We are pleased to announce that Conan 1.51 is out and comes with some significant new features and bug fixes. For example, we added support in conan.tools.files.download to get files from the local file system. Also, now the MSBuildDeps generator has support for components. We have made some improvements to the CMakePresets support. We added a new MesonDeps generator. Finally, we continue to work on the transition to Conan 2.0. This release brings several fixes to make the migration easier.

Support for files in the local file system in conan.tools.files.download

Starting in Conan 1.51, the download tool can reference files from the local file system. That means that conan.tools.files.get() will also work with local files. To use it in your recipes, reference the file you want to get or download using the file:///<location> syntax like this:

from conan import ConanFile
from conan.tools.files import get

class MylibConan(ConanFile):

    def source(self):
        get(self, "file:///path_to_folder/source.zip")
        # or if you want to use download...
        download(self, "file:///path_to_folder/main.cpp")

To learn more about these tools, please check the Conan documentation.

Components support in MSBuildDeps

This release brings component support for the MSBuildDeps generator. Now, for Conan packages that use components, this generator will create separate property files for each component. That means that you can customize those property files to just include what you need. For example, if you are depending directly on a package that has components such as boost but you just want to use the boost filesystem and chrono components, you can easily customize the property file in the generate() method. Let’s see an example:

import textwrap
from conan import ConanFile
from conan.tools.microsoft import MSBuildDeps
from conan.tools.files import save

class MyappConan(ConanFile):
    name = "myapp"
    version = "1.0"

    def generate(self):
        deps = MSBuildDeps(self)
        # overwrite the generated conan_boost.props
        # with just the components
        # we want to use instead of all of them
        component_deps = textwrap.dedent(r"""
          <?xml version="1.0" ?>
          <Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="4.0">
            <ImportGroup Label="PropertySheets">
              <Import Condition="'$(conan_boost_chrono_props_imported)' != 'True'" Project="conan_boost_chrono.props"/>
              <Import Condition="'$(conan_boost_filesystem_props_imported)' != 'True'" Project="conan_boost_filesystem.props"/>
        save(self, "conan_boost.props", component_deps)

Improvements in CMakePresets integration

We continue to improve the CMakePresets support in Conan. This release adds a couple of features:

  • The CMakePresets.json adds toolset and architecture items when using Ninja generator and the msvc compiler. This will make that Visual Studio can set the correct compiler automatically

  • There is a new conf item named tools.cmake.cmaketoolchain.presets:max_schema_version to define which schema version is used for the files CMakePresets.json and CMakeUserPresets.json. By default, the version schema of the generated CMakeUserPresets.json is 4 and the schema for the CMakePresets.json is 3, so be aware that they require CMake >= 3.23.

Read more about the CMakePresets integration in the Conan documentation.

New MesonDeps generator

In most cases, when creating packages that use Meson as the build system, you use the MesonToolchain along with the PkgConfigDeps generator and then Meson will find the requirements using pkg-config. There are some cases, like the example below, where the build script uses the find_library() method directly:

project('mesonpackage', 'cpp')
cxx = meson.get_compiler('cpp')
mylib = cxx.find_library('mylib', required: true)
executable('app', 'main.cpp', dependencies: mylib)

In this case, Meson won’t use already known detection mechanisms like pkg-config, cmake or config-tool and you must inject the correct flags to the compiler to find those libraries. This is the use case of MesonDeps that will define the appropiate args and link_args variables to link with those libraries.

Ease Conan 2.0 migration

The migration process to Conan 2.0 compatible recipes has started in Conan Center Index and the Conan team is making a great effort to help in the migration process to Conan 2.0 compatible recipes. With that in mind, we have released several patch Conan versions up to Conan 1.51.3 and backported a few fixes to Conan 1.50.2 which is the Conan version used in Conan Center Index by this date. If you want to get ready for Conan 2.0, please do not forget to check the Conan migration guide to 2.0 in the Conan documentation.

Besides the items listed above, there were some minor bug fixes you may wish to read about. If so please refer to the changelog for the complete list.

We hope you enjoy this release and look forward to your feedback.