Show just the current branch in Git

With Git 2.22 (Q2 2019), you will have a simpler approach: git branch --show-current.

See commit 0ecb1fc (25 Oct 2018) by Daniels Umanovskis (umanovskis).
^{(Merged by Junio C Hamano -- gitster -- in commit 3710f60, 07 Mar 2019)}

branch: introduce --show-current display option

When called with --show-current, git branch will print the current branch name and terminate.
Only the actual name gets printed, without refs/heads.
In detached HEAD state, nothing is output.

Intended both for scripting and interactive/informative use.
Unlike git branch --list, no filtering is needed to just get the branch name.

See the original discussion on the Git mailing list in Oct. 2018, and the actual patch.

Warning: as mentioned in the comments by Olivier:

This does not work in every situation!
When you are for instance in a submodule, it does not work.
'git symbolic-ref --short HEAD' always works.

This is not shorter, but it deals with detached branches as well:

git branch | awk -v FS=' ' '/\*/{print $NF}' | sed 's|[()]||g'

For those liking aliases: Put the following to your .zshrc so you get easier git command flow:

alias gpsu="git push --set-upstream origin $(git symbolic-ref --short HEAD)"

Someone might find this (git show-branch --current) helpful. The current branch is shown with a * mark.

host-78-65-229-191:idp-mobileid user-1$ git show-branch --current
! [CICD-1283-pipeline-in-shared-libraries] feat(CICD-1283): Use latest version of custom release plugin.
 * [master] Merge pull request #12 in CORES/idp-mobileid from feature/fix-schema-name to master
--
+  [CICD-1283-pipeline-in-shared-libraries] feat(CICD-1283): Use latest version of custom release plugin.
+  [CICD-1283-pipeline-in-shared-libraries^] feat(CICD-1283): Used the renamed AWS pipeline.
+  [CICD-1283-pipeline-in-shared-libraries~2] feat(CICD-1283): Point to feature branches of shared libraries.
-- [master] Merge pull request #12 in CORES/idp-mobileid from feature/fix-schema-name to master

For completeness, echo $(__git_ps1), on Linux at least, should give you the name of the current branch surrounded by parentheses.

This may be useful is some scenarios as it is not a Git command (while depending on Git), notably for setting up your Bash command prompt to display the current branch.

For example:

/mnt/c/git/ConsoleApp1 (test-branch)> echo $(__git_ps1)
(test-branch)
/mnt/c/git/ConsoleApp1 (test-branch)> git checkout master
Switched to branch 'master'
/mnt/c/git/ConsoleApp1 (master)> echo $(__git_ps1)
(master)
/mnt/c/git/ConsoleApp1 (master)> cd ..
/mnt/c/git> echo $(__git_ps1)

/mnt/c/git>