fix(web-api): widen Slack Lists message field type

.changeset/slack-lists-message-field.md

@@ -0,0 +1,5 @@
+---
+"@slack/web-api": patch
+---
+
+Fix Slack Lists message field types to allow returned message metadata objects while preserving URL-array request values.

packages/web-api/src/types/request/slackLists.ts

@@ -58,11 +58,49 @@ export interface SlackListsItemFieldLink {
 }
 
 /**
- * @description Message field with message URLs.
+ * @description Message metadata returned for Slack Lists message fields.
+ */
+export interface SlackListsItemMessage {
+  /**
+   * @description URL value for the referenced message.
+   */
+  value?: string;
+  /**
+   * @description Channel containing the referenced message.
+   */
+  channel_id?: string;
+  /**
+   * @description Timestamp of the referenced message.
+   */
+  ts?: string;
+  /**
+   * @description Thread timestamp of the referenced message.
+   */
+  thread_ts?: string;
+  /**
+   * @description Plain text fallback returned by some message field responses.
+   */
+  text?: string;
+  /**
+   * @description User ID associated with the referenced message.
+   */
+  user?: string;
+  /**
+   * @description Team ID associated with the referenced message.
+   */
+  team?: string;
+  /**
+   * @description Message type returned by the API.
+   */
+  type?: string;
+}
+
+/**
+ * @description Message field with request message URLs or returned message metadata.
  */
 export interface SlackListsItemFieldMessage {
   column_id: string;
-  message: string[];
+  message: string[] | SlackListsItemMessage | SlackListsItemMessage[];
 }
 
 /**

packages/web-api/test/types/methods/slacklists.test-d.ts

@@ -3,6 +3,8 @@ import { expectAssignable, expectError } from 'tsd';
 import { WebClient } from '../../../src/WebClient';
 
 const web = new WebClient('TOKEN');
+type SlackListsItemsListResponse = Awaited<ReturnType<typeof web.slackLists.items.list>>;
+type SlackListsItemField = NonNullable<SlackListsItemsListResponse['items']>[number]['fields'][number];
 
 // slackLists.access.delete
 // -- sad path
@@ -77,9 +79,35 @@ expectError(web.slackLists.items.create({})); // missing list_id
 expectAssignable<Parameters<typeof web.slackLists.items.create>>([
   {
     list_id: 'L1234567890',
+    initial_fields: [
+      {
+        column_id: 'Col1234567890',
+        message: ['https://example.slack.com/archives/C1234567890/p1234567890123456'],
+      },
+    ],
   },
 ]);
 
+expectAssignable<SlackListsItemField>({
+  column_id: 'Col1234567890',
+  message: {
+    text: 'hello',
+    ts: '123.456',
+    user: 'U0123456789',
+  },
+});
+
+expectAssignable<SlackListsItemField>({
+  column_id: 'Col1234567890',
+  message: [
+    {
+      value: 'https://example.slack.com/archives/C1234567890/p1234567890123456',
+      channel_id: 'C1234567890',
+      ts: '1234567890.123456',
+    },
+  ],
+});
+
 // slackLists.items.delete
 // -- sad path
 expectError(web.slackLists.items.delete()); // lacking argument