Show effective/actual author and committer used by Git

Question

Is there a Git command to display author and committer which would be used in the next commit based on all configuration sources applied?

One of the reason for this question is that I cannot find username (committer reported in example below) in any of the files:

grep -r obsdev .git/config ~/.gitconfig /etc/gitconfig
# no output

Apparently, there is another configuration source.

The point is that I don't want to learn about any possible configuration source existing now, or in the future, or order in which they apply and override each other. Instead, I want to let Git figure out and display final/effective author/committer values.

Example

Under some conditions (like command line option --author) Git displays commented out Author: and Committer: fields in editor for commit message:

# Please enter the commit message for your changes. Lines starting              
# with '#' will be ignored, and an empty message aborts the commit.             
#                                                                               
# Author:    First Last <[email protected]>                               
# Committer: username <[email protected]>                              
#   
...

Is there a way to show these fields without trying to make a commit?

Alternatively, is it possible to force Git provide comments containing Author: and Committer: fields in the commit message editor under any circumstances without any command line options even when defaults are used (without overriding defaults)?

Answer 1

You can use git var:

# show the author (sed is there to strip the timestamp)
git var GIT_AUTHOR_IDENT | sed -r 's/( [^ ]+){2}$//'
# and the committer
git var GIT_COMMITTER_IDENT | sed -r 's/( [^ ]+){2}$//'

But if you haven't configured your name and email, it will print a warning instead of giving a value. A workaround would be:

# show the author
git var -l | grep -E '^GIT_AUTHOR_IDENT=' | sed -r 's/^[^=]+=//;s/( [^ ]+){2}$//'
# and the committer
git var -l | grep -E '^GIT_COMMITTER_IDENT=' | sed -r 's/^[^=]+=//;s/( [^ ]+){2}$//'