feat(desktop): open attachments in active project (#31192)

packages/app/src/components/prompt-input/attachments.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, test } from "bun:test"
-import { attachmentMime } from "./files"
+import { attachmentMime, pickAttachmentFiles } from "./files"
 import { pasteMode } from "./paste"
 
 describe("attachmentMime", () => {
@@ -24,6 +24,70 @@ describe("attachmentMime", () => {
   })
 })
 
+describe("pickAttachmentFiles", () => {
+  test("reads the current project directory for every native picker invocation", async () => {
+    const paths: string[] = []
+    const files: File[] = []
+    const file = new File(["hello"], "hello.txt", { type: "text/plain" })
+    let directory = "C:\\Projects\\LoremIpsum"
+    const picker = async (options?: { defaultPath?: string }, onFile?: (file: File) => Promise<unknown>) => {
+      paths.push(options?.defaultPath ?? "")
+      await onFile?.(file)
+    }
+
+    pickAttachmentFiles({
+      picker,
+      directory: () => directory,
+      fallback: () => undefined,
+      onFile: async (selected) => files.push(selected),
+      onError: () => undefined,
+    })
+    await Promise.resolve()
+    directory = "C:\\Projects\\DolorSit"
+    pickAttachmentFiles({
+      picker,
+      directory: () => directory,
+      fallback: () => undefined,
+      onFile: async (selected) => files.push(selected),
+      onError: () => undefined,
+    })
+    await Promise.resolve()
+    expect(files).toEqual([file, file])
+    expect(paths).toEqual(["C:\\Projects\\LoremIpsum", "C:\\Projects\\DolorSit"])
+  })
+
+  test("uses the browser file input when no native picker exists", async () => {
+    let fallback = 0
+    pickAttachmentFiles({
+      directory: () => "/projects/consectetur-adipiscing",
+      fallback: () => {
+        fallback += 1
+      },
+      onFile: async () => undefined,
+      onError: () => undefined,
+    })
+    expect(fallback).toBe(1)
+  })
+
+  test("reports native picker failures without rejecting", async () => {
+    const error = new Error("picker unavailable")
+    const errors: unknown[] = []
+    const handled = Promise.withResolvers<void>()
+    pickAttachmentFiles({
+      picker: async () => Promise.reject(error),
+      directory: () => "C:\\Projects\\LoremIpsum",
+      fallback: () => undefined,
+      onFile: async () => undefined,
+      onError: (cause) => {
+        errors.push(cause)
+        handled.resolve()
+      },
+    })
+    await handled.promise
+    expect(errors).toEqual([error])
+  })
+})
+
 describe("pasteMode", () => {
   test("uses native paste for short single-line text", () => {
     expect(pasteMode("hello world")).toBe("native")

packages/app/src/components/prompt-input/files.ts

@@ -2,6 +2,35 @@ import { ACCEPTED_FILE_TYPES, ACCEPTED_IMAGE_TYPES } from "@/constants/file-pick
 
 export { ACCEPTED_FILE_TYPES }
 
+type AttachmentPicker = (options: {
+  defaultPath?: string
+  multiple?: boolean
+  accept?: string[]
+}, onFile: (file: File) => Promise<unknown>) => Promise<void>
+
+export function pickAttachmentFiles(input: {
+  picker?: AttachmentPicker
+  directory: () => string
+  fallback: () => void
+  onFile: (file: File) => Promise<unknown>
+  onError: (error: unknown) => void
+}) {
+  if (!input.picker) {
+    input.fallback()
+    return
+  }
+  void input
+    .picker(
+      {
+        defaultPath: input.directory(),
+        multiple: true,
+        accept: ACCEPTED_FILE_TYPES,
+      },
+      input.onFile,
+    )
+    .catch(input.onError)
+}
+
 const IMAGE_MIMES = new Set(ACCEPTED_IMAGE_TYPES)
 const IMAGE_EXTS = new Map([
   ["gif", "image/gif"],