fix: Remove uses of std::process::exit (#963)

* remove exit

* small change

* fix clippy

* review

* review

crates/nargo/src/cli/check_cmd.rs

@@ -32,9 +32,7 @@ fn check_from_path<P: AsRef<Path>>(p: P, compile_options: &CompileOptions) -> Re
     let mut driver = Resolver::resolve_root_config(p.as_ref(), backend.np_language())?;
     add_std_lib(&mut driver);
 
-    if driver.check_crate(compile_options).is_err() {
-        std::process::exit(1);
-    }
+    driver.check_crate(compile_options).map_err(|_| CliError::CompilationError)?;
 
     // XXX: We can have a --overwrite flag to determine if you want to overwrite the Prover/Verifier.toml files
     if let Some((parameters, return_type)) = driver.compute_function_signature() {

crates/nargo/src/cli/compile_cmd.rs

@@ -45,7 +45,7 @@ pub(crate) fn run(mut args: CompileCommand, config: NargoConfig) -> Result<(), C
         }
         Ok(())
     } else {
-        let main = driver.main_function();
+        let main = driver.main_function().map_err(|_| CliError::CompilationError)?;
         compile_and_save_program(&driver, main, &args, &circuit_dir)
     }
 }

crates/nargo/src/cli/test_cmd.rs

@@ -36,9 +36,7 @@ fn run_tests(
     let mut driver = Resolver::resolve_root_config(program_dir, backend.np_language())?;
     add_std_lib(&mut driver);
 
-    if driver.check_crate(compile_options).is_err() {
-        std::process::exit(1);
-    }
+    driver.check_crate(compile_options).map_err(|_| CliError::CompilationError)?;
 
     let test_functions = driver.get_all_test_functions_in_crate_matching(test_name);
     println!("Running {} test functions...", test_functions.len());
@@ -68,9 +66,7 @@ fn run_tests(
         writeln!(writer, "All tests passed").ok();
     } else {
         let plural = if failing == 1 { "" } else { "s" };
-        writer.set_color(ColorSpec::new().set_fg(Some(Color::Red))).unwrap();
-        writeln!(writer, "{failing} test{plural} failed").ok();
-        std::process::exit(1);
+        return Err(CliError::Generic(format!("{failing} test{plural} failed")));
     }
 
     writer.reset().ok();

crates/noirc_driver/src/lib.rs

@@ -53,10 +53,13 @@ impl Driver {
 
     // This is here for backwards compatibility
     // with the restricted version which only uses one file
-    pub fn compile_file(root_file: PathBuf, np_language: acvm::Language) -> CompiledProgram {
+    pub fn compile_file(
+        root_file: PathBuf,
+        np_language: acvm::Language,
+    ) -> Result<CompiledProgram, ReportedError> {
         let mut driver = Driver::new(&np_language);
         driver.create_local_crate(root_file, CrateType::Binary);
-        driver.compile_main(&CompileOptions::default()).unwrap_or_else(|_| std::process::exit(1))
+        driver.compile_main(&CompileOptions::default())
     }
 
     /// Compiles a file and returns true if compilation was successful
@@ -167,26 +170,35 @@ impl Driver {
         options: &CompileOptions,
     ) -> Result<CompiledProgram, ReportedError> {
         self.check_crate(options)?;
-        let main = self.main_function();
+        let main = match self.main_function() {
+            Ok(m) => m,
+            Err(e) => {
+                println!("cannot compile a program with no main function");
+                return Err(e);
+            }
+        };
         self.compile_no_check(options, main)
     }
 
     /// Returns the FuncId of the 'main' funciton.
     /// - Expects check_crate to be called beforehand
     /// - Panics if no main function is found
-    pub fn main_function(&self) -> FuncId {
+    pub fn main_function(&self) -> Result<FuncId, ReportedError> {
         // Find the local crate, one should always be present
         let local_crate = self.context.def_map(LOCAL_CRATE).unwrap();
 
         // Check the crate type
         // We don't panic here to allow users to `evaluate` libraries which will do nothing
         if self.context.crate_graph[LOCAL_CRATE].crate_type != CrateType::Binary {
             println!("cannot compile crate into a program as the local crate is not a binary. For libraries, please use the check command");
-            std::process::exit(1);
+            return Err(ReportedError);
         };
 
         // All Binaries should have a main function
-        local_crate.main_function().expect("cannot compile a program with no main function")
+        match local_crate.main_function() {
+            Some(func_id) => Ok(func_id),
+            None => Err(ReportedError),
+        }
     }
 
     /// Compile the current crate. Assumes self.check_crate is called beforehand!

crates/wasm/src/lib.rs

@@ -28,7 +28,10 @@ pub fn compile(src: String) -> JsValue {
     // For now we default to plonk width = 3, though we can add it as a parameter
     let language = acvm::Language::PLONKCSat { width: 3 };
     let path = PathBuf::from(src);
-    let compiled_program = noirc_driver::Driver::compile_file(path, language);
+    let compiled_program = match noirc_driver::Driver::compile_file(path, language) {
+        Ok(compiled_program) => compiled_program,
+        Err(_) => panic!("Compilation Error: Failed to compile circuit"),
+    };
     <JsValue as JsValueSerdeExt>::from_serde(&compiled_program).unwrap()
 }