Merge pull request #10786 from Kilo-Org/foul-oval

fix(cli): skip background port scans in VS Code

.changeset/calm-background-process-scans.md

@@ -0,0 +1,6 @@
+---
+"@kilocode/cli": patch
+"kilo-code": patch
+---
+
+Skip inferred background-process port scanning in VS Code sessions to avoid unnecessary Bun subprocess polling.

packages/opencode/src/kilocode/background-process/index.ts

@@ -8,6 +8,7 @@ import { SessionID } from "@/session/schema"
 import { Shell } from "@/shell/shell"
 import { NonNegativeInt, PositiveInt, optionalOmitUndefined, withStatics } from "@/util/schema"
 import { zod, ZodOverride } from "@/util/effect-zod"
+import { Flag } from "@opencode-ai/core/flag/flag"
 import * as Log from "@opencode-ai/core/util/log"
 import { spawn, type ChildProcess } from "child_process"
 import { Context, Effect, Layer, Schema, Types } from "effect"
@@ -172,7 +173,8 @@ export namespace BackgroundProcess {
       return changed
     }
     const fallback = active.info.ready && active.start.ready?.port ? [active.start.ready.port] : []
-    const next = Array.from(new Set([...(await Ports.list(pid)), ...fallback])).toSorted((a, b) => a - b)
+    const ports = Flag.KILO_CLIENT === "cli" ? await Ports.list(pid) : []
+    const next = Array.from(new Set([...ports, ...fallback])).toSorted((a, b) => a - b)
     if (same(active.info.ports, next)) return false
     active.info.ports = next
     active.info.time.updated = Date.now()
@@ -209,6 +211,7 @@ export namespace BackgroundProcess {
 
   function poll(active: Active) {
     if (active.disposed) return
+    if (Flag.KILO_CLIENT !== "cli") return
     if (terminal(active.info.status)) return
     if (active.poll) return
     active.poll = setTimeout(() => {

packages/opencode/test/kilocode/background-process.test.ts

@@ -23,6 +23,14 @@ async function script(dir: string, name: string, source: string) {
   return `${bin} ${arg}`
 }
 
+function port() {
+  const server = Bun.serve({ hostname: "127.0.0.1", port: 0, fetch: () => new Response() })
+  const port = server.port
+  server.stop(true)
+  if (!port) throw new Error("Failed to reserve port")
+  return port
+}
+
 function update(sessionID: SessionID) {
   const state: { off?: () => void; timer?: ReturnType<typeof setTimeout> } = {}
   const promise = new Promise<BackgroundProcess.Info>((resolve, reject) => {
@@ -92,6 +100,119 @@ setInterval(() => {}, 1_000)
     }),
   )
 
+  it.instance("reports explicit readiness ports for VS Code clients", () =>
+    Effect.gen(function* () {
+      const test = yield* TestInstance
+      const sessionID = SessionID.descending()
+      const listen = port()
+      const command = yield* Effect.promise(() =>
+        script(
+          test.directory,
+          "vscode-ready-port.mjs",
+          `Bun.serve({ hostname: "127.0.0.1", port: ${listen}, fetch: () => new Response() })
+`,
+        ),
+      )
+      const client = process.env["KILO_CLIENT"]
+      process.env["KILO_CLIENT"] = "vscode"
+
+      try {
+        const info = yield* Effect.promise(() =>
+          BackgroundProcess.start({
+            sessionID,
+            command,
+            cwd: test.directory,
+            ready: { port: listen, timeout: 5_000 },
+          }),
+        )
+
+        expect(info.status).toBe("ready")
+        expect(info.ports).toEqual([listen])
+      } finally {
+        yield* Effect.promise(() => BackgroundProcess.stopSession(sessionID))
+        if (client === undefined) delete process.env["KILO_CLIENT"]
+        else process.env["KILO_CLIENT"] = client
+      }
+    }),
+  )
+
+  it.instance("infers ports for CLI clients", () =>
+    Effect.gen(function* () {
+      const test = yield* TestInstance
+      const sessionID = SessionID.descending()
+      const listen = port()
+      const command = yield* Effect.promise(() =>
+        script(
+          test.directory,
+          "cli-port.mjs",
+          `Bun.serve({ hostname: "127.0.0.1", port: ${listen}, fetch: () => new Response() })
+`,
+        ),
+      )
+      const client = process.env["KILO_CLIENT"]
+      process.env["KILO_CLIENT"] = "cli"
+
+      try {
+        const info = yield* Effect.promise(() =>
+          BackgroundProcess.start({
+            sessionID,
+            command,
+            cwd: test.directory,
+          }),
+        )
+
+        let found = yield* Effect.promise(() => BackgroundProcess.get(info.id))
+        if (process.platform !== "win32") {
+          for (let attempt = 0; attempt < 40 && !found?.ports.includes(listen); attempt++) {
+            yield* Effect.promise(() => Bun.sleep(250))
+            found = yield* Effect.promise(() => BackgroundProcess.get(info.id))
+          }
+        }
+        expect(found?.ports).toEqual(process.platform === "win32" ? [] : [listen])
+      } finally {
+        yield* Effect.promise(() => BackgroundProcess.stopSession(sessionID))
+        if (client === undefined) delete process.env["KILO_CLIENT"]
+        else process.env["KILO_CLIENT"] = client
+      }
+    }),
+  )
+
+  it.instance("does not infer ports for VS Code clients", () =>
+    Effect.gen(function* () {
+      const test = yield* TestInstance
+      const sessionID = SessionID.descending()
+      const listen = port()
+      const command = yield* Effect.promise(() =>
+        script(
+          test.directory,
+          "vscode-port.mjs",
+          `Bun.serve({ hostname: "127.0.0.1", port: ${listen}, fetch: () => new Response() })
+`,
+        ),
+      )
+      const client = process.env["KILO_CLIENT"]
+      process.env["KILO_CLIENT"] = "vscode"
+
+      try {
+        const info = yield* Effect.promise(() =>
+          BackgroundProcess.start({
+            sessionID,
+            command,
+            cwd: test.directory,
+          }),
+        )
+
+        yield* Effect.promise(() => Bun.sleep(2_500))
+        const found = yield* Effect.promise(() => BackgroundProcess.get(info.id))
+        expect(found?.ports).toEqual([])
+      } finally {
+        yield* Effect.promise(() => BackgroundProcess.stopSession(sessionID))
+        if (client === undefined) delete process.env["KILO_CLIENT"]
+        else process.env["KILO_CLIENT"] = client
+      }
+    }),
+  )
+
   it.instance("publishes output updates from process callbacks", () =>
     Effect.gen(function* () {
       const test = yield* TestInstance