From 5b36ebf7b3ddf4c548b99aa4efc11d166e191b5b Mon Sep 17 00:00:00 2001
From: Hamid Reza Arzaghi <arzaghi@outlook.com>
Date: Thu, 10 Sep 2020 19:01:31 +0430
Subject: [PATCH 1/4] add test to cover the issue

---
 tests/std/tests/P0218R1_filesystem/test.cpp | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/tests/std/tests/P0218R1_filesystem/test.cpp b/tests/std/tests/P0218R1_filesystem/test.cpp
index df813ffa2a1..3a000d5df33 100644
--- a/tests/std/tests/P0218R1_filesystem/test.cpp
+++ b/tests/std/tests/P0218R1_filesystem/test.cpp
@@ -3570,6 +3570,7 @@ void test_temp_directory_path() {
 void test_create_directory() {
     const test_temp_directory tempDir("create_directory"sv);
     const path p = tempDir.directoryPath / L"__std.c++17.filesystem.create_directory"sv;
+    const path emptyPath{};
 
     // test happy
     {
@@ -3608,6 +3609,17 @@ void test_create_directory() {
         }
     }
 
+    // test empty path
+    {
+        try {
+            // create_directory should throw for empty paths
+            create_directories(emptyPath);
+            assert(false);
+        } catch (const filesystem_error&) {
+            assert(true);
+        }
+    }
+
     // test VSO-654638 where create_directory(p, existing_p) was doing copy_symlink behavior
     {
         error_code ec;

From 44a5bf56a73c885d0145dfcb8f3cc8984e183bb8 Mon Sep 17 00:00:00 2001
From: Hamid Reza Arzaghi <arzaghi@outlook.com>
Date: Thu, 10 Sep 2020 19:11:13 +0430
Subject: [PATCH 2/4] create_directory throw on empty path

---
 stl/inc/filesystem | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/stl/inc/filesystem b/stl/inc/filesystem
index a2f4bd1dd09..343fb2a1e66 100644
--- a/stl/inc/filesystem
+++ b/stl/inc/filesystem
@@ -3750,6 +3750,10 @@ namespace filesystem {
 
     // FUNCTION create_directories
     inline bool create_directories(const path& _Path, error_code& _Ec) {
+        if (_Path.empty()) {
+            _Throw_fs_error("create_directories", _Make_ec(__std_win_error::_Invalid_parameter), _Path);
+        }
+
         _Ec.clear(); // for exception safety
         const wstring& _Text = _Path.native();
         wstring _Tmp;

From d63731f4a1f1e4f1a7a60d1515f27a7bf462223e Mon Sep 17 00:00:00 2001
From: Hamid Reza Arzaghi <arzaghi@outlook.com>
Date: Fri, 11 Sep 2020 16:22:11 +0430
Subject: [PATCH 3/4] create_directory throw for empty paths

---
 stl/inc/filesystem | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/stl/inc/filesystem b/stl/inc/filesystem
index 343fb2a1e66..da6f941f9c6 100644
--- a/stl/inc/filesystem
+++ b/stl/inc/filesystem
@@ -3751,7 +3751,8 @@ namespace filesystem {
     // FUNCTION create_directories
     inline bool create_directories(const path& _Path, error_code& _Ec) {
         if (_Path.empty()) {
-            _Throw_fs_error("create_directories", _Make_ec(__std_win_error::_Invalid_parameter), _Path);
+            _Ec = _Make_ec(__std_win_error::_Path_not_found);
+            return false;
         }
 
         _Ec.clear(); // for exception safety

From 20fc68dc7123a34a5a8c46cee811f275a14cda9e Mon Sep 17 00:00:00 2001
From: Hamid Reza Arzaghi <arzaghi@outlook.com>
Date: Wed, 23 Sep 2020 06:41:17 +0330
Subject: [PATCH 4/4] apply suggestions to the test

---
 tests/std/tests/P0218R1_filesystem/test.cpp | 17 +++++------------
 1 file changed, 5 insertions(+), 12 deletions(-)

diff --git a/tests/std/tests/P0218R1_filesystem/test.cpp b/tests/std/tests/P0218R1_filesystem/test.cpp
index 3a000d5df33..0ff4f084c32 100644
--- a/tests/std/tests/P0218R1_filesystem/test.cpp
+++ b/tests/std/tests/P0218R1_filesystem/test.cpp
@@ -3570,7 +3570,6 @@ void test_temp_directory_path() {
 void test_create_directory() {
     const test_temp_directory tempDir("create_directory"sv);
     const path p = tempDir.directoryPath / L"__std.c++17.filesystem.create_directory"sv;
-    const path emptyPath{};
 
     // test happy
     {
@@ -3609,17 +3608,6 @@ void test_create_directory() {
         }
     }
 
-    // test empty path
-    {
-        try {
-            // create_directory should throw for empty paths
-            create_directories(emptyPath);
-            assert(false);
-        } catch (const filesystem_error&) {
-            assert(true);
-        }
-    }
-
     // test VSO-654638 where create_directory(p, existing_p) was doing copy_symlink behavior
     {
         error_code ec;
@@ -3681,6 +3669,11 @@ void test_create_dirs_and_remove_all() {
     remove_all(badPath, ec);
     EXPECT(good(ec));
 
+    // test GH-1283 create_directories() should throw for empty paths
+    EXPECT(throws_filesystem_error([] { create_directories(path{}); }, "create_directories", path{}));
+    EXPECT(create_directories(path{}, ec) == false);
+    EXPECT(bad(ec));
+
     // test that normalization isn't done first
     auto dots = r / L"a/../b/../c"sv;
     EXPECT(create_directories(dots));