From d1fd1353f85201f4bb5e9c387917ee203032a9d2 Mon Sep 17 00:00:00 2001
From: Andrew Ayer <agwa@andrewayer.name>
Date: Sat, 25 Jan 2020 10:16:20 -0500
Subject: [PATCH] Execute git checkout in batches to avoid overlong argument
 lists

Closes: #195
Closes: #194
Closes: #150
---
 commands.cpp | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/commands.cpp b/commands.cpp
index d25c4cc..9c19b3c 100644
--- a/commands.cpp
+++ b/commands.cpp
@@ -183,15 +183,19 @@ static void deconfigure_git_filters (const char* key_name)
 	}
 }
 
-static bool git_checkout (const std::vector<std::string>& paths)
+static bool git_checkout_batch (std::vector<std::string>::const_iterator paths_begin, std::vector<std::string>::const_iterator paths_end)
 {
+	if (paths_begin == paths_end) {
+		return true;
+	}
+
 	std::vector<std::string>	command;
 
 	command.push_back("git");
 	command.push_back("checkout");
 	command.push_back("--");
 
-	for (std::vector<std::string>::const_iterator path(paths.begin()); path != paths.end(); ++path) {
+	for (auto path(paths_begin); path != paths_end; ++path) {
 		command.push_back(*path);
 	}
 
@@ -202,6 +206,18 @@ static bool git_checkout (const std::vector<std::string>& paths)
 	return true;
 }
 
+static bool git_checkout (const std::vector<std::string>& paths)
+{
+	auto paths_begin(paths.begin());
+	while (paths.end() - paths_begin >= 100) {
+		if (!git_checkout_batch(paths_begin, paths_begin + 100)) {
+			return false;
+		}
+		paths_begin += 100;
+	}
+	return git_checkout_batch(paths_begin, paths.end());
+}
+
 static bool same_key_name (const char* a, const char* b)
 {
 	return (!a && !b) || (a && b && std::strcmp(a, b) == 0);