feat(tools): pick among interchangeable language servers for every language (#313)

A language server and the fallback servers after it in languages/*.toml now share one picker in the Language Servers details pane, for every language rather than Python only: Language server for <languages>: Automatic, each server (with its status) or None, with the Automatic order in the hint. Servers outside such a group keep their on/off checkbox. ToolInfo.alternatives lists each server's group in preference order; a regular server after a fallback starts no group with it. The Python-only picker at the top of the page is removed, and names drop a language suffix the label already states. Storage is unchanged (each server's enabled flag, global or project scope), so existing settings carry over.

crates/ide-tools/src/lib.rs

@@ -77,6 +77,9 @@ pub struct ToolInfo {
     pub default_args: Vec<String>,
     /// A language server's `initializationOptions` from its language definition, as JSON text.
     pub default_initialization_options: Option<String>,
+    /// The interchangeable servers this one belongs to, in preference order: a
+    /// server and the `fallback` ones after it. Empty when it has none.
+    pub alternatives: Vec<String>,
 }
 
 /// Streamed install progress.
@@ -224,6 +227,7 @@ struct Usage {
     install_hint: Option<String>,
     args: Vec<String>,
     initialization_options: Option<String>,
+    alternatives: Vec<String>,
 }
 
 fn usages(langs: &[LanguageConfig]) -> BTreeMap<String, Usage> {
@@ -266,6 +270,23 @@ fn usages(langs: &[LanguageConfig]) -> BTreeMap<String, Usage> {
                 s.initialization_options.as_ref().and_then(|v| serde_json::to_value(v).ok()).map(|v| v.to_string());
         }
     }
+    for l in langs {
+        let servers = &l.language_servers;
+        for (i, head) in servers.iter().enumerate().filter(|(_, s)| !s.fallback) {
+            let chain: Vec<String> = std::iter::once(head)
+                .chain(servers[i + 1..].iter().take_while(|s| s.fallback))
+                .map(|s| s.name.clone())
+                .collect();
+            if chain.len() < 2 {
+                continue;
+            }
+            for name in &chain {
+                if let Some(u) = map.get_mut(name).filter(|u| u.alternatives.is_empty()) {
+                    u.alternatives = chain.clone();
+                }
+            }
+        }
+    }
     map
 }
 
@@ -480,6 +501,7 @@ impl Tools {
                 custom_error: None,
                 default_args: u.args.clone(),
                 default_initialization_options: u.initialization_options.clone(),
+                alternatives: u.alternatives.clone(),
             })
             .map(|info| self.apply_custom(info, None));
         };
@@ -504,6 +526,7 @@ impl Tools {
             custom_error: None,
             default_args: usage.map(|u| u.args.clone()).unwrap_or_default(),
             default_initialization_options: usage.and_then(|u| u.initialization_options.clone()),
+            alternatives: usage.map(|u| u.alternatives.clone()).unwrap_or_default(),
         })
         .map(|info| self.apply_custom(info, Some(spec)))
     }

crates/ide-tools/src/tests.rs

@@ -88,6 +88,20 @@ fn everything_missing_on_an_empty_system() {
     assert!(find(&list, "delve").kind == ToolKind::Debugger);
 }
 
+#[test]
+fn interchangeable_servers_list_their_alternatives() {
+    let env = Env::new();
+    let list = env.tools().list(&langs());
+    let python = ["basedpyright", "pyright", "ty"];
+    for name in python {
+        assert_eq!(find(&list, name).alternatives, python);
+    }
+    assert_eq!(find(&list, "vtsls").alternatives, ["vtsls", "typescript-language-server"]);
+    // A regular server after a fallback starts no group with it.
+    assert!(find(&list, "angular-language-server").alternatives.is_empty());
+    assert!(find(&list, "rust-analyzer").alternatives.is_empty());
+}
+
 #[cfg(unix)]
 #[test]
 fn detects_tools_on_path_with_versions() {

src/bindings.ts

@@ -5890,6 +5890,11 @@ export type ToolInfo = {
 	defaultArgs: string[],
 	/**  A language server's `initializationOptions` from its language definition, as JSON text. */
 	defaultInitializationOptions: string | null,
+	/**
+	 *  The interchangeable servers this one belongs to, in preference order: a
+	 *  server and the `fallback` ones after it. Empty when it has none.
+	 */
+	alternatives: string[],
 };
 
