fix: Revert doublestar v4 update [backport]

[grafana-alloybot]

Backport of #5434

This PR backports #5434 to release/v1.13.

Original PR Author

@kalleep

Description

Reverts #5148

Discovered that updating to v4 introduces regression on windows around case sensitivity for paths. So we need to revert and look into that before updating.

---

This backport was created automatically.

[github-actions]

🔍 Dependency Review

github.com/bmatcuk/doublestar/v4 v4.9.1 -> github.com/bmatcuk/doublestar v1.3.4 — ⚠️ Needs Review

This is a major version change (v4 -> v1) with API differences. Your PR already adjusts imports and replaces FilepathGlob with Glob, but there are a couple of behavioral differences to double‑check, especially around path separator handling on Windows.

What to change/verify (to maintain existing behavior):

• Replace v4’s filepath-based globbing call with v1’s:

  • v4: doublestar.FilepathGlob(pattern)
  • v1: doublestar.Glob(pattern)

• Ensure exclude patterns normalize path separators when using PathMatch:

  • v1’s PathMatch follows filepath rules (OS-specific separators). If user/app config provides forward slashes (e.g., in YAML), normalize with filepath.FromSlash before calling PathMatch to preserve cross-platform behavior equivalent to prior code.

Recommended code changes (keep separator normalization):

internal/component/local/file_match/watch.go

-   matches, err := doublestar.Glob(w.getPath())
+   matches, err := doublestar.Glob(w.getPath())
    if err != nil {
        return nil, err
    }
    exclude := w.getExcludePath()
    for _, m := range matches {
        if exclude != "" {
-           if match, _ := doublestar.PathMatch(exclude, m); match {
+           if match, _ := doublestar.PathMatch(filepath.FromSlash(exclude), m); match {
                continue
            }
        }

internal/component/loki/source/file/resolver.go

-       matches, err := doublestar.Glob(targetPath)
+       matches, err := doublestar.Glob(targetPath)
        if err != nil {
            level.Error(s.logger).Log("msg", "failed to resolve target", "error", err)
            continue
        }
        exclude, _ := target.Get(labelExclude)
        for _, m := range matches {
            if exclude != "" {
-               if match, _ := doublestar.PathMatch(exclude, m); match {
+               if match, _ := doublestar.PathMatch(filepath.FromSlash(exclude), m); match {
                    continue
                }
            }

Why this matters:

• In v4 you previously normalized with filepath.FromSlash(exclude) before PathMatch. Removing that for v1 can change behavior on Windows if patterns contain forward slashes. Keeping the normalization preserves the earlier, cross‑platform behavior.

No other v4‑specific APIs (like option-based calls) are present in this repository, so no further refactoring is required.

References (from upstream docs/changelog):

• v1 README/API: Glob(pattern string) uses filepath (OS-specific) rules and supports **; PathMatch uses filepath semantics.
• v4 README/API: Split APIs to distinguish path vs filepath semantics; FilepathGlob is the filepath (OS-specific) variant, while Glob is the path (/) variant. Moving to v1 requires using Glob for filepath semantics.

collector: github.com/bmatcuk/doublestar - -> v1.3.4 (indirect) — ✅ Safe

• Newly added as an indirect dependency; no repository code in this module directly references it.
• No code changes required here.

extension/alloyengine: github.com/bmatcuk/doublestar - -> v1.3.4 (indirect) — ✅ Safe

• Newly added as an indirect dependency; no repository code in this module directly references it.
• No code changes required here.

Notes

• The root module now directly depends on github.com/bmatcuk/doublestar v1.3.4 and retains github.com/bmatcuk/doublestar/v4 v4.9.1 as an indirect dependency (pulled by other packages). This is fine; both modules coexist under distinct import paths.
• Consider a quick grep for any remaining PathMatch uses to ensure separator normalization for user-supplied patterns if they can contain / on Windows.