To run CTest with coverage by Visual Studio 2019 from the command line, you can use the `ctest` command and specify code coverage options. Here are the steps to achieve this:
1. **Generate Code Coverage Data**:
Before running CTest with coverage, you need to ensure that your CMake configuration generates code coverage data. You can do this by adding the following lines to your `CMakeLists.txt`:
```cmake
set(CMAKE_CXX_FLAGS "--coverage")
set(CMAKE_C_FLAGS "--coverage")
set(CMAKE_EXE_LINKER_FLAGS "--coverage")
```
These flags will enable code coverage instrumentation.
2. **Build Your Project**:
Make sure you build your project with these new CMake settings. You can use `cmake` to configure and `cmmake --build` to build your project:
```bash
cmake --build . --config Release
```
3. **Run Tests with CTest**:
After building, you can use CTest to run your tests:
```bash
ctest
```
Ensure that your tests include both unit tests and any additional tests you want to measure for code coverage.
4. **Collect Code Coverage Data**:
After running your tests with CTest, code coverage data will be collected. You can find the coverage data files in the `Testing/Temporary` directory.
5. **Generate Code Coverage Report**:
To generate a code coverage report, you can use the `lcov` tool. If it's not installed, you may need to install it on your system.
```bash
lcov --capture --directory . --output-file coverage.info
genhtml coverage.info --output-directory coverage-report
```
This will generate a code coverage report in the `coverage-report` directory.
6. **View the Code Coverage Report**:
You can now open the generated HTML report in a web browser to view the code coverage details:
```bash
open coverage-report/index.html
```
This process assumes that you have configured your project for CMake and Visual Studio, and you are using a compatible compiler with code coverage support. Note that Visual Studio 2019 does not have built-in support for code coverage reports, so you'll need to use external tools like `lcov` to generate and view the reports.