 export type ToolKind = "languageServer" | "debugger" | 

src/features/tools/LanguageServersPage.module.css

@@ -11,21 +11,6 @@
   max-width: 680px;
   color: var(--fg-secondary);
 }
-.pythonAnalyzer {
-  display: flex;
-  flex-direction: column;
-  gap: 4px;
-}
-.pythonAnalyzerRow {
-  display: flex;
-  align-items: center;
-  gap: 10px;
-}
-.pythonAnalyzerHint {
-  margin: 0;
-  color: var(--fg-secondary);
-  font-size: var(--fs-small);
-}
 .body {
   display: flex;
   flex: 1;

src/features/tools/LanguageServersPage.tsx

@@ -8,7 +8,7 @@
 import { useEffect, useMemo, useState, type KeyboardEvent } from "react";
 import clsx from "clsx";
 import type { ToolInfo } from "@/bindings";
-import { Badge, Button, EmptyState, IconButton, ProgressBar, SearchField, Select, Spinner, T } from "@/ui";
+import { Badge, Button, EmptyState, IconButton, ProgressBar, SearchField, Spinner, T } from "@/ui";
 import { onIdeEvent } from "@/platform/ipc";
 import { useProject } from "@/platform/project";
 import { useSettingsForm } from "@/workbench/contributions";
@@ -28,25 +28,6 @@ import { tx } from "@/platform/i18n";
 
 type Filter = "all" | "missing" | "installed";
 
-const PYTHON_ANALYZERS = ["basedpyright", "pyright", "ty"] as const;
-type PythonAnalyzer = (typeof PYTHON_ANALYZERS)[number] | "auto" | "none" | "custom";
-
-function selectedPythonAnalyzer(servers: Record<string, ServerEntry>): PythonAnalyzer {
-  const enabled = PYTHON_ANALYZERS.filter((name) => servers[name]?.enabled !== false);
-  if (enabled.length === PYTHON_ANALYZERS.length) return "auto";
-  if (enabled.length === 0) return "none";
-  return enabled.length === 1 ? enabled[0]! : "custom";
-}
-
-const PYTHON_ANALYZER_OPTIONS: ReadonlyArray<{ value: PythonAnalyzer; label: string; disabled?: boolean }> = [
-  { value: "auto", label: "Automatic (first available)" },
-  { value: "basedpyright", label: "basedpyright" },
-  { value: "pyright", label: "Pyright" },
-  { value: "ty", label: "ty" },
-  { value: "none", label: "None" },
-  { value: "custom", label: "Custom combination", disabled: true },
-];
-
 const STATUS_TONE: Record<ToolInfo["status"], "success" | "accent" | "warning"> = {
   installed: "success",
   onPath: "accent",
@@ -90,6 +71,7 @@ function pendingTool(name: string, entry: ServerEntry, languages: string[]): Too
     customError: null,
     defaultArgs: [],
     defaultInitializationOptions: null,
+    alternatives: [],
   };
 }
 
@@ -336,29 +318,6 @@ export function LanguageServersPage() {
           "Language servers and debug adapters used by the IDE. Missing tools can be installed into the IDE's own tools folder; nothing is downloaded until you click Install.",
         )}
       </p>
-      <div className={styles.pythonAnalyzer}>
-        <div className={styles.pythonAnalyzerRow}>
-          <span>
-            <T>Python language server</T>
-          </span>
-          <Select
-            aria-label="Python language server"
-            value={selectedPythonAnalyzer(servers)}
-            options={PYTHON_ANALYZER_OPTIONS}
-            onChange={(selected) => {
-              if (selected === "custom") return;
-              for (const name of PYTHON_ANALYZERS) {
-                const on = selected === "auto" || selected === name;
-                // Same as each server's own checkbox: on is the default, so only a project spells it out.
-                form.set(serverKey(name, "enabled"), on ? (form.scope === "project" ? true : null) : false);
-              }
-            }}
-          />
-        </div>
-        <p className={styles.pythonAnalyzerHint}>
-          <T>Only one of these built-in Python analyzers runs at a time.</T>
-        </p>
-      </div>
       {error && (
         <div className={styles.error} role="alert">
           {error}

src/features/tools/ServerSettings.tsx

@@ -7,7 +7,7 @@
 import { useEffect, useId, useMemo, useRef, useState, type ReactNode } from "react";
 import clsx from "clsx";
 import type { ToolInfo } from "@/bindings";
-import { Checkbox, Dialog, Icon, IconButton, Input, Popup, SearchField, T } from "@/ui";
+import { Checkbox, Dialog, Icon, IconButton, Input, Popup, SearchField, Select, T } from "@/ui";
 import { tx } from "@/platform/i18n";
 import { useSettingsForm } from "@/workbench/contributions";
 import { toolsBackend, type LanguageChoice } from "./backend";
@@ -27,6 +27,7 @@ import {
   type ServerEntry,
   type ServerField,
 } from "./serverConfig";
+import { STATUS_LABEL, useTools } from "./store";
 import styles from "./ServerSettings.module.css";
 
 let languageList: Promise<LanguageChoice[]> | null = null;
@@ -352,6 +353,66 @@ export function ToolSettings({ tool }: { tool: ToolInfo }) {
   );
 }
 
