for-each-ref: introduce %(upstream:track[short])

Introduce %(upstream:track) to display "[ahead M, behind N]" and
%(upstream:trackshort) to display "=", ">", "<", or "<>"
appropriately (inspired by contrib/completion/git-prompt.sh).

Now you can use the following format in for-each-ref:

  %(refname:short)%(upstream:trackshort)

to display refs with terse tracking information.

Note that :track and :trackshort only work with "upstream", and error
out when used with anything else.

Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/t/t6300-for-each-ref.sh b/t/t6300-for-each-ref.sh
index 1d998f8..d88d7ac 100755
--- a/t/t6300-for-each-ref.sh
+++ b/t/t6300-for-each-ref.sh
@@ -303,6 +303,33 @@ test_expect_success 'Check short upstream format' '
 	test_cmp expected actual
 '
 
+test_expect_success 'setup for upstream:track[short]' '
+	test_commit two
+'
+
+cat >expected <<EOF
+[ahead 1]
+EOF
+
+test_expect_success 'Check upstream:track format' '
+	git for-each-ref --format="%(upstream:track)" refs/heads >actual &&
+	test_cmp expected actual
+'
+
+cat >expected <<EOF
+>
+EOF
+
+test_expect_success 'Check upstream:trackshort format' '
+	git for-each-ref --format="%(upstream:trackshort)" refs/heads >actual &&
+	test_cmp expected actual
+'
+
+test_expect_success 'Check that :track[short] cannot be used with other atoms' '
+	test_must_fail git for-each-ref --format="%(refname:track)" 2>/dev/null &&
+	test_must_fail git for-each-ref --format="%(refname:trackshort)" 2>/dev/null
+'
+
 cat >expected <<EOF
 $(git rev-parse --short HEAD)
 EOF