jojo/services/convert
Mathieu Fenniak f93d2cb261 ci: detect and prevent empty case statements in Go code (#11593)
One of the security patches released 2026-03-09 [fixed a vulnerability](https://codeberg.org/forgejo/forgejo/pulls/11513/commits/d1c7b04d09f6a13896eaa1322ac690b2021539da) caused by a misapplication of Go `case` statements, where the implementation would have been correct if Go `case` statements automatically fall through to the next case block, but they do not.  This PR adds a semgrep rule which detects any empty `case` statement and raises an error, in order to prevent this coding mistake in the future.

For example, code like this will now trigger a build error:
```go
	switch setting.Protocol {
	case setting.HTTPUnix:
	case setting.FCGI:
	case setting.FCGIUnix:
	default:
		defaultLocalURL := string(setting.Protocol) + "://"
	}
```

Example error:
```
    cmd/web.go
   ❯❯❱ semgrep.config.forgejo-switch-empty-case
          switch has a case block with no content. This is treated as "break" by Go, but developers may
          confuse it for "fallthrough".  To fix this error, disambiguate by using "break" or
          "fallthrough".

          279┆ switch setting.Protocol {
          280┆ case setting.HTTPUnix:
          281┆ case setting.FCGI:
          282┆ case setting.FCGIUnix:
          283┆ default:
          284┆   defaultLocalURL := string(setting.Protocol) + "://"
          285┆   if setting.HTTPAddr == "0.0.0.0" {
          286┆           defaultLocalURL += "localhost"
          287┆   } else {
          288┆           defaultLocalURL += setting.HTTPAddr
```

As described in the error output, this error can be fixed by explicitly listing `break` (the real Go behaviour, to do nothing in the block), or by listing `fallthrough` (if the intent was to fall through).

All existing code triggering this detection has been changed to `break` (or, rarely, irrelevant cases have been removed), which should maintain the same code functionality.  While performing this fixup, a light analysis was performed on each case and they *appeared* correct, but with ~65 cases I haven't gone into extreme depth.

Tests are present for the semgrep rule in `.semgrep/tests/go.go`.

## Checklist

The [contributor guide](https://forgejo.org/docs/next/contributor/) contains information that will be helpful to first time contributors. There also are a few [conditions for merging Pull Requests in Forgejo repositories](https://codeberg.org/forgejo/governance/src/branch/main/PullRequestsAgreement.md). You are also welcome to join the [Forgejo development chatroom](https://matrix.to/#/#forgejo-development:matrix.org).

### Documentation

- [ ] I created a pull request [to the documentation](https://codeberg.org/forgejo/docs) to explain to Forgejo users how to use this change.
- [x] I did not document these changes and I do not expect someone else to do it.

### Release notes

- [ ] This change will be noticed by a Forgejo user or admin (feature, bug fix, performance, etc.). I suggest to include a release note for this change.
- [x] This change is not visible to a Forgejo user or admin (refactor, dependency upgrade, etc.). I think there is no need to add a release note for this change.

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/11593
Reviewed-by: Gusted <gusted@noreply.codeberg.org>
Co-authored-by: Mathieu Fenniak <mathieu@fenniak.net>
Co-committed-by: Mathieu Fenniak <mathieu@fenniak.net>
2026-03-10 02:50:28 +01:00
..
action.go bug: unify RepoActionRun and ActionRun structs (#8250) 2025-06-23 07:54:32 +02:00
activity.go chore: branding import path (#7337) 2025-03-27 19:40:14 +00:00
activitypub_person.go Add ActivityPub Person follow from distant (#8720) 2025-08-03 11:55:01 +02:00
activitypub_user_action.go ci: detect and prevent empty case statements in Go code (#11593) 2026-03-10 02:50:28 +01:00
attachment.go fix(ui): Add pasted images to dropzone 2025-06-30 12:42:22 +02:00
attachment_test.go fix(ui): Add pasted images to dropzone 2025-06-30 12:42:22 +02:00
convert.go feat: implement ephemeral runners (#9962) 2026-02-16 18:56:56 +01:00
convert_test.go chore: revise runner REST API endpoints (#10450) 2025-12-21 17:21:02 +01:00
git_commit.go chore: ensure consistent import aliasing for services and models (#10253) 2025-11-30 17:00:57 +01:00
git_commit_test.go Update module github.com/golangci/golangci-lint/cmd/golangci-lint to v2 (forgejo) (#7367) 2025-03-28 22:22:21 +00:00
issue.go chore: branding import path (#7337) 2025-03-27 19:40:14 +00:00
issue_comment.go chore: branding import path (#7337) 2025-03-27 19:40:14 +00:00
issue_test.go test: prevent XSS for label rendering 2025-06-27 13:27:06 +02:00
main_test.go chore: move all test blank imports in a single package (#10662) 2026-01-02 05:32:32 +01:00
mirror.go feat: add configuration to only push mirror selected branches (#7823) 2025-07-12 00:39:35 +02:00
notification.go feat: rework notification table (#9926) 2025-11-29 23:03:56 +01:00
package.go chore: branding import path (#7337) 2025-03-27 19:40:14 +00:00
pull.go feat: improve getting shortstat (#9587) 2025-10-10 14:15:38 +02:00
pull_review.go Update module github.com/golangci/golangci-lint/cmd/golangci-lint to v2 (forgejo) (#7367) 2025-03-28 22:22:21 +00:00
pull_test.go Update module github.com/golangci/golangci-lint/cmd/golangci-lint to v2 (forgejo) (#7367) 2025-03-28 22:22:21 +00:00
quota.go chore: ensure consistent import aliasing for services and models (#10253) 2025-11-30 17:00:57 +01:00
release.go feat: make upload URL compatible with GitHub API (#9285) 2025-09-15 15:53:35 +02:00
release_test.go feat: make upload URL compatible with GitHub API (#9285) 2025-09-15 15:53:35 +02:00
repository.go fix: hide user profile anonymous options on public repo APIs 2026-01-06 09:58:20 -07:00
status.go chore: branding import path (#7337) 2025-03-27 19:40:14 +00:00
user.go chore: branding import path (#7337) 2025-03-27 19:40:14 +00:00
user_test.go Update module github.com/golangci/golangci-lint/cmd/golangci-lint to v2 (forgejo) (#7367) 2025-03-28 22:22:21 +00:00
utils.go Add support for migrating from Pagure (#8513) 2025-08-11 16:56:26 +02:00
utils_test.go Update module github.com/golangci/golangci-lint/cmd/golangci-lint to v2 (forgejo) (#7367) 2025-03-28 22:22:21 +00:00
wiki.go chore: branding import path (#7337) 2025-03-27 19:40:14 +00:00