Propagate exit code from Dart command

documentation/docs/running-and-building.md

@@ -29,8 +29,8 @@ To serve[^3] the web application:
 [^3]: Note that Flutter apps in debug mode are known to be quite slow on the web. It is recommended to use release mode when testing on a web browser. Debug mode can be used if you need to analyze the code more deeply, without the `--release` argument.
 
 ```bash title="CLI"
-rinf wasm --release
-flutter run --release  # Choose a browser
+rinf wasm
+flutter run --web-header=Cross-Origin-Opener-Policy=same-origin --web-header=Cross-Origin-Embedder-Policy=require-corp
 ```
 
 To build the optimized release version of the web application[^4]:
@@ -42,6 +42,12 @@ rinf wasm --release
 flutter build web
 ```
 
+Since repeatedly writing web header arguments during development can be overwhelming, Rinf provides a convenient command that prints the full Flutter web command.
+
+```bash title="CLI"
+rinf server
+```
+
 When deploying your web app on a web server, ensure that your web server is configured to include cross-origin-related HTTP headers in its responses. These headers enable web browsers using your website to gain access to `SharedArrayBuffer` web API, which is something similar to shared memory on the web.
 
 - [`Cross-Origin-Opener-Policy`](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cross-Origin-Opener-Policy): `same-origin`

flutter_package/bin/rinf.dart

@@ -1,3 +1,5 @@
+import 'dart:io';
+
 import 'package:args/command_runner.dart';
 import 'package:chalkdart/chalkstrings.dart';
 
@@ -10,7 +12,7 @@ import 'src/common.dart';
 Future<void> main(List<String> args) async {
   // When running `dart run rinf`,
   // Unnecessary two lines of
-  //`Building package executable...\nBuilt rinf:rinf.` appear.
+  // `Building package executable...\nBuilt rinf:rinf.` appear.
   // Remove those before proceeding.
   removeCliLines(2);
 
@@ -34,6 +36,8 @@ Future<void> main(List<String> args) async {
   } catch (error) {
     // Print the error gracefully without backtrace.
     print(error.toString().trim().red);
+    // Exit code 1 is assigned to Rust-side wrapper executable.
+    exit(2);
   }
 }
 

rust_crate/src/main.rs

@@ -8,51 +8,47 @@ fn main() -> Result<(), String> {
     // Ensure Protobuf compiler.
     let protoc_path = if let Ok(installed) = which::which("protoc") {
         // Get the path of Protobuf compiler that's already installed.
-        println!("Detected `protoc`, skipping auto installation.");
+        println!("Detected `protoc`, skipping auto installation");
         installed
             .parent()
-            .ok_or("Could not get the parent of `protoc` path.")?
+            .ok_or("Could not get the parent of `protoc` path")?
             .to_path_buf()
     } else {
         // Install Protobuf compiler and get the path.
         let home_path = home::home_dir()
-            .ok_or("Could not get home directory for `protoc` installation.")?;
+            .ok_or("Could not get home directory for `protoc` installation")?;
         let out_path = home_path.join(".local").join("bin");
         fs::create_dir_all(&out_path).map_err(|_| {
-            "Could not create the folder for `protoc` installation."
+            "Could not create the folder for `protoc` installation"
         })?;
         env::set_var(
             "OUT_DIR",
             out_path
                 .to_str()
-                .ok_or("Could not set the path for `protoc` installation.")?,
+                .ok_or("Could not set the path for `protoc` installation")?,
         );
         let install_result = protoc_prebuilt::init("25.2");
-        let (protoc_binary_path, _) = install_result.map_err(|_| {
-            format!(
-                "{}\n{}",
-                "Automatic installation of `protoc` failed.",
-                "Try installing `protoc` manually and adding it to PATH."
-            )
-        })?;
+        let (protoc_binary_path, _) = install_result.map_err(|_|
+            "Automatic installation of `protoc` failed, try installing it manually"
+        )?;
         protoc_binary_path
             .parent()
-            .ok_or("Could not get the parent of installed `protoc` path.")?
+            .ok_or("Could not get the parent of newly-installed `protoc` path")?
             .to_path_buf()
     };
 
     // Find the path where Dart executables are located.
     #[cfg(target_family = "windows")]
     let pub_cache_bin_path = path::PathBuf::from(
         env::var("LOCALAPPDATA")
-            .map_err(|_| "Could not get `LOCALAPPDATA` path.")?,
+            .map_err(|_| "Could not get `LOCALAPPDATA` path")?,
     )
     .join("Pub")
     .join("Cache")
     .join("bin");
     #[cfg(target_family = "unix")]
     let pub_cache_bin_path = path::PathBuf::from(
-        env::var("HOME").map_err(|_| "Could get find `HOME` path.")?,
+        env::var("HOME").map_err(|_| "Could get find `HOME` path")?,
     )
     .join(".pub-cache")
     .join("bin");
@@ -67,19 +63,26 @@ fn main() -> Result<(), String> {
     env::set_var(
         "PATH",
         env::join_paths(path_var)
-            .map_err(|_| "Could not push required values to `PATH`.")?,
+            .map_err(|_| "Could not push required values to `PATH`")?,
     );
 
     // Get command-line arguments excluding the program name.
     let dart_command_args: Vec<String> = env::args().skip(1).collect();
 
     // Run the Dart script.
     let dart_path = which::which("dart")
-        .map_err(|_| "Could not find where Dart is located.")?;
+        .map_err(|_| "Could not find where Dart is located")?;
     let mut command = process::Command::new(dart_path);
     command.args(["run", "rinf"]);
     command.args(&dart_command_args);
-    command.status().map_err(|_| "Rinf command has failed.")?;
+    let exit_status =
+        command.status().map_err(|_| "Could not run Rinf command")?;
+    let exit_code = exit_status
+        .code()
+        .ok_or("Could not get Rinf command exit code")?;
+    if exit_code != 0 {
+        process::exit(exit_code);
+    }
 
     Ok(())
 }