fix: Notify user that linkedProjects is set when failing to discover projects

crates/rust-analyzer/src/config.rs

@@ -7,7 +7,11 @@
 //! configure the server itself, feature flags are passed into analysis, and
 //! tweak things like automatic insertion of `()` in completions.
 
-use std::{fmt, iter, ops::Not, path::PathBuf};
+use std::{
+    fmt, iter,
+    ops::Not,
+    path::{Path, PathBuf},
+};
 
 use cfg::{CfgAtom, CfgDiff};
 use flycheck::FlycheckConfig;
@@ -917,7 +921,19 @@ impl Config {
     pub fn has_linked_projects(&self) -> bool {
         !self.data.linkedProjects.is_empty()
     }
-    pub fn linked_projects(&self) -> Vec<LinkedProject> {
+    pub fn linked_manifests(&self) -> impl Iterator<Item = &Path> + '_ {
+        self.data.linkedProjects.iter().filter_map(|it| match it {
+            ManifestOrProjectJson::Manifest(p) => Some(&**p),
+            ManifestOrProjectJson::ProjectJson(_) => None,
+        })
+    }
+    pub fn has_linked_project_jsons(&self) -> bool {
+        self.data
+            .linkedProjects
+            .iter()
+            .any(|it| matches!(it, ManifestOrProjectJson::ProjectJson(_)))
+    }
+    pub fn linked_or_discovered_projects(&self) -> Vec<LinkedProject> {
         match self.data.linkedProjects.as_slice() {
             [] => {
                 let exclude_dirs: Vec<_> =
@@ -952,15 +968,6 @@ impl Config {
         }
     }
 
-    pub fn add_linked_projects(&mut self, linked_projects: Vec<ProjectJsonData>) {
-        let mut linked_projects = linked_projects
-            .into_iter()
-            .map(ManifestOrProjectJson::ProjectJson)
-            .collect::<Vec<ManifestOrProjectJson>>();
-
-        self.data.linkedProjects.append(&mut linked_projects);
-    }
-
     pub fn did_save_text_document_dynamic_registration(&self) -> bool {
         let caps = try_or_def!(self.caps.text_document.as_ref()?.synchronization.clone()?);
         caps.did_save == Some(true) && caps.dynamic_registration == Some(true)

crates/rust-analyzer/src/handlers/request.rs

@@ -801,7 +801,7 @@ pub(crate) fn handle_runnables(
             }
         }
         None => {
-            if !snap.config.linked_projects().is_empty() {
+            if !snap.config.linked_or_discovered_projects().is_empty() {
                 res.push(lsp_ext::Runnable {
                     label: "cargo check --workspace".to_string(),
                     location: None,

crates/rust-analyzer/src/reload.rs

@@ -80,7 +80,8 @@ impl GlobalState {
                 &self.config.lru_query_capacities().cloned().unwrap_or_default(),
             );
         }
-        if self.config.linked_projects() != old_config.linked_projects() {
+        if self.config.linked_or_discovered_projects() != old_config.linked_or_discovered_projects()
+        {
             self.fetch_workspaces_queue.request_op("linked projects changed".to_string(), false)
         } else if self.config.flycheck() != old_config.flycheck() {
             self.reload_flycheck();
@@ -128,7 +129,7 @@ impl GlobalState {
             status.health = lsp_ext::Health::Warning;
             message.push_str("Auto-reloading is disabled and the workspace has changed, a manual workspace reload is required.\n\n");
         }
-        if self.config.linked_projects().is_empty()
+        if self.config.linked_or_discovered_projects().is_empty()
             && self.config.detached_files().is_empty()
             && self.config.notifications().cargo_toml_not_found
         {
@@ -174,7 +175,21 @@ impl GlobalState {
 
         if let Err(_) = self.fetch_workspace_error() {
             status.health = lsp_ext::Health::Error;
-            message.push_str("Failed to load workspaces.\n\n");
+            message.push_str("Failed to load workspaces.");
+
+            if self.config.has_linked_projects() {
+                message.push_str(
+                    "`rust-analyzer.linkedProjects` have been specified, which may be incorrect. Specified project paths:\n",
+                );
+                message.push_str(&format!(
+                    "    {}",
+                    self.config.linked_manifests().map(|it| it.display()).format("\n    ")
+                ));
+                if self.config.has_linked_project_jsons() {
+                    message.push_str("\nAdditionally, one or more project jsons are specified")
+                }
+            }
+            message.push_str("\n\n");
         }
 
         if !message.is_empty() {
@@ -187,7 +202,7 @@ impl GlobalState {
         tracing::info!(%cause, "will fetch workspaces");
 
         self.task_pool.handle.spawn_with_sender(ThreadIntent::Worker, {
-            let linked_projects = self.config.linked_projects();
+            let linked_projects = self.config.linked_or_discovered_projects();
             let detached_files = self.config.detached_files().to_vec();
             let cargo_config = self.config.cargo();