LS: Get rid of needless scarb metadata calls (#6689)

crates/cairo-lang-language-server/src/lang/db/swapper.rs

@@ -1,5 +1,6 @@
 use std::collections::HashSet;
 use std::panic::{AssertUnwindSafe, catch_unwind};
+use std::path::PathBuf;
 use std::sync::Arc;
 use std::time::{Duration, SystemTime};
 
@@ -56,6 +57,7 @@ impl AnalysisDatabaseSwapper {
         config: &Config,
         tricks: &Tricks,
         notifier: &Notifier,
+        loaded_scarb_manifests: &mut HashSet<PathBuf>,
     ) {
         let Ok(elapsed) = self.last_replace.elapsed() else {
             warn!("system time went backwards, skipping db swap");
@@ -71,7 +73,7 @@ impl AnalysisDatabaseSwapper {
             return;
         }
 
-        self.swap(db, open_files, config, tricks, notifier)
+        self.swap(db, open_files, config, tricks, notifier, loaded_scarb_manifests)
     }
 
     /// Swaps the database.
@@ -83,11 +85,20 @@ impl AnalysisDatabaseSwapper {
         config: &Config,
         tricks: &Tricks,
         notifier: &Notifier,
+        loaded_scarb_manifests: &mut HashSet<PathBuf>,
     ) {
         let Ok(new_db) = catch_unwind(AssertUnwindSafe(|| {
+            loaded_scarb_manifests.clear();
+
             let mut new_db = AnalysisDatabase::new(tricks);
             self.migrate_file_overrides(&mut new_db, db, open_files);
-            self.detect_crates_for_open_files(&mut new_db, open_files, config, notifier);
+            self.detect_crates_for_open_files(
+                &mut new_db,
+                open_files,
+                config,
+                notifier,
+                loaded_scarb_manifests,
+            );
             new_db
         })) else {
             error!("caught panic when preparing new db for swap");
@@ -130,14 +141,22 @@ impl AnalysisDatabaseSwapper {
         open_files: &HashSet<Url>,
         config: &Config,
         notifier: &Notifier,
+        loaded_scarb_manifests: &mut HashSet<PathBuf>,
     ) {
         for uri in open_files {
             let Ok(file_path) = uri.to_file_path() else {
                 // We are only interested in physical files.
                 continue;
             };
 
-            Backend::detect_crate_for(new_db, &self.scarb_toolchain, config, &file_path, notifier);
+            Backend::detect_crate_for(
+                new_db,
+                &self.scarb_toolchain,
+                config,
+                &file_path,
+                notifier,
+                loaded_scarb_manifests,
+            );
         }
     }
 }

crates/cairo-lang-language-server/src/lib.rs

@@ -38,6 +38,7 @@
 //! }
 //! ```
 
+use std::collections::HashSet;
 use std::panic::RefUnwindSafe;
 use std::path::{Path, PathBuf};
 use std::process::ExitCode;
@@ -55,7 +56,7 @@ use crossbeam::select;
 use lsp_server::Message;
 use lsp_types::RegistrationParams;
 use salsa::{Database, Durability};
-use tracing::{debug, error, info, warn};
+use tracing::{debug, error, info, trace, warn};
 
 use crate::config::Config;
 use crate::lang::db::AnalysisDatabase;
@@ -66,7 +67,7 @@ use crate::lsp::capabilities::server::{
 use crate::lsp::ext::{CorelibVersionMismatch, ScarbMetadataFailed};
 use crate::lsp::result::LSPResult;
 use crate::project::ProjectManifestPath;
-use crate::project::scarb::update_crate_roots;
+use crate::project::scarb::{get_workspace_members_manifests, update_crate_roots};
 use crate::project::unmanaged_core_crate::try_to_init_unmanaged_core;
 use crate::server::client::{Notifier, Requester, Responder};
 use crate::server::connection::{Connection, ConnectionInitializer};
@@ -377,6 +378,7 @@ impl Backend {
             &state.config,
             &state.tricks,
             &notifier,
+            &mut state.loaded_scarb_manifests,
         );
     }
 
