[PATCH v13 23/27] stash: replace all `write-tree` child processes with API calls

[Thomas Gummerer <t.gummerer@xxxxxxxxx>]

From: Paul-Sebastian Ungureanu <ungureanupaulsebastian@xxxxxxxxx>

Avoid spawning write-tree child processes by replacing the calls with
in-core API calls.

Signed-off-by: Paul-Sebastian Ungureanu <ungureanupaulsebastian@xxxxxxxxx>
Signed-off-by: Thomas Gummerer <t.gummerer@xxxxxxxxx>
---
 builtin/stash--helper.c | 41 ++++++++++++-----------------------------
 1 file changed, 12 insertions(+), 29 deletions(-)

diff --git a/builtin/stash--helper.c b/builtin/stash--helper.c
index 4c51b58206..5f8c99c12f 100644
--- a/builtin/stash--helper.c
+++ b/builtin/stash--helper.c
@@ -943,9 +943,8 @@ static int save_untracked_files(struct stash_info *info, struct strbuf *msg,
 {
 	int ret = 0;
 	struct strbuf untracked_msg = STRBUF_INIT;
-	struct strbuf out = STRBUF_INIT;
 	struct child_process cp_upd_index = CHILD_PROCESS_INIT;
-	struct child_process cp_write_tree = CHILD_PROCESS_INIT;
+	struct index_state istate = { NULL };
 
 	cp_upd_index.git_cmd = 1;
 	argv_array_pushl(&cp_upd_index.args, "update-index", "-z", "--add",
@@ -960,15 +959,11 @@ static int save_untracked_files(struct stash_info *info, struct strbuf *msg,
 		goto done;
 	}
 
-	cp_write_tree.git_cmd = 1;
-	argv_array_push(&cp_write_tree.args, "write-tree");
-	argv_array_pushf(&cp_write_tree.env_array, "GIT_INDEX_FILE=%s",
-			 stash_index_path.buf);
-	if (pipe_command(&cp_write_tree, NULL, 0, &out, 0,NULL, 0)) {
+	if (write_index_as_tree(&info->u_tree, &istate, stash_index_path.buf, 0,
+				NULL)) {
 		ret = -1;
 		goto done;
 	}
-	get_oid_hex(out.buf, &info->u_tree);
 
 	if (commit_tree(untracked_msg.buf, untracked_msg.len,
 			&info->u_tree, NULL, &info->u_commit, NULL, NULL)) {
@@ -977,8 +972,8 @@ static int save_untracked_files(struct stash_info *info, struct strbuf *msg,
 	}
 
 done:
+	discard_index(&istate);
 	strbuf_release(&untracked_msg);
-	strbuf_release(&out);
 	remove_path(stash_index_path.buf);
 	return ret;
 }
@@ -987,11 +982,10 @@ static int stash_patch(struct stash_info *info, struct pathspec ps,
 		       struct strbuf *out_patch, int quiet)
 {
 	int ret = 0;
-	struct strbuf out = STRBUF_INIT;
 	struct child_process cp_read_tree = CHILD_PROCESS_INIT;
 	struct child_process cp_add_i = CHILD_PROCESS_INIT;
-	struct child_process cp_write_tree = CHILD_PROCESS_INIT;
 	struct child_process cp_diff_tree = CHILD_PROCESS_INIT;
+	struct index_state istate = { NULL };
 
 	remove_path(stash_index_path.buf);
 
@@ -1017,17 +1011,12 @@ static int stash_patch(struct stash_info *info, struct pathspec ps,
 	}
 
 	/* State of the working tree. */
-	cp_write_tree.git_cmd = 1;
-	argv_array_push(&cp_write_tree.args, "write-tree");
-	argv_array_pushf(&cp_write_tree.env_array, "GIT_INDEX_FILE=%s",
-			 stash_index_path.buf);
-	if (pipe_command(&cp_write_tree, NULL, 0, &out, 0,NULL, 0)) {
+	if (write_index_as_tree(&info->w_tree, &istate, stash_index_path.buf, 0,
+				NULL)) {
 		ret = -1;
 		goto done;
 	}
 
-	get_oid_hex(out.buf, &info->w_tree);
-
 	cp_diff_tree.git_cmd = 1;
 	argv_array_pushl(&cp_diff_tree.args, "diff-tree", "-p", "HEAD",
 			 oid_to_hex(&info->w_tree), "--", NULL);
@@ -1043,7 +1032,7 @@ static int stash_patch(struct stash_info *info, struct pathspec ps,
 	}
 
 done:
-	strbuf_release(&out);
+	discard_index(&istate);
 	remove_path(stash_index_path.buf);
 	return ret;
 }
@@ -1053,9 +1042,8 @@ static int stash_working_tree(struct stash_info *info, struct pathspec ps)
 	int ret = 0;
 	struct rev_info rev;
 	struct child_process cp_upd_index = CHILD_PROCESS_INIT;
-	struct child_process cp_write_tree = CHILD_PROCESS_INIT;
-	struct strbuf out = STRBUF_INIT;
 	struct strbuf diff_output = STRBUF_INIT;
+	struct index_state istate = { NULL };
 
 	init_revisions(&rev, NULL);
 
@@ -1095,20 +1083,15 @@ static int stash_working_tree(struct stash_info *info, struct pathspec ps)
 		goto done;
 	}
 
-	cp_write_tree.git_cmd = 1;
-	argv_array_push(&cp_write_tree.args, "write-tree");
-	argv_array_pushf(&cp_write_tree.env_array, "GIT_INDEX_FILE=%s",
-			 stash_index_path.buf);
-	if (pipe_command(&cp_write_tree, NULL, 0, &out, 0,NULL, 0)) {
+	if (write_index_as_tree(&info->w_tree, &istate, stash_index_path.buf, 0,
+				NULL)) {
 		ret = -1;
 		goto done;
 	}
 
-	get_oid_hex(out.buf, &info->w_tree);
-
 done:
+	discard_index(&istate);
 	UNLEAK(rev);
-	strbuf_release(&out);
 	object_array_clear(&rev.pending);
 	strbuf_release(&diff_output);
 	remove_path(stash_index_path.buf);
-- 
2.21.0.rc2.291.g17236886c5