exit after writing compile_commands

src/main.rs

@@ -2,6 +2,7 @@ use clap::Parser;
 use std::{
     fs::{read_to_string, write},
     path::Path,
+    process::exit,
 };
 use toml::{Table, Value};
 
@@ -179,6 +180,8 @@ fn main() {
             &gen_compile_commands(&target_for_comp_cmds, &config.build_dir),
         )
         .unwrap_or_else(|e| panic!("fatal: could not write {file}: {e}"));
+        // no need to write ninja file
+        exit(0);
     }
 
     let build_dir = &config.build_dir;