feat: run rescript-legacy when passing --legacy

Author: Bushuo

src/build.rs

@@ -22,6 +22,7 @@ use std::fmt;
 use std::fs::File;
 use std::io::{stdout, Write};
 use std::path::PathBuf;
+use std::process::Stdio;
 use std::time::{Duration, Instant};
 
 use self::compile::compiler_args;
@@ -506,3 +507,18 @@ pub fn build(
         }
     }
 }
+
+pub fn pass_through_legacy(args: Vec<String>) -> i32 {
+    let project_root = helpers::get_abs_path(".");
+    let workspace_root = helpers::get_workspace_root(&project_root);
+
+    let bsb_path = helpers::get_rescript_legacy(&project_root, workspace_root);
+
+    let status = std::process::Command::new(bsb_path)
+        .args(args)
+        .stdout(Stdio::inherit())
+        .stderr(Stdio::inherit())
+        .status();
+
+    status.map(|s| s.code().unwrap_or(1)).unwrap_or(1)
+}

src/helpers.rs

@@ -146,6 +146,21 @@ pub fn create_build_path(build_path: &str) {
         .unwrap();
 }
 
+pub fn get_rescript_legacy(root_path: &str, workspace_root: Option<String>) -> String {
+    match (
+        PathBuf::from(format!("{}/node_modules/rescript/rescript", root_path)).canonicalize(),
+        workspace_root.map(|workspace_root| {
+            PathBuf::from(format!("{}/node_modules/rescript/rescript", workspace_root)).canonicalize()
+        }),
+    ) {
+        (Ok(path), _) => path,
+        (_, Some(Ok(path))) => path,
+        _ => panic!("Could not find rescript"),
+    }
+    .to_string_lossy()
+    .to_string()
+}
+
 pub fn get_bsc(root_path: &str, workspace_root: Option<String>) -> String {
     let subfolder = match (std::env::consts::OS, std::env::consts::ARCH) {
         ("macos", "aarch64") => "darwinarm64",

src/main.rs

@@ -89,18 +89,15 @@ struct Args {
     ///
     /// After this flag is encountered, the rest of the command line arguments are passed to the legacy build system.
     #[arg(long, allow_hyphen_values = true, num_args = 0..)]
-    legacy: Vec<String>,
+    legacy: Option<Vec<String>>,
 }
 
 fn main() -> Result<()> {
     let args = Args::parse();
 
-    if !args.legacy.is_empty() {
-        let s = std::env::args().collect::<Vec<String>>().join(" ");
-
-        println!("Using legacy build system");
-        println!("Running: {s}");
-        std::process::exit(0);
+    if let Some(legacy_args) = args.legacy {
+        let code = build::pass_through_legacy(legacy_args);
+        std::process::exit(code);
     }
 
     let log_level_filter = args.verbose.log_level_filter();