Stop extensions' servers and message loops before removing their files (#34208)

Fixes an issue that caused Windows to fail when removing extension's
directories, as Zed had never stop any related processes.

Now:

* Zed shuts down and waits until the end when the language servers are
shut down

* Adds `impl Drop for WasmExtension` where does
`self.tx.close_channel();` to stop a receiver loop that holds the "lock"
on the extension's work dir.
The extension was dropped, but the channel was not closed for some
reason.

* Does more unregistration to ensure `Arc<WasmExtension>` with the `tx`
does not leak further

* Tidies up the related errors which had never reported a problematic
path before

Release Notes:

- N/A

---------

Co-authored-by: Smit Barmase <heysmitbarmase@gmail.com>
Co-authored-by: Smit <smit@zed.dev>

crates/language_extension/Cargo.toml

@@ -21,6 +21,7 @@ fs.workspace = true
 gpui.workspace = true
 language.workspace = true
 lsp.workspace = true
+project.workspace = true
 serde.workspace = true
 serde_json.workspace = true
 util.workspace = true

crates/language_extension/src/extension_lsp_adapter.rs

@@ -6,21 +6,24 @@ use std::sync::Arc;
 
 use anyhow::{Context as _, Result};
 use async_trait::async_trait;
-use collections::HashMap;
+use collections::{HashMap, HashSet};
 use extension::{Extension, ExtensionLanguageServerProxy, WorktreeDelegate};
 use fs::Fs;
-use futures::{Future, FutureExt};
-use gpui::AsyncApp;
+use futures::{Future, FutureExt, future::join_all};
+use gpui::{App, AppContext, AsyncApp, Task};
 use language::{
     BinaryStatus, CodeLabel, HighlightId, Language, LanguageName, LanguageToolchainStore,
     LspAdapter, LspAdapterDelegate,
 };
-use lsp::{CodeActionKind, LanguageServerBinary, LanguageServerBinaryOptions, LanguageServerName};
+use lsp::{
+    CodeActionKind, LanguageServerBinary, LanguageServerBinaryOptions, LanguageServerName,
+    LanguageServerSelector,
+};
 use serde::Serialize;
 use serde_json::Value;
 use util::{ResultExt, fs::make_file_executable, maybe};
 
-use crate::LanguageServerRegistryProxy;
+use crate::{LanguageServerRegistryProxy, LspAccess};
 
 /// An adapter that allows an [`LspAdapterDelegate`] to be used as a [`WorktreeDelegate`].
 struct WorktreeDelegateAdapter(pub Arc<dyn LspAdapterDelegate>);
@@ -71,10 +74,50 @@ impl ExtensionLanguageServerProxy for LanguageServerRegistryProxy {
     fn remove_language_server(
         &self,
         language: &LanguageName,
-        language_server_id: &LanguageServerName,
-    ) {
+        language_server_name: &LanguageServerName,
+        cx: &mut App,
+    ) -> Task<Result<()>> {
         self.language_registry
-            .remove_lsp_adapter(language, language_server_id);
+            .remove_lsp_adapter(language, language_server_name);
+
+        let mut tasks = Vec::new();
+        match &self.lsp_access {
+            LspAccess::ViaLspStore(lsp_store) => lsp_store.update(cx, |lsp_store, cx| {
+                let stop_task = lsp_store.stop_language_servers_for_buffers(
+                    Vec::new(),
+                    HashSet::from_iter([LanguageServerSelector::Name(
+                        language_server_name.clone(),
+                    )]),
+                    cx,
+                );
+                tasks.push(stop_task);
+            }),
+            LspAccess::ViaWorkspaces(lsp_store_provider) => {
+                if let Ok(lsp_stores) = lsp_store_provider(cx) {
+                    for lsp_store in lsp_stores {
+                        lsp_store.update(cx, |lsp_store, cx| {
+                            let stop_task = lsp_store.stop_language_servers_for_buffers(
+                                Vec::new(),
+                                HashSet::from_iter([LanguageServerSelector::Name(
+                                    language_server_name.clone(),
+                                )]),
+                                cx,
+                            );
+                            tasks.push(stop_task);
+                        });
+                    }
+                }
+            }
+            LspAccess::Noop => {}
+        }
+
+        cx.background_spawn(async move {
+            let results = join_all(tasks).await;
+            for result in results {
+                result?;
+            }
+            Ok(())
+        })
     }
 
     fn update_language_server_status(

crates/language_extension/src/language_extension.rs

@@ -5,13 +5,26 @@ use std::sync::Arc;
 
 use anyhow::Result;
 use extension::{ExtensionGrammarProxy, ExtensionHostProxy, ExtensionLanguageProxy};
+use gpui::{App, Entity};
 use language::{LanguageMatcher, LanguageName, LanguageRegistry, LoadedLanguage};
+use project::LspStore;
+
+#[derive(Clone)]
+pub enum LspAccess {
+    ViaLspStore(Entity<LspStore>),
+    ViaWorkspaces(Arc<dyn Fn(&mut App) -> Result<Vec<Entity<LspStore>>> + Send + Sync + 'static>),
+    Noop,
+}
 
 pub fn init(
+    lsp_access: LspAccess,
     extension_host_proxy: Arc<ExtensionHostProxy>,
     language_registry: Arc<LanguageRegistry>,
 ) {
-    let language_server_registry_proxy = LanguageServerRegistryProxy { language_registry };
+    let language_server_registry_proxy = LanguageServerRegistryProxy {
+        language_registry,
+        lsp_access,
+    };
     extension_host_proxy.register_grammar_proxy(language_server_registry_proxy.clone());
     extension_host_proxy.register_language_proxy(language_server_registry_proxy.clone());
     extension_host_proxy.register_language_server_proxy(language_server_registry_proxy);
@@ -20,6 +33,7 @@ pub fn init(
 #[derive(Clone)]
 struct LanguageServerRegistryProxy {
     language_registry: Arc<LanguageRegistry>,
+    lsp_access: LspAccess,
 }
 
 impl ExtensionGrammarProxy for LanguageServerRegistryProxy {