scalar: include in standard Git build & installation

Move 'scalar' out of 'contrib/' and into the root of the Git tree. The goal
of this change is to build 'scalar' as part of the standard Git build &
install processes.

This patch includes both the physical move of Scalar's files out of
'contrib/' ('scalar.c', 'scalar.txt', and 't9xxx-scalar.sh'), and the
changes to the build definitions in 'Makefile' and 'CMakelists.txt' to
accommodate the new program.

At a high level, Scalar is built so that:
- there is a 'scalar-objs' target (similar to those created in 029bac01a8
  (Makefile: add {program,xdiff,test,git,fuzz}-objs & objects targets,
  2021-02-23)) for debugging purposes.
- it appears in the root of the install directory (rather than the
  gitexecdir).
- it is included in the 'bin-wrappers/' directory for use in tests.
- it receives a platform-specific executable suffix (e.g., '.exe'), if
  applicable.
- 'scalar.txt' is installed as 'man1' documentation.
- the 'clean' target removes the 'scalar' executable.

Additionally, update the root level '.gitignore' file to ignore the Scalar
executable.

Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 210 insertions, 0 deletions

diff --git a/t/t9210-scalar.sh b/t/t9210-scalar.sh
new file mode 100755
index 0000000000..14ca575a21
--- /dev/null
+++ b/t/t9210-scalar.sh
@@ -0,0 +1,210 @@
+#!/bin/sh
+
+test_description='test the `scalar` command'
+
+. ./test-lib.sh
+
+GIT_TEST_MAINT_SCHEDULER="crontab:test-tool crontab cron.txt,launchctl:true,schtasks:true"
+export GIT_TEST_MAINT_SCHEDULER
+
+test_expect_success 'scalar shows a usage' '
+	test_expect_code 129 scalar -h
+'
+
+test_expect_success 'scalar invoked on enlistment root' '
+	test_when_finished rm -rf test src deeper &&
+
+	for enlistment_root in test src deeper/test
+	do
+		git init ${enlistment_root}/src &&
+
+		# Register
+		scalar register ${enlistment_root} &&
+		scalar list >out &&
+		grep "$(pwd)/${enlistment_root}/src\$" out &&
+
+		# Delete (including enlistment root)
+		scalar delete $enlistment_root &&
+		test_path_is_missing $enlistment_root &&
+		scalar list >out &&
+		! grep "^$(pwd)/${enlistment_root}/src\$" out || return 1
+	done
+'
+
+test_expect_success 'scalar invoked on enlistment src repo' '
+	test_when_finished rm -rf test src deeper &&
+
+	for enlistment_root in test src deeper/test
+	do
+		git init ${enlistment_root}/src &&
+
+		# Register
+		scalar register ${enlistment_root}/src &&
+		scalar list >out &&
+		grep "$(pwd)/${enlistment_root}/src\$" out &&
+
+		# Delete (will not include enlistment root)
+		scalar delete ${enlistment_root}/src &&
+		test_path_is_dir $enlistment_root &&
+		scalar list >out &&
+		! grep "^$(pwd)/${enlistment_root}/src\$" out || return 1
+	done
+'
+
+test_expect_success 'scalar invoked when enlistment root and repo are the same' '
+	test_when_finished rm -rf test src deeper &&
+
+	for enlistment_root in test src deeper/test
+	do
+		git init ${enlistment_root} &&
+
+		# Register
+		scalar register ${enlistment_root} &&
+		scalar list >out &&
+		grep "$(pwd)/${enlistment_root}\$" out &&
+
+		# Delete (will not include enlistment root)
+		scalar delete ${enlistment_root} &&
+		test_path_is_missing $enlistment_root &&
+		scalar list >out &&
+		! grep "^$(pwd)/${enlistment_root}\$" out &&
+
+		# Make sure we did not accidentally delete the trash dir
+		test_path_is_dir "$TRASH_DIRECTORY" || return 1
+	done
+'
+
+test_expect_success 'scalar repo search respects GIT_CEILING_DIRECTORIES' '
+	test_when_finished rm -rf test &&
+
+	git init test/src &&
+	mkdir -p test/src/deep &&
+	GIT_CEILING_DIRECTORIES="$(pwd)/test/src" &&
+	! scalar register test/src/deep 2>err &&
+	grep "not a git repository" err
+'
+
+test_expect_success 'scalar enlistments need a worktree' '
+	test_when_finished rm -rf bare test &&