+/**
+ * Interchangeable servers (a server and its `fallback`s): one picker for the
+ * group instead of an on/off box per server. Automatic keeps them all on, so
+ * the first one available runs.
+ */
+function AlternativesRow({ tool }: { tool: ToolInfo }) {
+  const form = useSettingsForm();
+  const tools = useTools((s) => s.tools);
+  const servers = (form.useValue("languageServers") ?? {}) as Record<string, ServerEntry>;
+  const names = tool.alternatives;
+  const members = names.map((name) => tools.find((t) => t.name === name));
+  const common = members.reduce<string[]>(
+    (acc, t) => (t ? acc.filter((l) => t.languages.includes(l)) : acc),
+    tool.languages,
+  );
+  const languages = common.join(", ");
+  // "ty (Python)" is just "ty" next to "Language server for Python".
+  const short = names.map((name, i) => {
+    const display = members[i]?.displayName ?? name;
+    const suffix = /^(.*) \((.+)\)$/.exec(display);
+    return suffix && common.includes(suffix[2]!) ? suffix[1]! : display;
+  });
+  const enabled = names.filter((name) => servers[name]?.enabled !== false);
+  const value =
+    enabled.length === names.length
+      ? "auto"
+      : enabled.length === 0
+        ? "none"
+        : enabled.length === 1
+          ? enabled[0]!
+          : null;
+  const options = [
+    { value: "auto", label: tx("Automatic") },
+    ...names.map((name, i) => {
+      const t = members[i];
+      return { value: name, label: short[i]!, detail: t ? tx(STATUS_LABEL[t.status]) : undefined };
+    }),
+    { value: "none", label: tx("None") },
+  ];
+  const order = short.join(" → ");
+  const label = languages ? tx`Language server for ${languages}` : tx("Language server");
+  return (
+    <Row label={label} hint={tx`Only one of these runs at a time. Automatic uses the first one available: ${order}.`}>
+      <Select
+        aria-label={label}
+        value={value}
+        placeholder={tx("Custom combination")}
+        options={options}
+        onChange={(choice) => {
+          for (const name of names) {
+            const on = choice === "auto" || choice === name;
+            // Same as the on/off box: on is the default, so only a project spells it out.
+            form.set(serverKey(name, "enabled"), on ? (form.scope === "project" ? true : null) : false);
+          }
+        }}
+      />
+    </Row>
+  );
+}
+
 /** A language server: on/off, executable, startup options, workspace configuration. */
 export function ServerSettings({ tool, pending }: { tool: ToolInfo; pending: boolean }) {
   const form = useSettingsForm();
@@ -372,14 +433,20 @@ export function ServerSettings({ tool, pending }: { tool: ToolInfo; pending: boo
 
   return (
     <div className={styles.form}>
-      <Checkbox
-        checked={entry.enabled !== false}
-        label={
-          languages.length ? tx`Use ${tool.displayName} for ${languages.join(", ")} files` : tx`Use ${tool.displayName}`
-        }
-        // Enabled is the default; a project says so explicitly to win over a global "off".
-        onChange={(on) => set("enabled")(on ? (form.scope === "project" ? true : null) : false)}
-      />
+      {tool.alternatives.length > 1 ? (
+        <AlternativesRow tool={tool} />
+      ) : (
+        <Checkbox
+          checked={entry.enabled !== false}
+          label={
+            languages.length
+              ? tx`Use ${tool.displayName} for ${languages.join(", ")} files`
+              : tx`Use ${tool.displayName}`
+          }
+          // Enabled is the default; a project says so explicitly to win over a global "off".
+          onChange={(on) => set("enabled")(on ? (form.scope === "project" ? true : null) : false)}
+        />
+      )}
 
       <Section title="Executable">
         <ExecutableRow tool={tool} pending={pending} />

src/features/tools/__tests__/serverSettings.test.tsx

@@ -73,13 +73,35 @@ describe("Language Servers page settings", () => {
 
   afterEach(() => setToolsBackend(null));
 
