Re: [PATCH v4 1/4] checkout: factor out functions to new lib file

Factor the functions out, so they can be re-used from other places.  In
particular these functions will be re-used in builtin/worktree.c to make
git worktree add dwim more.

While there add some docs to the function.

Signed-off-by: Thomas Gummerer <redacted>
---
 Makefile           |  1 +
 builtin/checkout.c | 41 +----------------------------------------
 checkout.c         | 42 ++++++++++++++++++++++++++++++++++++++++++
 checkout.h         | 13 +++++++++++++
 4 files changed, 57 insertions(+), 40 deletions(-)
 create mode 100644 checkout.c
 create mode 100644 checkout.h

diff --git a/Makefile b/Makefile
index cd75985991..8d603c7443 100644
--- a/Makefile
+++ b/Makefile

@@ -757,6 +757,7 @@ LIB_OBJS += branch.o
 LIB_OBJS += bulk-checkin.o
 LIB_OBJS += bundle.o
 LIB_OBJS += cache-tree.o
+LIB_OBJS += checkout.o
 LIB_OBJS += color.o
 LIB_OBJS += column.o
 LIB_OBJS += combine-diff.o

diff --git a/builtin/checkout.c b/builtin/checkout.c
index fc4f8fd2ea..9e1cfd10b3 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c

@@ -1,5 +1,6 @@
 #include "builtin.h"
 #include "config.h"
+#include "checkout.h"
 #include "lockfile.h"
 #include "parse-options.h"
 #include "refs.h"

diff --git a/checkout.c b/checkout.c
new file mode 100644
index 0000000000..b0c744d37a
--- /dev/null
+++ b/checkout.c

@@ -0,0 +1,42 @@
+#include "cache.h"
+#include "remote.h"