Managing Meson projects (applicable to other build systems)

Step 1. Create a Meson build directory and get the compilation database

Suppose we have a simple Meson project consisting of a main.c file and the corresponding meson.build script, both located in the meson_test directory.

1. Create a build directory for the project:

   cd meson_test meson setup builddir

2. Meson automatically generates compile_command.json in builddir.

   If you need to create it manually, run the following ninja command:

   cd builddir ninja -t compdb c_COMPILER cpp_COMPILER > compile_commands.json

Step 2. Open and configure the compilation database in CLion

1. In CLion, go to File | Open and select the compile_command.json file created in step 1. Select Open as Project when prompted.

2. By default, CLion sets the directory containing compile_command.json as project root. Go to Tools | Compilation Database | Change Project Root and change it to the top-level meson_test directory.

Step 3. Install the File Watchers plugin

• Go to Settings | Plugins, switch to Marketplace, search for File Watchers, and install the plugin:

  

Step 4. Register meson.build as a recognizable file type

1. Go to Settings | Editor | File Types.

2. In the Recognized File Types section, click and specify the file type name (for example, Meson).

3. Select Meson in Recognized File Types, then click in the File name patterns field. Set the file pattern (meson.build in our case):

   

Step 5. Create a File Watcher for meson.build

Now we can create a File Watcher to follow up the changes in meson.build.

1. Go to Settings | Tools | File Watchers and add () a new custom watcher.

2. Configure the following settings:

   • In the File to Watch section, assign the watcher to Meson (the file type we created in step 4).

   • Set the Scope to Project files.

   • The Tool to Run on Changes section controls the program to be when the watcher is triggered. In our case, its ninja with the reconfigure argument, which will re-generate the compilation database.

     Also, we need to change the Working directory the builddir.

   

Step 6. Modify meson.build

1. As an example of how we can change the build script, let's add a new file (New | C/C++ Source File in the context menu of the Project view) and call it calc.c. Then we can add this file in meson.build:

   

2. Right after that change in meson.build, the file watcher is triggered to run ninja reconfigure. This command will regenerate the compilation database, and CLion will automatically reload it so the project gets synchronized with the modified build script.

3. We can check that now there are two entries in compile_commands.json:

   

Step 7. Make the File Watcher global

• The final thing that we might want to do is make the Meson_watcher global. With this setting enabled, the watcher becomes available across all projects so you will be able to easily reuse it for other Meson applications in CLion: