Exit value with piped commands in bash

Whenever the output of a command is piped to another in bash, which command will the exit value (the $? variable) be returned from? The command that the output was piped from, or the command that the output was piped to?

Say, for example, in the command:

git diff | vim -

Would the $? variable come from the git diff command, or the vim - command?

Answer

The last command in the pipe.

$ false | echo -n
$ echo $?
0

$ true | echo -n
$ echo $?
0

$ true | echo -n | false
$ echo $?
1