Merge branch 'dl/octopus-graph-bug'

"git log --graph" for an octopus merge is sometimes colored
incorrectly, which is demonstrated and documented but not yet
fixed.

* dl/octopus-graph-bug:
  t4214: demonstrate octopus graph coloring failure
  t4214: explicitly list tags in log
  t4214: generate expect in their own test cases
  t4214: use test_merge
  test-lib: let test_merge() perform octopus merges

t/test-lib-functions.sh

@@ -228,9 +228,11 @@ test_commit () {
 # can be a tag pointing to the commit-to-merge.
 
 test_merge () {
+	label="$1" &&
+	shift &&
 	test_tick &&
-	git merge -m "$1" "$2" &&
-	git tag "$1"
+	git merge -m "$label" "$@" &&
+	git tag "$label"
 }
 
 # Efficiently create <nr> commits, each with a unique number (from 1 to <nr>