Merge branch 'ar/unconfuse-three-dots'

Ancient part of codebase still shows dots after an abbreviated
object name just to show that it is not a full object name, but
these ellipses are confusing to people who newly discovered Git
who are used to seeing abbreviated object names and find them
confusing with the range syntax.

* ar/unconfuse-three-dots:
  t2020: test variations that matter
  t4013: test new output from diff --abbrev --raw
  diff: diff_aligned_abbrev: remove ellipsis after abbreviated SHA-1 value
  t4013: prepare for upcoming "diff --raw --abbrev" output format change
  checkout: describe_detached_head: remove ellipsis after committish
  print_sha1_ellipsis: introduce helper
  Documentation: user-manual: limit usage of ellipsis
  Documentation: revisions: fix typo: "three dot" ---> "three-dot" (in line with "two-dot").

1 files changed, 8 insertions, 2 deletions

diff --git a/builtin/checkout.c b/builtin/checkout.c
index 9b886356bf..f9f3797e11 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -401,10 +401,16 @@ static void show_local_changes(struct object *head,
 static void describe_detached_head(const char *msg, struct commit *commit)
 {
 	struct strbuf sb = STRBUF_INIT;
+
 	if (!parse_commit(commit))
 		pp_commit_easy(CMIT_FMT_ONELINE, commit, &sb);
-	fprintf(stderr, "%s %s... %s\n", msg,
-		find_unique_abbrev(commit->object.oid.hash, DEFAULT_ABBREV), sb.buf);
+	if (print_sha1_ellipsis()) {
+		fprintf(stderr, "%s %s... %s\n", msg,
+			find_unique_abbrev(commit->object.oid.hash, DEFAULT_ABBREV), sb.buf);
+	} else {
+		fprintf(stderr, "%s %s %s\n", msg,
+			find_unique_abbrev(commit->object.oid.hash, DEFAULT_ABBREV), sb.buf);
+	}
 	strbuf_release(&sb);
 }