Merge branch 'example/fetch' into 'master'

feat: new example

See merge request CLIUtils/modern-cmake!40

chapters/projects/fetch.md

@@ -14,7 +14,7 @@ For example, to download Catch2:
 FetchContent_Declare(
   catch
   GIT_REPOSITORY https://github.com/catchorg/Catch2.git
-  GIT_TAG        v2.9.1
+  GIT_TAG        v2.13.0
 )
 
 # CMake 3.14+
@@ -48,4 +48,6 @@ endif()
 
 Now you have the CMake 3.14+ syntax in CMake 3.11+.
 
+See the example [here](https://gitlab.com/CLIUtils/modern-cmake/-/tree/master/examples/fetch).
+
 [FetchContent]: https://cmake.org/cmake/help/latest/module/FetchContent.html

examples/CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.11...3.16)
+cmake_minimum_required(VERSION 3.11...3.18)
 
 project(ModernCMakeExamples)
 set(MODERN_CMAKE_BUILD_TESTING ON)
@@ -7,6 +7,7 @@ include(CTest)
 
 add_subdirectory(simple-project)
 add_subdirectory(extended-project)
+add_subdirectory(fetch)
 
 add_subdirectory(root-usefile)
 add_subdirectory(root-simple)

examples/extended-project/tests/CMakeLists.txt

@@ -1,9 +1,9 @@
 # Testing library
 FetchContent_Declare(
-  catch2
+  catch
   GIT_REPOSITORY https://github.com/catchorg/Catch2.git
   GIT_TAG v2.9.1)
-FetchContent_MakeAvailable(catch2)
+FetchContent_MakeAvailable(catch)
 # Adds Catch2::Catch2
 
 # Tests need to be added as executables first

examples/fetch/CMakeLists.txt

@@ -0,0 +1,19 @@
+cmake_minimum_required(VERSION 3.14...3.18)
+
+project(FetchExample LANGUAGES CXX)
+
+include(FetchContent)
+include(CTest)
+
+FetchContent_Declare(
+  catch
+  GIT_REPOSITORY https://github.com/catchorg/Catch2.git
+  GIT_TAG        v2.13.0
+)
+
+# CMake 3.14+
+FetchContent_MakeAvailable(catch)
+
+add_executable(fetch_example main.cpp)
+target_link_libraries(fetch_example PRIVATE Catch2::Catch2)
+add_test(NAME fetch_example COMMAND fetch_example)

examples/fetch/main.cpp

@@ -0,0 +1,13 @@
+#define CATCH_CONFIG_MAIN  // This tells Catch to provide a main() - only do this in one cpp file
+#include "catch2/catch.hpp"
+
+unsigned int Factorial( unsigned int number ) {
+    return number <= 1 ? number : Factorial(number-1)*number;
+}
+
+TEST_CASE( "Factorials are computed", "[factorial]" ) {
+    REQUIRE( Factorial(1) == 1 );
+    REQUIRE( Factorial(2) == 2 );
+    REQUIRE( Factorial(3) == 6 );
+    REQUIRE( Factorial(10) == 3628800 );
+}