Merge branch 'jc/push-to-checkout'

Extending the js/push-to-deploy topic, the behaviour of "git push"
when updating the working tree and the index with an update to the
branch that is checked out can be tweaked by push-to-checkout hook.

* jc/push-to-checkout:
  receive-pack: support push-to-checkout hook
  receive-pack: refactor updateInstead codepath

1 files changed, 45 insertions, 25 deletions

diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index 4e85e25..e0ce78e 100644
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -743,7 +743,9 @@ static int update_shallow_ref(struct command *cmd, struct shallow_info *si)
 	return 0;
 }
 
-static const char *update_worktree(unsigned char *sha1)
+static const char *push_to_deploy(unsigned char *sha1,
+				  struct argv_array *env,
+				  const char *work_tree)
 {
 	const char *update_refresh[] = {
 		"update-index", "-q", "--ignore-submodules", "--refresh", NULL
@@ -758,69 +760,87 @@ static const char *update_worktree(unsigned char *sha1)
 	const char *read_tree[] = {
 		"read-tree", "-u", "-m", NULL, NULL
 	};
-	const char *work_tree = git_work_tree_cfg ? git_work_tree_cfg : "..";
-	struct argv_array env = ARGV_ARRAY_INIT;
 	struct child_process child = CHILD_PROCESS_INIT;
 
-	if (is_bare_repository())
-		return "denyCurrentBranch = updateInstead needs a worktree";
-
-	argv_array_pushf(&env, "GIT_DIR=%s", absolute_path(get_git_dir()));
-
 	child.argv = update_refresh;
-	child.env = env.argv;
+	child.env = env->argv;
 	child.dir = work_tree;
 	child.no_stdin = 1;
 	child.stdout_to_stderr = 1;
 	child.git_cmd = 1;
-	if (run_command(&child)) {
-		argv_array_clear(&env);
+	if (run_command(&child))
 		return "Up-to-date check failed";
-	}
 
 	/* run_command() does not clean up completely; reinitialize */
 	child_process_init(&child);
 	child.argv = diff_files;
-	child.env = env.argv;
+	child.env = env->argv;
 	child.dir = work_tree;
 	child.no_stdin = 1;
 	child.stdout_to_stderr = 1;
 	child.git_cmd = 1;
-	if (run_command(&child)) {
-		argv_array_clear(&env);
+	if (run_command(&child))
 		return "Working directory has unstaged changes";
-	}
 
 	child_process_init(&child);
 	child.argv = diff_index;
-	child.env = env.argv;
+	child.env = env->argv;
 	child.no_stdin = 1;
 	child.no_stdout = 1;
 	child.stdout_to_stderr = 0;
 	child.git_cmd = 1;
-	if (run_command(&child)) {
-		argv_array_clear(&env);
+	if (run_command(&child))
 		return "Working directory has staged changes";
-	}
 
 	read_tree[3] = sha1_to_hex(sha1);
 	child_process_init(&child);
 	child.argv = read_tree;
-	child.env = env.argv;
+	child.env = env->argv;
 	child.dir = work_tree;
 	child.no_stdin = 1;
 	child.no_stdout = 1;
 	child.stdout_to_stderr = 0;
 	child.git_cmd = 1;
-	if (run_command(&child)) {
-		argv_array_clear(&env);
+	if (run_command(&child))
 		return "Could not update working tree to new HEAD";
-	}
 
-	argv_array_clear(&env);
 	return NULL;
 }
 
+static const char *push_to_checkout_hook = "push-to-checkout";
+
+static const char *push_to_checkout(unsigned char *sha1,
+				    struct argv_array *env,
+				    const char *work_tree)
+{
+	argv_array_pushf(env, "GIT_WORK_TREE=%s", absolute_path(work_tree));
+	if (run_hook_le(env->argv, push_to_checkout_hook,
+			sha1_to_hex(sha1), NULL))
+		return "push-to-checkout hook declined";
+	else
+		return NULL;
+}
+
+static const char *update_worktree(unsigned char *sha1)
+{
+	const char *retval;
+	const char *work_tree = git_work_tree_cfg ? git_work_tree_cfg : "..";
+	struct argv_array env = ARGV_ARRAY_INIT;
+
+	if (is_bare_repository())
+		return "denyCurrentBranch = updateInstead needs a worktree";
+
+	argv_array_pushf(&env, "GIT_DIR=%s", absolute_path(get_git_dir()));
+
+	if (!find_hook(push_to_checkout_hook))
+		retval = push_to_deploy(sha1, &env, work_tree);
+	else
+		retval = push_to_checkout(sha1, &env, work_tree);
+
+	argv_array_clear(&env);
+	return retval;
+}
+
 static const char *update(struct command *cmd, struct shallow_info *si)
 {
 	const char *name = cmd->ref_name;