[vcpkg] Make Filesystem::remove_all faster #7570

I added benchmarks to measure how fast the parallel remove_all code was
-- it turns out, about 3x slower than stdfs::remove_all. Since this was
the case, I removed all of the parallelism and rewrote it serially, and
ended up about 30% faster than stdfs::remove_all (in addition to
supporting symlinks).

In addition, I did the following three orthogonal changes:
  - simplified the work queue, basing it on Billy O'Neal's idea
  - Fix warnings on older versions of compilers in tests, by splitting
    the pragmas out of pch.h.
  - Ran clang-format on some files

In fixing up remove_all, the following changes were made:
  - On Windows, regular symlinks and directory symlinks are distinct;
    as an example, to remove directory symlinks (and junctions, for that
    matter), one must use RemoveDirectory. Only on Windows, I added new
    `file_type` and `file_status` types, with `file_type` including a new
    `directory_symlink` enumerator, and `file_status` being exactly the
    same as the old one except using the new `file_type`. On Unix, I
    didn't make that change since they don't make a distinction.
  - I added new `symlink_status` and `status` functions which use the
    new `file_status` on Windows.
  - I made `Filesystem::exists` call `fs::exists(status(p))`, as opposed
    to the old version which called `stdfs::exists` directly.
  - Added benchmarks to `vcpkg-test/files.cpp`. They test the
    performance of `remove_all` on small directories (~20 files), with
    symlinks and without, and on large directories (~2000 files), with
    symlinks and without.

1 files changed, 7 insertions, 7 deletions

diff --git a/toolsrc/src/vcpkg.cpp b/toolsrc/src/vcpkg.cpp
index 46ec8c013..3fdbd0d3e 100644
--- a/toolsrc/src/vcpkg.cpp
+++ b/toolsrc/src/vcpkg.cpp
@@ -125,12 +125,8 @@ static void inner(const VcpkgCmdArguments& args)
 
     auto default_vs_path = System::get_environment_variable("VCPKG_VISUAL_STUDIO_PATH").value_or("");
 
-
-
-    const Expected<VcpkgPaths> expected_paths = VcpkgPaths::create(vcpkg_root_dir, 
-                                                                   vcpkg_scripts_root_dir,
-                                                                   default_vs_path, 
-                                                                   args.overlay_triplets.get());
+    const Expected<VcpkgPaths> expected_paths =
+        VcpkgPaths::create(vcpkg_root_dir, vcpkg_scripts_root_dir, default_vs_path, args.overlay_triplets.get());
     Checks::check_exit(VCPKG_LINE_INFO,
                        !expected_paths.error(),
                        "Error: Invalid vcpkg root directory %s: %s",
@@ -143,7 +139,11 @@ static void inner(const VcpkgCmdArguments& args)
 #else
     const int exit_code = chdir(paths.root.c_str());
 #endif
-    Checks::check_exit(VCPKG_LINE_INFO, exit_code == 0, "Changing the working directory to the vcpkg root directory failed. Did you incorrectly define the VCPKG_ROOT environment variable, or did you mistakenly create a file named .vcpkg-root somewhere?");
+    Checks::check_exit(
+        VCPKG_LINE_INFO,
+        exit_code == 0,
+        "Changing the working directory to the vcpkg root directory failed. Did you incorrectly define the VCPKG_ROOT "
+        "environment variable, or did you mistakenly create a file named .vcpkg-root somewhere?");
 
     if (args.command == "install" || args.command == "remove" || args.command == "export" || args.command == "update")
     {