Finding what branch a Git commit came from

Question

Is there a way to find out what branch a commit comes from given its SHA-1 hash value?

Bonus points if you can tell me how to accomplish this using Ruby Grit.

Answer 1

I think someone should face the same problem that can't find out the branch, although it actually exists in one branch.

You'd better pull all first:

git pull --all

Then do the branch search:

git name-rev <SHA>

or:

git branch --contains <SHA>

Answer 2

Aside from searching through all of the tree until you find a matching hash, no.

Answer 3

git branch --contains <ref> is the most obvious "porcelain" command to do this. If you want to do something similar with only "plumbing" commands:

COMMIT=$(git rev-parse <ref>) # expands hash if needed
for BRANCH in $(git for-each-ref --format "%(refname)" refs/heads); do
  if $(git rev-list $BRANCH | fgrep -q $COMMIT); then
    echo $BRANCH
  fi
done

(crosspost from this SO answer)

Answer 4

TL;DR:

Use the below if you care about shell exit statuses:

• branch-current - the current branch's name
• branch-names - clean branch names (one per line)
• branch-name - Ensure that only one branch is returned from branch-names

Both branch-name and branch-names accept a commit as the argument, and default to HEAD if none is given.

---

Aliases useful in scripting

branch-current = "symbolic-ref --short HEAD"  # https://stackoverflow.com/a/19585361/5353461
branch-names = !"[ -z \"$1\" ] && git branch-current 2>/dev/null || git branch --format='%(refname:short)' --contains \"${1:-HEAD}\" #"  # https://stackoverflow.com/a/19585361/5353461
branch-name = !"br=$(git branch-names \"$1\") && case \"$br\" in *$'\\n'*) printf \"Multiple branches:\\n%s\" \"$br\">&2; exit 1;; esac; echo \"$br\" #"

---

Commit only reachable from only one branch

% git branch-name eae13ea
master
% echo $?
0

• Output is to STDOUT
• Exit value is 0.

---

Commit reachable from multiple branches

% git branch-name 4bc6188
Multiple branches:
attempt-extract
master%
% echo $?
1

• Output is to STDERR
• The exit value is 1.

---

Because of the exit status, these can be safely built upon. For example, to get the remote used for fetching:

remote-fetch = !"branch=$(git branch-name \"$1\") && git config branch.\"$branch\".remote || echo origin #"

Answer 5

This simple command works like a charm:

git name-rev <SHA>

For example (where test-branch is the branch name):

git name-rev 651ad3a
251ad3a remotes/origin/test-branch

Even this is working for complex scenarios, like:

origin/branchA/
              /branchB
                      /commit<SHA1>
                                   /commit<SHA2>

Here git name-rev commit<SHA2> returns branchB.

Answer 6

To find the local branch:

grep -lR YOUR_COMMIT .git/refs/heads | sed 's/.git\/refs\/heads\///g'

To find the remote branch:

grep -lR $commit .git/refs/remotes | sed 's/.git\/refs\/remotes\///g'