fix(app): support text attachments (#17335)

packages/ui/src/components/message-file.test.ts

@@ -0,0 +1,55 @@
+import { describe, expect, test } from "bun:test"
+import type { FilePart } from "@opencode-ai/sdk/v2"
+import { attached, inline, kind } from "./message-file"
+
+function file(part: Partial<FilePart> = {}): FilePart {
+  return {
+    id: "part_1",
+    sessionID: "ses_1",
+    messageID: "msg_1",
+    type: "file",
+    mime: "text/plain",
+    url: "file:///repo/README.txt",
+    filename: "README.txt",
+    ...part,
+  }
+}
+
+describe("message-file", () => {
+  test("treats data URLs as attachments", () => {
+    expect(attached(file({ url: "data:text/plain;base64,SGVsbG8=" }))).toBe(true)
+    expect(attached(file())).toBe(false)
+  })
+
+  test("treats only non-attachment source ranges as inline references", () => {
+    expect(
+      inline(
+        file({
+          source: {
+            type: "file",
+            path: "/repo/README.txt",
+            text: { value: "@README.txt", start: 0, end: 11 },
+          },
+        }),
+      ),
+    ).toBe(true)
+
+    expect(
+      inline(
+        file({
+          url: "data:text/plain;base64,SGVsbG8=",
+          source: {
+            type: "file",
+            path: "/repo/README.txt",
+            text: { value: "@README.txt", start: 0, end: 11 },
+          },
+        }),
+      ),
+    ).toBe(false)
+  })
+
+  test("separates image and file attachment kinds", () => {
+    expect(kind(file({ mime: "image/png" }))).toBe("image")
+    expect(kind(file({ mime: "application/pdf" }))).toBe("file")
+  })
+})