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, 90 insertions, 0 deletions

diff --git a/third_party/git/t/t2405-worktree-submodule.sh b/third_party/git/t/t2405-worktree-submodule.sh
new file mode 100755
index 000000000000..e1b2bfd87e0d
--- /dev/null
+++ b/third_party/git/t/t2405-worktree-submodule.sh
@@ -0,0 +1,90 @@
+#!/bin/sh
+
+test_description='Combination of submodules and multiple worktrees'
+
+. ./test-lib.sh
+
+base_path=$(pwd -P)
+
+test_expect_success 'setup: create origin repos'  '
+	git init origin/sub &&
+	test_commit -C origin/sub file1 &&
+	git init origin/main &&
+	test_commit -C origin/main first &&
+	git -C origin/main submodule add ../sub &&
+	git -C origin/main commit -m "add sub" &&
+	test_commit -C origin/sub "file1 updated" file1 file1updated file1updated &&
+	git -C origin/main/sub pull &&
+	git -C origin/main add sub &&
+	git -C origin/main commit -m "sub updated"
+'
+
+test_expect_success 'setup: clone superproject to create main worktree' '
+	git clone --recursive "$base_path/origin/main" main
+'
+
+rev1_hash_main=$(git --git-dir=origin/main/.git show --pretty=format:%h -q "HEAD~1")
+rev1_hash_sub=$(git --git-dir=origin/sub/.git show --pretty=format:%h -q "HEAD~1")
+
+test_expect_success 'add superproject worktree' '
+	git -C main worktree add "$base_path/worktree" "$rev1_hash_main"
+'
+
+test_expect_failure 'submodule is checked out just after worktree add' '
+	git -C worktree diff --submodule master"^!" >out &&
+	grep "file1 updated" out
+'
+
+test_expect_success 'add superproject worktree and initialize submodules' '
+	git -C main worktree add "$base_path/worktree-submodule-update" "$rev1_hash_main" &&
+	git -C worktree-submodule-update submodule update
+'
+
+test_expect_success 'submodule is checked out just after submodule update in linked worktree' '
+	git -C worktree-submodule-update diff --submodule master"^!" >out &&
+	grep "file1 updated" out
+'
+
+test_expect_success 'add superproject worktree and manually add submodule worktree' '
+	git -C main worktree add "$base_path/linked_submodule" "$rev1_hash_main" &&
+	git -C main/sub worktree add "$base_path/linked_submodule/sub" "$rev1_hash_sub"
+'
+
+test_expect_success 'submodule is checked out after manually adding submodule worktree' '
+	git -C linked_submodule diff --submodule master"^!" >out &&
+	grep "file1 updated" out
+'
+
+test_expect_success 'checkout --recurse-submodules uses $GIT_DIR for submodules in a linked worktree' '
+	git -C main worktree add "$base_path/checkout-recurse" --detach  &&
+	git -C checkout-recurse submodule update --init &&
+	echo "gitdir: ../../main/.git/worktrees/checkout-recurse/modules/sub" >expect-gitfile &&
+	cat checkout-recurse/sub/.git >actual-gitfile &&
+	test_cmp expect-gitfile actual-gitfile &&
+	git -C main/sub rev-parse HEAD >expect-head-main &&
+	git -C checkout-recurse checkout --recurse-submodules HEAD~1 &&
+	cat checkout-recurse/sub/.git >actual-gitfile &&
+	git -C main/sub rev-parse HEAD >actual-head-main &&
+	test_cmp expect-gitfile actual-gitfile &&
+	test_cmp expect-head-main actual-head-main
+'
+
+test_expect_success 'core.worktree is removed in $GIT_DIR/modules/<name>/config, not in $GIT_COMMON_DIR/modules/<name>/config' '
+	echo "../../../sub" >expect-main &&
+	git -C main/sub config --get core.worktree >actual-main &&
+	test_cmp expect-main actual-main &&
+	echo "../../../../../../checkout-recurse/sub" >expect-linked &&
+	git -C checkout-recurse/sub config --get core.worktree >actual-linked &&
+	test_cmp expect-linked actual-linked &&
+	git -C checkout-recurse checkout --recurse-submodules first &&
+	test_expect_code 1 git -C main/.git/worktrees/checkout-recurse/modules/sub config --get core.worktree >linked-config &&
+	test_must_be_empty linked-config &&
+	git -C main/sub config --get core.worktree >actual-main &&
+	test_cmp expect-main actual-main
+'
+
+test_expect_success 'unsetting core.worktree does not prevent running commands directly against the submodule repository' '
+	git -C main/.git/worktrees/checkout-recurse/modules/sub log
+'
+
+test_done