From 55bf9a9c1d5cba98e24457d0ba62e77f88852def Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Fri, 12 Jan 2024 14:20:27 +0100
Subject: [PATCH] feat: `use_fmtlib` Conan option added

---
 conanfile.py                                   | 15 +++++----------
 docs/getting_started/installation_and_usage.md | 13 +++++++++++--
 test_package/conanfile.py                      | 11 +++--------
 3 files changed, 19 insertions(+), 20 deletions(-)

diff --git a/conanfile.py b/conanfile.py
index b2a8938a..d5f1e0df 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -56,9 +56,11 @@ class MPUnitsConan(ConanFile):
     settings = "os", "arch", "compiler", "build_type"
     options = {
         "cxx_modules": [True, False],
+        "use_fmtlib": [True, False],
     }
     default_options = {
         "cxx_modules": False,
+        "use_fmtlib": True,
     }
     tool_requires = "cmake/[>=3.28.1]"
     exports = ["LICENSE.md"]
@@ -94,13 +96,6 @@ class MPUnitsConan(ConanFile):
     def _skip_la(self):
         return bool(self.conf.get("user.build:skip_la", default=False))
 
-    @property
-    def _use_libfmt(self):
-        compiler = self.settings.compiler
-        version = Version(self.settings.compiler.version)
-        std_support = compiler == "msvc" and version >= 193 and compiler.cppstd == 23
-        return not std_support
-
     def set_version(self):
         content = load(self, os.path.join(self.recipe_folder, "src/CMakeLists.txt"))
         version = re.search(
@@ -110,7 +105,7 @@ class MPUnitsConan(ConanFile):
 
     def requirements(self):
         self.requires("gsl-lite/0.41.0")
-        if self._use_libfmt:
+        if self.options.use_fmtlib:
             self.requires("fmt/10.2.1")
 
     def build_requirements(self):
@@ -146,7 +141,7 @@ class MPUnitsConan(ConanFile):
             tc.variables["CMAKE_CXX_SCAN_FOR_MODULES"] = True
             tc.variables["MP_UNITS_BUILD_CXX_MODULES"] = True
         tc.variables["MP_UNITS_BUILD_LA"] = self._build_all and not self._skip_la
-        tc.variables["MP_UNITS_USE_FMTLIB"] = self._use_libfmt
+        tc.variables["MP_UNITS_USE_FMTLIB"] = bool(self.options.use_fmtlib)
         tc.generate()
         deps = CMakeDeps(self)
         deps.generate()
@@ -176,7 +171,7 @@ class MPUnitsConan(ConanFile):
     def package_info(self):
         compiler = self.settings.compiler
         self.cpp_info.components["core"].requires = ["gsl-lite::gsl-lite"]
-        if self._use_libfmt:
+        if self.options.use_fmtlib:
             self.cpp_info.components["core"].requires.append("fmt::fmt")
         if compiler == "msvc":
             self.cpp_info.components["core"].cxxflags = ["/utf-8"]
diff --git a/docs/getting_started/installation_and_usage.md b/docs/getting_started/installation_and_usage.md
index c8c3730d..6e36413b 100644
--- a/docs/getting_started/installation_and_usage.md
+++ b/docs/getting_started/installation_and_usage.md
@@ -181,7 +181,16 @@ tools.build:compiler_executables={"c": "gcc-12", "cpp": "g++-12"}
 
     Configures CMake to add C++ modules to the list of default targets.
 
-[cxx modules support]: https://github.com/mpusz/mp-units/releases/tag/v2.2.0
+    [cxx modules support]: https://github.com/mpusz/mp-units/releases/tag/v2.2.0
+
+[use_fmtlib](#use_fmtlib){ #use_fmtlib }
+
+:   [:octicons-tag-24: 2.2.0][use fmtlib support] · :octicons-milestone-24: `True`/`False` (Default: `True`)
+
+    Forces usage of [{fmt}](https://github.com/fmtlib/fmt) library instead of the C++20 Standard
+    Library features.
+
+    [use fmtlib support]: https://github.com/mpusz/mp-units/releases/tag/v2.2.0
 
 ### Conan configuration properties
 
@@ -195,7 +204,7 @@ tools.build:compiler_executables={"c": "gcc-12", "cpp": "g++-12"}
     [`tools.build:skip_test`](https://docs.conan.io/2/reference/commands/config.html?highlight=tools.build:skip_test#conan-config-list)
     configuration property is set to `True`).
 
-[build all support]: https://github.com/mpusz/mp-units/releases/tag/v0.8.0
+    [build all support]: https://github.com/mpusz/mp-units/releases/tag/v0.8.0
 
 
 [`user.build:skip_la`](#user-skip-la){ #user-skip-la }
diff --git a/test_package/conanfile.py b/test_package/conanfile.py
index 0a870a02..4234d8cd 100644
--- a/test_package/conanfile.py
+++ b/test_package/conanfile.py
@@ -32,13 +32,6 @@ class TestPackageConan(ConanFile):
     settings = "os", "arch", "compiler", "build_type"
     generators = "CMakeDeps"
 
-    @property
-    def _use_libfmt(self):
-        compiler = self.settings.compiler
-        version = Version(self.settings.compiler.version)
-        std_support = compiler == "msvc" and version >= 193 and compiler.cppstd == 23
-        return not std_support
-
     def requirements(self):
         self.requires(self.tested_reference_str)
 
@@ -47,7 +40,9 @@ class TestPackageConan(ConanFile):
 
     def generate(self):
         tc = CMakeToolchain(self)
-        tc.variables["MP_UNITS_USE_FMTLIB"] = self._use_libfmt
+        tc.variables["MP_UNITS_USE_FMTLIB"] = bool(
+            self.dependencies["mp-units"].options.use_fmtlib
+        )
         tc.generate()
 
     def build(self):