[GSoC RFC PATCH v4 4/4] repo: add field layout.shallow

[Lucas Seiki Oshiro <lucasseikioshiro@gmail.com>]

This commit is part of the series that introduces the new subcommand
git-repo-info.

The flag `--is-shallow-repository` from git-rev-parse is used for
retrieving whether the repository is shallow. This way, it is used for
querying repository metadata, fitting in the purpose of git-repo-info.

Then, add a new field `layout.shallow` to the git-repo-info subcommand
containing that information.

Helped-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Helped-by: Junio C Hamano <gitster@pobox.com>
Helped-by: Justin Tobler <jltobler@gmail.com>
Mentored-by: Karthik Nayak <karthik.188@gmail.com>
Mentored-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Lucas Seiki Oshiro <lucasseikioshiro@gmail.com>
---
 Documentation/git-repo.adoc |  1 +
 builtin/repo.c              |  7 +++++++
 t/t1900-repo.sh             | 22 ++++++++++++++++++++++
 3 files changed, 30 insertions(+)

diff --git a/Documentation/git-repo.adoc b/Documentation/git-repo.adoc
index db185c5c91..864868993b 100644
--- a/Documentation/git-repo.adoc
+++ b/Documentation/git-repo.adoc
@@ -52,6 +52,7 @@ Reference-related data:
 `layout`::
 Information about the how the current repository is represented:
 * `bare`: `true` if this is a bare repository, otherwise `false`.
+* `shallow`: `true` if this is a shallow repository, otherwise `false`.
 
 SEE ALSO
 --------
diff --git a/builtin/repo.c b/builtin/repo.c
index 5eefe06918..d75417a48b 100644
--- a/builtin/repo.c
+++ b/builtin/repo.c
@@ -5,6 +5,7 @@
 #include "strbuf.h"
 #include "refs.h"
 #include "environment.h"
+#include "shallow.h"
 
 typedef void add_field_fn(struct strbuf *buf, struct repository *repo);
 
@@ -39,9 +40,15 @@ static void add_layout_bare(struct strbuf *buf, struct repository *repo UNUSED)
 	add_bool(buf, "layout.bare", is_bare_repository());
 }
 
+static void add_layout_shallow(struct strbuf *buf, struct repository *repo)
+{
+	add_bool(buf, "layout.shallow", is_repository_shallow(repo));
+}
+
 // repo_info_fields keys should be in lexicographical order
 static const struct field repo_info_fields[] = {
 	{"layout.bare", add_layout_bare},
+	{"layout.shallow", add_layout_shallow},
 	{"references.format", add_references_format},
 };
 
diff --git a/t/t1900-repo.sh b/t/t1900-repo.sh
index 6155e275b5..e0e2393247 100755
--- a/t/t1900-repo.sh
+++ b/t/t1900-repo.sh
@@ -42,6 +42,20 @@ test_repo_info 'bare repository = false is retrieved correctly' '
 test_repo_info 'bare repository = true is retrieved correctly' '
 	git init --bare repo' 'layout.bare' 'true'
 
+test_repo_info 'shallow repository = false is retrieved correctly' '
+	git init repo' 'layout.shallow' 'false'
+
+test_repo_info 'shallow repository = true is retrieved correctly' '
+	git init remote &&
+	cd remote &&
+	echo x >x &&
+	git add x &&
+	git commit -m x &&
+	cd .. &&
+	git clone --depth 1 "file://$PWD/remote" repo &&
+	rm -rf remote
+	' 'layout.shallow' 'true'
+
 test_expect_success "only one value is returned if the same key is requested twice" '
 	echo "references.format" > expected &&
 	git rev-parse --show-ref-format > ref-format &&
@@ -50,4 +64,12 @@ test_expect_success "only one value is returned if the same key is requested twi
 	test_cmp expected actual
 '
 
+test_expect_success 'output is returned correctly when two keys are requested' '
+	test_when_finished "rm -f expect" &&
+	printf "layout.bare\nfalseQlayout.shallow\nfalseQ" >expect &&
+	git repo info layout.shallow layout.bare >output &&
+	nul_to_q <output >actual &&
+	test_cmp expect actual
+'
+
 test_done
-- 
2.39.5 (Apple Git-154)