@@ -394,9 +396,15 @@ impl Backend {
         config: &Config,
         file_path: &Path,
         notifier: &Notifier,
+        loaded_scarb_manifests: &mut HashSet<PathBuf>,
     ) {
         match ProjectManifestPath::discover(file_path) {
             Some(ProjectManifestPath::Scarb(manifest_path)) => {
+                if loaded_scarb_manifests.contains(&manifest_path) {
+                    trace!("scarb project is already loaded: {}", manifest_path.display());
+                    return;
+                }
+
                 let metadata = scarb_toolchain
                     .metadata(&manifest_path)
                     .with_context(|| {
@@ -409,6 +417,7 @@ impl Backend {
                     .ok();
 
                 if let Some(metadata) = metadata {
+                    loaded_scarb_manifests.extend(get_workspace_members_manifests(&metadata));
                     update_crate_roots(&metadata, db);
                 } else {
                     // Try to set up a corelib at least.
@@ -449,6 +458,7 @@ impl Backend {
         notifier: &Notifier,
         requester: &mut Requester<'_>,
     ) -> LSPResult<()> {
+        state.loaded_scarb_manifests.clear();
         state.config.reload(requester, &state.client_capabilities)?;
 
         for uri in state.open_files.iter() {
@@ -460,6 +470,7 @@ impl Backend {
                     &state.config,
                     &file_path,
                     notifier,
+                    &mut state.loaded_scarb_manifests,
                 );
             }
         }

crates/cairo-lang-language-server/src/project/scarb.rs

@@ -1,6 +1,6 @@
 use std::collections::HashMap;
 use std::fs;
-use std::path::Path;
+use std::path::{Path, PathBuf};
 
 use anyhow::{Context, Result, bail, ensure};
 use cairo_lang_filesystem::cfg::CfgSet;
@@ -18,6 +18,16 @@ use tracing::{debug, error, warn};
 use crate::lang::db::AnalysisDatabase;
 use crate::project::crate_data::Crate;
 
+/// Get paths to manifests of the workspace members.
+pub fn get_workspace_members_manifests(metadata: &Metadata) -> Vec<PathBuf> {
+    metadata
+        .workspace
+        .members
+        .iter()
+        .map(|package_id| metadata[package_id].manifest_path.clone().into())
+        .collect()
+}
+
 /// Updates crate roots in the database with the information from Scarb metadata.
 ///
 /// This function attempts to be graceful. Any erroneous cases will be reported as warnings in logs,

crates/cairo-lang-language-server/src/server/routing/traits.rs

@@ -250,6 +250,7 @@ impl SyncNotificationHandler for DidOpenTextDocument {
                 &state.config,
                 &path,
                 &notifier,
+                &mut state.loaded_scarb_manifests,
             );
         }
 

crates/cairo-lang-language-server/src/state.rs

@@ -1,5 +1,6 @@
 use std::collections::HashSet;
 use std::ops::{Deref, DerefMut};
+use std::path::PathBuf;
 use std::sync::Arc;
 
 use lsp_types::{ClientCapabilities, Url};
@@ -17,6 +18,7 @@ use crate::toolchain::scarb::ScarbToolchain;
 pub struct State {
     pub db: AnalysisDatabase,
     pub open_files: Owned<HashSet<Url>>,
+    pub loaded_scarb_manifests: Owned<HashSet<PathBuf>>,
     pub config: Owned<Config>,
     pub client_capabilities: Owned<ClientCapabilities>,
     pub scarb_toolchain: ScarbToolchain,
@@ -38,6 +40,7 @@ impl State {
         Self {
             db: AnalysisDatabase::new(&tricks),
             open_files: Default::default(),
+            loaded_scarb_manifests: Default::default(),
             config: Default::default(),
             client_capabilities: Owned::new(client_capabilities.into()),
             scarb_toolchain,