Support different toolchains per folder

src/commands.ts

@@ -46,7 +46,7 @@ import { runTask } from "./commands/runTask";
 import { TestKind } from "./TestExplorer/TestKind";
 import { pickProcess } from "./commands/pickProcess";
 import { openDocumentation } from "./commands/openDocumentation";
-import showFolderSelectionQuickPick from "./utilities/folderQuickPick";
+import restartLSPServer from "./commands/restartLSPServer";
 
 /**
  * References:
@@ -97,6 +97,7 @@ export enum Commands {
     DEBUG_ALL_TESTS = "swift.debugAllTests",
     COVER_ALL_TESTS = "swift.coverAllTests",
     OPEN_MANIFEST = "swift.openManifest",
+    RESTART_LSP = "swift.restartLSPServer",
 }
 
 /**
@@ -147,19 +148,7 @@ export function register(ctx: WorkspaceContext): vscode.Disposable[] {
         ),
         vscode.commands.registerCommand(Commands.RUN_PLUGIN_TASK, () => runPluginTask()),
         vscode.commands.registerCommand(Commands.RUN_TASK, name => runTask(ctx, name)),
-        vscode.commands.registerCommand("swift.restartLSPServer", async () => {
-            const folder =
-                ctx.currentFolder ??
-                (await showFolderSelectionQuickPick(
-                    ctx,
-                    "Select a folder to restart the LSP server for"
-                ));
-            if (!folder) {
-                return;
-            }
-            const languageClientManager = ctx.languageClientManager.get(folder);
-            await languageClientManager.restart();
-        }),
+        vscode.commands.registerCommand(Commands.RESTART_LSP, () => restartLSPServer(ctx)),
         vscode.commands.registerCommand("swift.reindexProject", () => reindexProject(ctx)),
         vscode.commands.registerCommand("swift.insertFunctionComment", () =>
             insertFunctionComment(ctx)

src/commands/dependencies/resolve.ts

@@ -17,15 +17,12 @@ import { FolderContext } from "../../FolderContext";
 import { createSwiftTask, SwiftTaskProvider } from "../../tasks/SwiftTaskProvider";
 import { WorkspaceContext } from "../../WorkspaceContext";
 import { executeTaskWithUI, updateAfterError } from "../utilities";
-import showFolderSelectionQuickPick from "../../utilities/folderQuickPick";
 
 /**
  * Executes a {@link vscode.Task task} to resolve this package's dependencies.
  */
 export async function resolveDependencies(ctx: WorkspaceContext) {
-    const current =
-        ctx.currentFolder ??
-        (await showFolderSelectionQuickPick(ctx, "Select a folder to resolve dependencies for"));
+    const current = ctx.currentFolder;
     if (!current) {
         return false;
     }

src/commands/restartLSPServer.ts

@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the VS Code Swift open source project
+//
+// Copyright (c) 2025 the VS Code Swift project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of VS Code Swift project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import * as vscode from "vscode";
+import { WorkspaceContext } from "../WorkspaceContext";
+import { FolderContext } from "../FolderContext";
+
+export default async function restartLSPServer(ctx: WorkspaceContext) {
+    const toolchainLookup = ctx.folders.reduce(
+        (acc, folder) => {
+            acc[folder.swiftVersion.toString()] = acc[folder.swiftVersion.toString()] ?? [];
+            acc[folder.swiftVersion.toString()].push({
+                folder,
+                fullToolchainName: folder.toolchain.swiftVersionString,
+            });
+            return acc;
+        },
+        {} as Record<string, { folder: FolderContext; fullToolchainName: string }[]>
+    );
+
+    const toolchains: vscode.QuickPickItem[] = Object.keys(toolchainLookup).map(key => ({
+        label: key,
+        description: toolchainLookup[key][0].fullToolchainName,
+        detail: toolchainLookup[key].map(({ folder }) => folder.name).join(", "),
+    }));
+
+    // Skip picking a toolchain if there is only one option to pick
+    if (toolchains.length === 1) {
+        return restartLSP(ctx, toolchains[0].label);
+    }
+
+    const selected = await vscode.window.showQuickPick(toolchains, {
+        title: "Restart LSP server",
+        placeHolder: "Select a sourcekit-lsp instance to restart",
+        canPickMany: false,
+    });
+
+    if (!selected) {
+        return undefined;
+    }
+
+    return restartLSP(ctx, selected.label);
+}
+
+async function restartLSP(ctx: WorkspaceContext, version: string) {
+    const languageClientManager = ctx.languageClientManager.getByVersion(version);
+    await languageClientManager.restart();
+}

src/sourcekit-lsp/LanguageClientToolchainCoordinator.ts

@@ -87,7 +87,16 @@ export class LanguageClientToolchainCoordinator implements vscode.Disposable {
      * @returns
      */
     public get(folder: FolderContext): LanguageClientManager {
-        const client = this.clients.get(folder.swiftVersion.toString());
+        return this.getByVersion(folder.swiftVersion.toString());
+    }
+
+    /**
+     * Returns the LanguageClientManager for the supplied toolchain version.
+     * @param folder
+     * @returns
+     */
+    public getByVersion(version: string): LanguageClientManager {
+        const client = this.clients.get(version);
         if (!client) {
             throw new Error(
                 "LanguageClientManager has not yet been created. This is a bug, please file an issue at https://github.com/swiftlang/vscode-swift/issues"