fix(lsp): reset safety block on server restart to prevent permanent blocks (#1366)

src/tools/lsp/client.test.ts

@@ -2,7 +2,7 @@ import { mkdtempSync, rmSync, writeFileSync } from "node:fs"
 import { join } from "node:path"
 import { tmpdir } from "node:os"
 
-import { describe, it, expect, spyOn, mock } from "bun:test"
+import { describe, it, expect, spyOn, mock, beforeEach, afterEach } from "bun:test"
 
 mock.module("vscode-jsonrpc/node", () => ({
   createMessageConnection: () => {
@@ -12,10 +12,18 @@ mock.module("vscode-jsonrpc/node", () => ({
   StreamMessageWriter: function StreamMessageWriter() {},
 }))
 
-import { LSPClient, validateCwd } from "./client"
+import { LSPClient, lspManager, validateCwd } from "./client"
 import type { ResolvedServer } from "./types"
 
 describe("LSPClient", () => {
+  beforeEach(async () => {
+    await lspManager.stopAll()
+  })
+
+  afterEach(async () => {
+    await lspManager.stopAll()
+  })
+
   describe("openFile", () => {
     it("sends didChange when a previously opened file changes on disk", async () => {
       // #given
@@ -61,6 +69,108 @@ describe("LSPClient", () => {
     })
   })
 
+  describe("LSPServerManager", () => {
+    it("recreates client after init failure instead of staying permanently blocked", async () => {
+      //#given
+      const dir = mkdtempSync(join(tmpdir(), "lsp-manager-test-"))
+
+      const server: ResolvedServer = {
+        id: "typescript",
+        command: ["typescript-language-server", "--stdio"],
+        extensions: [".ts"],
+        priority: 0,
+      }
+
+      const startSpy = spyOn(LSPClient.prototype, "start")
+      const initializeSpy = spyOn(LSPClient.prototype, "initialize")
+      const isAliveSpy = spyOn(LSPClient.prototype, "isAlive")
+      const stopSpy = spyOn(LSPClient.prototype, "stop")
+
+      startSpy.mockImplementationOnce(async () => {
+        throw new Error("boom")
+      })
+      startSpy.mockImplementation(async () => {})
+      initializeSpy.mockImplementation(async () => {})
+      isAliveSpy.mockImplementation(() => true)
+      stopSpy.mockImplementation(async () => {})
+
+      try {
+        //#when
+        await expect(lspManager.getClient(dir, server)).rejects.toThrow("boom")
+
+        const client = await lspManager.getClient(dir, server)
+
+        //#then
+        expect(client).toBeInstanceOf(LSPClient)
+        expect(startSpy).toHaveBeenCalledTimes(2)
+        expect(stopSpy).toHaveBeenCalled()
+      } finally {
+        startSpy.mockRestore()
+        initializeSpy.mockRestore()
+        isAliveSpy.mockRestore()
+        stopSpy.mockRestore()
+        rmSync(dir, { recursive: true, force: true })
+      }
+    })
+
+    it("resets stale initializing entry so a hung init does not permanently block future clients", async () => {
+      //#given
+      const dir = mkdtempSync(join(tmpdir(), "lsp-manager-stale-test-"))
+
+      const server: ResolvedServer = {
+        id: "typescript",
+        command: ["typescript-language-server", "--stdio"],
+        extensions: [".ts"],
+        priority: 0,
+      }
+
+      const dateNowSpy = spyOn(Date, "now")
+
+      const startSpy = spyOn(LSPClient.prototype, "start")
+      const initializeSpy = spyOn(LSPClient.prototype, "initialize")
+      const isAliveSpy = spyOn(LSPClient.prototype, "isAlive")
+      const stopSpy = spyOn(LSPClient.prototype, "stop")
+
+      // First client init hangs forever.
+      const never = new Promise<void>(() => {})
+      startSpy.mockImplementationOnce(async () => {
+        await never
+      })
+
+      // Second attempt should be allowed after stale reset.
+      startSpy.mockImplementationOnce(async () => {})
+      startSpy.mockImplementation(async () => {})
+      initializeSpy.mockImplementation(async () => {})
+      isAliveSpy.mockImplementation(() => true)
+      stopSpy.mockImplementation(async () => {})
+
+      try {
+        //#when
+        dateNowSpy.mockReturnValueOnce(0)
+        lspManager.warmupClient(dir, server)
+
+        dateNowSpy.mockReturnValueOnce(60_000)
+
+        const client = await Promise.race([
+          lspManager.getClient(dir, server),
+          new Promise<never>((_, reject) => setTimeout(() => reject(new Error("test-timeout")), 50)),
+        ])
+
+        //#then
+        expect(client).toBeInstanceOf(LSPClient)
+        expect(startSpy).toHaveBeenCalledTimes(2)
+        expect(stopSpy).toHaveBeenCalled()
+      } finally {
+        dateNowSpy.mockRestore()
+        startSpy.mockRestore()
+        initializeSpy.mockRestore()
+        isAliveSpy.mockRestore()
+        stopSpy.mockRestore()
+        rmSync(dir, { recursive: true, force: true })
+      }
+    })
+  })
+
   describe("validateCwd", () => {
     it("returns valid for existing directory", () => {
       // #given