diff --git a/tests/fetchGit.sh b/tests/fetchGit.sh
index 76390fa59..1e8963d76 100644
--- a/tests/fetchGit.sh
+++ b/tests/fetchGit.sh
@@ -41,6 +41,19 @@ export _NIX_FORCE_HTTP=1
 path=$(nix eval --impure --raw --expr "(builtins.fetchGit file://$repo).outPath")
 [[ $(cat $path/hello) = world ]]
 
+# Fetch a rev from another branch
+git -C $repo checkout -b devtest
+echo "different file" >> $TEST_ROOT/git/differentbranch
+git -C $repo add differentbranch
+git -C $repo commit -m 'Test2'
+git -C $repo checkout master
+devrev=$(git -C $repo rev-parse devtest)
+out=$(nix eval --impure --raw --expr "builtins.fetchGit { url = file://$repo; rev = \"$devrev\"; }" 2>&1) || status=$?
+[[ $status == 1 ]]
+[[ $out =~ 'Cannot find Git revision' ]]
+
+[[ $(nix eval --raw --expr "builtins.readFile (builtins.fetchGit { url = file://$repo; rev = \"$devrev\"; allRefs = true; } + \"/differentbranch\")") = 'different file' ]]
+
 # In pure eval mode, fetchGit without a revision should fail.
 [[ $(nix eval --impure --raw --expr "builtins.readFile (fetchGit file://$repo + \"/hello\")") = world ]]
 (! nix eval --raw --expr "builtins.readFile (fetchGit file://$repo + \"/hello\")")