Freeciv

I'd want cleaner solution. By making team mate's real embassy look like embassy effect already lead you to trouble forcing you to make more hacky code to research_total_bulbs_required().

I'll try to make alternative patch myself.

Untested patch for master that adds team_has_embassy() function, and calls it instead of player_has_embassy() where ever the question is about getting intelligence information. There's several cases where it is not called instead of player_has_embassy(). Most notable such functional difference to your patch is that meeting between players is not enabled by an embassy of an teammate.
One thing to review is if client side has enough information for its calls to team_has_embassy() to work sensibly.

Marko Lindqvist wrote:

One thing to review is if client side has enough information for its calls to team_has_embassy() to work sensibly.

Yes, client knows if there's an embassy between other players, if client has embassy - or equivalent info - with the player who owns embassy to third player.

Not targeting to S2_6 as too risky change for mature branch, and someone might even consider this a rule change.

When a team member establish an embassy, it doesn't immediately become possible for the other team member (gui) to access the information - presumably we're lacking player information refresh.

- Added sending necessary player info updates to clients