fix(lsp): handle optional requests to avoid MethodNotFound (-32601) with MATLAB Language Server (#4007)

packages/opencode/test/lsp/client.test.ts

@@ -0,0 +1,95 @@
+import { describe, expect, test, beforeEach } from "bun:test"
+import path from "path"
+import { LSPClient } from "../../src/lsp/client"
+import { LSPServer } from "../../src/lsp/server"
+import { Instance } from "../../src/project/instance"
+import { Log } from "../../src/util/log"
+
+// Minimal fake LSP server that speaks JSON-RPC over stdio
+function spawnFakeServer() {
+  const { spawn } = require("child_process")
+  const serverPath = path.join(__dirname, "../fixture/lsp/fake-lsp-server.js")
+  return {
+    process: spawn(process.execPath, [serverPath], {
+      stdio: "pipe",
+    }),
+  }
+}
+
+describe("LSPClient interop", () => {
+  beforeEach(async () => {
+    await Log.init({ print: true })
+  })
+
+  test("handles workspace/workspaceFolders request", async () => {
+    const handle = spawnFakeServer() as any
+
+    const client = await Instance.provide({
+      directory: process.cwd(),
+      fn: () =>
+        LSPClient.create({
+          serverID: "fake",
+          server: handle as unknown as LSPServer.Handle,
+          root: process.cwd(),
+        }),
+    })
+
+    await client.connection.sendNotification("test/trigger", {
+      method: "workspace/workspaceFolders",
+    })
+
+    await new Promise((r) => setTimeout(r, 100))
+
+    expect(client.connection).toBeDefined()
+
+    await client.shutdown()
+  })
+
+  test("handles client/registerCapability request", async () => {
+    const handle = spawnFakeServer() as any
+
+    const client = await Instance.provide({
+      directory: process.cwd(),
+      fn: () =>
+        LSPClient.create({
+          serverID: "fake",
+          server: handle as unknown as LSPServer.Handle,
+          root: process.cwd(),
+        }),
+    })
+
+    await client.connection.sendNotification("test/trigger", {
+      method: "client/registerCapability",
+    })
+
+    await new Promise((r) => setTimeout(r, 100))
+
+    expect(client.connection).toBeDefined()
+
+    await client.shutdown()
+  })
+
+  test("handles client/unregisterCapability request", async () => {
+    const handle = spawnFakeServer() as any
+
+    const client = await Instance.provide({
+      directory: process.cwd(),
+      fn: () =>
+        LSPClient.create({
+          serverID: "fake",
+          server: handle as unknown as LSPServer.Handle,
+          root: process.cwd(),
+        }),
+    })
+
+    await client.connection.sendNotification("test/trigger", {
+      method: "client/unregisterCapability",
+    })
+
+    await new Promise((r) => setTimeout(r, 100))
+
+    expect(client.connection).toBeDefined()
+
+    await client.shutdown()
+  })
+})