vcpkg uses versions not in the baseline

[jsalvmaga]

Hi!

My project uses vcpkg (manifest mode) to fetch, among other packages, OpenCV 4.10.0#3, Python 3.12.9 and Pybind11 3.0.1. I've been using commit 5f4628b89f3f98cd9a0b43c27ded2aa53da1f790 of this repository as the default registry in my vcpkg-configuration.json, and it works like a charm, as it gets the exact versions I specify in the vcpkg.json. However, I've recently found out that said commit does not actually have the versions I'm requesting, as can be seen in the baseline. How is it possible that vcpkg is getting the versions I'm asking for, even though there weren't ports for them when that commit was created?

Just in case vcpkg was fetching them from a cache in my computer, I built a very simple vcpkg project in a virtual machine, and it still gets the requested versions. To reproduce it, you only have to:

1. Clone vcpkg's repository
2. Run the bootstrap batch file
3. Set the VCPKG_ROOT environment variable to the vcpkg project's root and add it to PATH
4. Create a new folder with the files below
5. Try to configure the project with CMake using the "dev" present

CMake should log that opencv4 4.10.0#3, python3 3.12.9 and pybind11 3.0.1 will be installed.

These are the project's files:

vcpkg.json

{
  "dependencies": [
      { "name": "opencv4", "version>=": "4.10.0#3" },
      { "name": "python3", "version>=": "3.12.9" },
      { "name": "pybind11", "version>=": "3.0.1" }
  ]
}

vcpkg-configuration.json

{
  "default-registry": {
    "kind": "git",
    "baseline": "5f4628b89f3f98cd9a0b43c27ded2aa53da1f790",
    "repository": "https://github.com/microsoft/vcpkg"
  },
  "registries": [
    {
      "kind": "artifact",
      "location": "https://github.com/microsoft/vcpkg-ce-catalog/archive/refs/heads/main.zip",
      "name": "microsoft"
    }
  ]
}

CMakePresets.json

{
  "version": 3,
  "configurePresets": [
    {
      "name": "dev",
      "generator": "Visual Studio 17 2022",
      "cacheVariables": {
        "CMAKE_BUILD_TYPE": "Release",
        "CMAKE_TOOLCHAIN_FILE": "$env{VCPKG_ROOT}/scripts/buildsystems/vcpkg.cmake"
      }
    }
  ],
  "buildPresets": [
    {
      "name": "dev",
      "configurePreset": "dev"
    }
  ]
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.26 FATAL_ERROR)

project(MyProj
  LANGUAGES CXX
  VERSION ${VERSION}
)

[Osyotr]

Git registries have reference option that defaults to HEAD. So what's happening is:

1. vcpkg fetches https://github.com/microsoft/vcpkg @ HEAD
2. Uses 5f4628b as a baseline
3. Then looks for { "name": "opencv4", "version>=": "4.10.0#3" }, etc in HEAD since the version in the baseline is older than requested.

[dg0yt]

The purpose of baseline is only to choose the minimum (default) version to be considered. By version>=, you select higher versions.

[jsalvmaga]

I've moved to the latest commit as of right now (aa2d37682e3318d93aef87efa7b0e88e81cd3d59), which has OpenCV 4.12, but vcpkg still fetches 4.10. If I'm using version>=, shouldn't it get 4.12 instead?

[dg0yt]

"Moved" how? To change version resolution, you must modify the baseline field.

[dg0yt]

If I'm using version>=, shouldn't it get 4.12 instead?

It should pick the lowest version which satifies this constraint and is newer than baseline.

[jsalvmaga]

Sorry, I meant that I checked out that commit, as my HEAD was in a commit from last November-December.

It should pick the lowest version which satifies this constraint and is newer than baseline.

Didn't you say that version>= can select higher versions? I've tried to use the commit I checked out as baseline and now it gets OpenCV 4.12, which is what I expected. However, if vcpkg is supposed to look in HEAD if the version I specify with version>= is not in the baseline, and HEAD has both 4.10 (which is the one I wrote in version>=) and 4.12, why doesn't it get 4.12? Is it that it gets the exact version that you request in version>= only if it can't be found in the baseline, only looking for higher versions in the baseline?

[Osyotr]

This is actually documented here https://learn.microsoft.com/en-us/vcpkg/users/versioning.concepts

[jsalvmaga]

Thanks, @Osyotr and @dg0yt ! That document really clarified everything for me!