+  const pythonPicker = async (user: ReturnType<typeof userEvent.setup>) => {
+    await waitFor(() => expect(listItem("pyright")).not.toBeNull());
+    await user.click(listItem("pyright")!);
+    // No on/off box: the group's picker replaces it.
+    expect(within(details("Pyright")).queryByRole("checkbox", { name: /^Use Pyright/ })).toBeNull();
+    return within(details("Pyright")).getByRole("button", { name: "Language server for Python" });
+  };
+
+  it("lists one picker per group of interchangeable servers, on each member", async () => {
+    const user = userEvent.setup();
+    renderPage();
+    await pythonPicker(user);
+    await user.click(listItem("ty")!);
+    const ty = details("ty (Python)");
+    expect(within(ty).getByRole("button", { name: "Language server for Python" })).toHaveTextContent("Automatic");
+    // The language is in the label already, so names drop a "(Python)" suffix.
+    expect(within(ty).getByText(/basedpyright → Pyright → ty\.$/)).toBeInTheDocument();
+    await user.click(listItem("gopls")!);
+    expect(within(details("gopls")).getByRole("checkbox", { name: /Use gopls/ })).toBeInTheDocument();
+    expect(within(details("gopls")).queryByRole("button", { name: /^Language server for/ })).toBeNull();
+  });
+
   it("selects exactly one Python analyzer and restores automatic fallback without writing defaults", async () => {
     const user = userEvent.setup();
     renderPage();
-    const picker = screen.getByRole("button", { name: "Python language server" });
+    const picker = await pythonPicker(user);
     expect(picker).toHaveTextContent("Automatic");
     await user.click(picker);
-    await user.click(screen.getByRole("option", { name: "ty" }));
+    await user.click(screen.getByRole("option", { name: /^ty/ }));
     expect(stagedFor("languageServers.basedpyright.enabled")).toBe(false);
     expect(stagedFor("languageServers.pyright.enabled")).toBe(false);
     expect(stagedFor("languageServers.ty.enabled")).toBeNull();
@@ -99,9 +121,9 @@ describe("Language Servers page settings", () => {
         <LanguageServersPage />
       </TestSettingsForm>,
     );
-    const picker = screen.getByRole("button", { name: "Python language server" });
+    const picker = await pythonPicker(user);
     await user.click(picker);
-    await user.click(screen.getByRole("option", { name: "Pyright" }));
+    await user.click(screen.getByRole("option", { name: /^Pyright/ }));
     expect(stagedFor("languageServers.basedpyright.enabled")).toBe(false);
     expect(stagedFor("languageServers.pyright.enabled")).toBe(true);
     expect(stagedFor("languageServers.ty.enabled")).toBe(false);

src/features/tools/backend.ts

@@ -70,6 +70,7 @@ function tool(partial: Partial<ToolInfo> & Pick<ToolInfo, "name" | "languages">)
     customError: null,
     defaultArgs: [],
     defaultInitializationOptions: null,
+    alternatives: [],
     ...partial,
   };
 }
@@ -93,7 +94,15 @@ export function sampleTools(): ToolInfo[] {
       version: "4.3.3",
       path: "/opt/homebrew/bin/typescript-language-server",
     }),
-    tool({ name: "basedpyright", languages: ["Python"], installMethod: "pip (virtualenv)" }),
+    ...["basedpyright", "pyright", "ty"].map((name) =>
+      tool({
+        name,
+        displayName: name === "pyright" ? "Pyright" : name === "ty" ? "ty (Python)" : name,
+        languages: ["Python"],
+        installMethod: "pip (virtualenv)",
+        alternatives: ["basedpyright", "pyright", "ty"],
+      }),
+    ),
     tool({ name: "gopls", languages: ["Go"], installMethod: "go install" }),
     tool({
       name: "delve",

src/platform/locales/text/zh.json

@@ -4555,10 +4555,10 @@
   "Unversioned": "未跟踪",
   "Merge conflict": "合并冲突",
   "by {author}": "由 {author} 创建",
-  "Automatic (first available)": "自动（第一个可用的）",
+  "Automatic": "自动",
   "Custom combination": "自定义组合",
-  "Python language server": "Python 语言服务器",
-  "Only one of these built-in Python analyzers runs at a time.": "这些内置 Python 分析器同一时间只运行一个。",
+  "Language server for {languages}": "{languages} 语言服务器",
+  "Only one of these runs at a time. Automatic uses the first one available: {order}.": "这些服务器同一时间只运行一个。自动模式使用第一个可用的：{order}。",
   "Configure the settings related to version control used in your project": "配置项目中使用的版本控制相关设置",
   "Use non-modal commit interface": "使用非模态提交界面",
   "When off, Local Changes and Stash are tabs of the Git tool window and Commit opens a dialog.": "关闭时，本地更改和贮藏作为 Git 工具窗口的标签页显示，提交时打开对话框。",