allow passing compiler version via cmdline arg, to try using a really…

… old compiler that still supports save-analysis

src/analysis.rs

@@ -14,7 +14,7 @@ pub struct Analysis {
 }
 
 impl Analysis {
-    pub fn generate(workspace_path: impl AsRef<Path>) -> Result<(), String> {
+    pub fn generate(workspace_path: impl AsRef<Path>, compiler: &str) -> Result<(), String> {
         let config_json = serde_json::to_string(
             &rls_data::config::Config {
                 output_file: None, // use default paths
@@ -28,7 +28,7 @@ impl Analysis {
             .expect("failed to json-serialize rust analysis configuration");
 
         let cargo_status = Command::new("cargo")
-            .arg("+nightly")
+            .arg(format!("+{compiler}"))
             .arg("check")
             .arg("--target-dir")
             .arg(Path::new("target").join(SUBDIR))

src/main.rs

@@ -6,18 +6,37 @@ use rsbrowse::ui;
 
 struct Arguments {
     workspace_path: PathBuf,
+    compiler: String,
 }
 
 fn usage() {
     eprintln!("usage: {} <cargo workspace path>", std::env::args().next().unwrap());
 }
 
 fn parse_args() -> Option<Arguments> {
-    let workspace_path: PathBuf = std::env::args_os()
-        .nth(1)?
-        .into();
+    let mut args = std::env::args_os().skip(1);
+    let mut path = None;
+    let mut compiler = "nightly".to_owned();
+    loop {
+        let arg = match args.next() {
+            Some(a) => a,
+            None => break,
+        };
+        match arg.to_str() {
+            Some("--compiler") => {
+                compiler = args.next()?.to_string_lossy().into_owned();
+            }
+            _ => {
+                if path.is_some() {
+                    return None;
+                }
+                path = Some(arg);
+            }
+        }
+    }
     Some(Arguments {
-        workspace_path,
+        workspace_path: path?.into(),
+        compiler,
     })
 }
 
@@ -29,7 +48,7 @@ fn main() {
         });
 
     eprintln!("Running Cargo to generate analysis data...");
-    Analysis::generate(&args.workspace_path).unwrap();
+    Analysis::generate(&args.workspace_path, &args.compiler).unwrap();
 
     eprintln!("Reading analysis data...");
     let analysis = Analysis::load(&args.workspace_path);