+
+	git init --bare bare/src &&
+	! scalar register bare/src 2>err &&
+	grep "Scalar enlistments require a worktree" err &&
+
+	git init test/src &&
+	! scalar register test/src/.git 2>err &&
+	grep "Scalar enlistments require a worktree" err
+'
+
+test_expect_success FSMONITOR_DAEMON 'scalar register starts fsmon daemon' '
+	git init test/src &&
+	test_must_fail git -C test/src fsmonitor--daemon status &&
+	scalar register test/src &&
+	git -C test/src fsmonitor--daemon status &&
+	test_cmp_config -C test/src true core.fsmonitor
+'
+
+test_expect_success 'scalar unregister' '
+	git init vanish/src &&
+	scalar register vanish/src &&
+	git config --get --global --fixed-value \
+		maintenance.repo "$(pwd)/vanish/src" &&
+	scalar list >scalar.repos &&
+	grep -F "$(pwd)/vanish/src" scalar.repos &&
+	rm -rf vanish/src/.git &&
+	scalar unregister vanish &&
+	test_must_fail git config --get --global --fixed-value \
+		maintenance.repo "$(pwd)/vanish/src" &&
+	scalar list >scalar.repos &&
+	! grep -F "$(pwd)/vanish/src" scalar.repos
+'
+
+test_expect_success 'set up repository to clone' '
+	test_commit first &&
+	test_commit second &&
+	test_commit third &&
+	git switch -c parallel first &&
+	mkdir -p 1/2 &&
+	test_commit 1/2/3 &&
+	git config uploadPack.allowFilter true &&
+	git config uploadPack.allowAnySHA1InWant true
+'
+
+test_expect_success 'scalar clone' '
+	second=$(git rev-parse --verify second:second.t) &&
+	scalar clone "file://$(pwd)" cloned --single-branch &&
+	(
+		cd cloned/src &&
+
+		git config --get --global --fixed-value maintenance.repo \
+			"$(pwd)" &&
+
+		git for-each-ref --format="%(refname)" refs/remotes/origin/ >actual &&
+		echo "refs/remotes/origin/parallel" >expect &&
+		test_cmp expect actual &&
+
+		test_path_is_missing 1/2 &&
+		test_must_fail git rev-list --missing=print $second &&
+		git rev-list $second &&
+		git cat-file blob $second >actual &&
+		echo "second" >expect &&
+		test_cmp expect actual
+	)
+'
+
+test_expect_success 'scalar reconfigure' '
+	git init one/src &&
+	scalar register one &&
+	git -C one/src config core.preloadIndex false &&
+	scalar reconfigure one &&
+	test true = "$(git -C one/src config core.preloadIndex)" &&
+	git -C one/src config core.preloadIndex false &&
+	scalar reconfigure -a &&
+	test true = "$(git -C one/src config core.preloadIndex)"
+'
+
+test_expect_success 'scalar delete without enlistment shows a usage' '
+	test_expect_code 129 scalar delete
+'
+
+test_expect_success 'scalar delete with enlistment' '
+	scalar delete cloned &&
+	test_path_is_missing cloned
+'
+
+test_expect_success 'scalar supports -c/-C' '
+	test_when_finished "scalar delete sub" &&
+	git init sub &&
+	scalar -C sub -c status.aheadBehind=bogus register &&
+	test -z "$(git -C sub config --local status.aheadBehind)" &&
+	test true = "$(git -C sub config core.preloadIndex)"
+'
+
+test_expect_success '`scalar [...] <dir>` errors out when dir is missing' '
+	! scalar run config cloned 2>err &&
+	grep "cloned. does not exist" err
+'
+
+SQ="'"
+test_expect_success UNZIP 'scalar diagnose' '
+	scalar clone "file://$(pwd)" cloned --single-branch &&
+	git repack &&
+	echo "$(pwd)/.git/objects/" >>cloned/src/.git/objects/info/alternates &&
+	test_commit -C cloned/src loose &&
+	scalar diagnose cloned >out 2>err &&
+	grep "Available space" out &&
+	sed -n "s/.*$SQ\\(.*\\.zip\\)$SQ.*/\\1/p" <err >zip_path &&
+	zip_path=$(cat zip_path) &&
+	test -n "$zip_path" &&
+	"$GIT_UNZIP" -v "$zip_path" &&
+	folder=${zip_path%.zip} &&
+	test_path_is_missing "$folder" &&
+	"$GIT_UNZIP" -p "$zip_path" diagnostics.log >out &&
+	test_file_not_empty out &&
+	"$GIT_UNZIP" -p "$zip_path" packs-local.txt >out &&
+	grep "$(pwd)/.git/objects" out &&
+	"$GIT_UNZIP" -p "$zip_path" objects-local.txt >out &&
+	grep "^Total: [1-9]" out
+'
+
+test_done