use proper subaddress

[TheFox0x7]

followup to #36550

[TheFox0x7]

FYI @Enzime

[silverwind]

This comment was written by an AI assistant (Claude Code).

Review of PR #36639 — "use proper subaddress"

This PR swaps the noreply email format from user+id@noreply to id+user@noreply, aligning with GitHub's format (ID+USERNAME@users.noreply.github.com). Overall, the change is correct and well-scoped.

Code correctness

The else branch addition in parseLocalPartToNameID is necessary and correct. After swapping the strings.Cut return values, when there is no + separator, the entire local-part ends up in idstr (previously it ended up in name). Without the else { name = idstr } fix, a plain username@noreply.host address would incorrectly return an empty name. Good catch.

Backward compatibility

The intermediate format introduced by #36550 (user+id@noreply) will no longer parse correctly — with the new code, user+id would attempt ParseInt("user") which fails, then return name="id" and id=0. Since #36550 hasn't shipped in a release yet, this is acceptable. Worth noting for anyone running main in production though.

The oldest format (username@noreply.host, no +) continues to work correctly.

Comparison with GitHub's implementation

Aspect	GitHub	Gitea (after this PR)
Format	ID+USERNAME@users.noreply.github.com	ID+username@<NoReplyAddress>
Legacy format	USERNAME@users.noreply.github.com (still recognized)	USERNAME@<NoReplyAddress> (still recognized)
Lookup priority	ID first, then username	ID first, then username (same)

One behavioral difference from GitHub worth being aware of: GitHub explicitly handles username renames — commits with the old USERNAME@users.noreply.github.com format continue to be attributed to the account even after a rename (since the old username stays reserved for a period). In Gitea, the plain-username lookup (GetUserByName) will resolve to whoever currently holds that username. This is pre-existing behavior not introduced by this PR, but it's one of the reasons GitHub moved to the ID+USERNAME format in the first place — the ID provides stable attribution across renames.

LGTM — the change is minimal, tests are updated to match, and the format now matches GitHub's convention.

[silverwind]

Might be worth implementing the user rename logic, e.g. keep original username in email after rename, if it's not too complex to implement.

[silverwind]

lgtm in any case

[silverwind]

Might be worth implementing the user rename logic, e.g. keep original username in email after rename, if it's not too complex to implement.

Actually I'm not sure the value of this. With ID present, there is no actual risk of impersonification attacks because a user ID can not be changed on any exposed API, to my knowledge.