merge(3p/git): Merge git subtree at v2.29.2 r/1890

This also bumps the stable nixpkgs to 20.09 as of 2020-11-21, because
there is some breakage in the git build related to the netrc
credentials helper which someone has taken care of in nixpkgs.

The stable channel is not used for anything other than git, so this
should be fine.

Change-Id: I3575a19dab09e1e9556cf8231d717de9890484fb

1 files changed, 24 insertions, 0 deletions

diff --git a/third_party/git/t/t2027-checkout-track.sh b/third_party/git/t/t2027-checkout-track.sh
new file mode 100755
index 000000000000..bcba1bf90c09
--- /dev/null
+++ b/third_party/git/t/t2027-checkout-track.sh
@@ -0,0 +1,24 @@
+#!/bin/sh
+
+test_description='tests for git branch --track'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+	test_commit one &&
+	test_commit two
+'
+
+test_expect_success 'checkout --track -b creates a new tracking branch' '
+	git checkout --track -b branch1 master &&
+	test $(git rev-parse --abbrev-ref HEAD) = branch1 &&
+	test $(git config --get branch.branch1.remote) = . &&
+	test $(git config --get branch.branch1.merge) = refs/heads/master
+'
+
+test_expect_success 'checkout --track -b rejects an extra path argument' '
+	test_must_fail git checkout --track -b branch2 master one.t 2>err &&
+	test_i18ngrep "cannot be used with updating paths" err
+'
+
+test_done