdir_test.go, pkg/testutil/spec_test.go, and 2 files in pkg/workflow.

Recommendation: Split tempdir.go by feature, per the one-file-per-feature convention:

• Keep GetTestRunDir and TempDir in tempdir.go.
• Move CaptureStderr to a new pkg/testutil/capture.go.
• Move StripYAMLCommentHeader to a new pkg/testutil/yaml.go (or fold into an existing YAML-focused test helper file if one exists outside this scope).

No implementation changes needed — this is a same-package file move, so all existing testutil.XxxYyy call sites remain valid.

Estimated impact: Low effort (pure file split within one package), improves discoverability and keeps each file's contents matching its name.

2. pkg/timeutil/format.go — no issues found

All four functions (round1, FormatDuration, FormatDurationMs, FormatDurationNs) are duration-formatting concerns consistent with the file name. round1 is a small private helper (<5 lines) used only within this file — acceptable per the "trivial helper" exclusion.

3. Duplicate detection

No duplicate or near-duplicate functions were found. A repo-wide search for sibling capture/strip helpers (e.g. CaptureStdout, StripComment*) found none, so CaptureStderr and StripYAMLCommentHeader are not consolidation candidates — only relocation candidates.

Refactoring Recommendations

Priority 1 (low effort, do when touching this package)

1. Move CaptureStderr → pkg/testutil/capture.go.
2. Move StripYAMLCommentHeader → pkg/testutil/yaml.go.

No Priority 2/3 items identified in this scope.

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Generated by 🔧 Semantic Function Refactoring · claude · sonnet50 · 145.1 AIC · ⌖ 40.7 AIC · ⊞ 10.8K · ◷

• expires on Sep 14, 2026, 6:41 PM UTC-08:00