From 3c0d3ba23aa339037630ce735d06b04abdfd1a99 Mon Sep 17 00:00:00 2001
From: Ale Mercado <maria.mercado@slack-corp.com>
Date: Tue, 5 May 2026 16:43:48 -0400
Subject: [PATCH 1/2] feat: add BlockChunk type to
 chat.{start,append,stop}Stream methods

---
 slack_sdk/models/messages/chunk.py    | 26 +++++++++++++++
 tests/slack_sdk/models/test_chunks.py | 46 ++++++++++++++++++++++++++-
 2 files changed, 71 insertions(+), 1 deletion(-)

diff --git a/slack_sdk/models/messages/chunk.py b/slack_sdk/models/messages/chunk.py
index 657d95ae4..f016ec905 100644
--- a/slack_sdk/models/messages/chunk.py
+++ b/slack_sdk/models/messages/chunk.py
@@ -3,6 +3,7 @@
 
 from slack_sdk.models import show_unknown_key_warning
 from slack_sdk.models.basic_objects import JsonObject
+from slack_sdk.models.blocks import Block
 from slack_sdk.models.blocks.block_elements import UrlSourceElement
 
 
@@ -38,6 +39,8 @@ def parse(cls, chunk: Union[Dict, "Chunk"]) -> Optional["Chunk"]:
                     return PlanUpdateChunk(**chunk)
                 elif type == TaskUpdateChunk.type:
                     return TaskUpdateChunk(**chunk)
+                elif type == BlocksChunk.type:
+                    return BlocksChunk(**chunk)
                 else:
                     cls.logger.warning(f"Unknown chunk detected and skipped ({chunk})")
                     return None
@@ -132,3 +135,26 @@ def __init__(
         self.details = details
         self.output = output
         self.sources = sources
+
+
+class BlocksChunk(Chunk):
+    type = "blocks"
+
+    @property
+    def attributes(self) -> Set[str]:  # type: ignore[override]
+        return super().attributes.union({"blocks"})
+
+    def __init__(
+        self,
+        *,
+        blocks: Sequence[Union[Dict, Block]],
+        **others: Dict,
+    ):
+        """Used for passing an array of blocks within a streaming message.
+
+        https://docs.slack.dev/messaging/sending-and-scheduling-messages#text-streaming
+        """
+        super().__init__(type=self.type)
+        show_unknown_key_warning(self, others)
+
+        self.blocks = blocks
diff --git a/tests/slack_sdk/models/test_chunks.py b/tests/slack_sdk/models/test_chunks.py
index 78845b307..dd31d467f 100644
--- a/tests/slack_sdk/models/test_chunks.py
+++ b/tests/slack_sdk/models/test_chunks.py
@@ -1,7 +1,8 @@
 import unittest
 
+from slack_sdk.models.blocks import PlainTextObject, SectionBlock
 from slack_sdk.models.blocks.block_elements import UrlSourceElement
-from slack_sdk.models.messages.chunk import MarkdownTextChunk, PlanUpdateChunk, TaskUpdateChunk
+from slack_sdk.models.messages.chunk import BlocksChunk, Chunk, MarkdownTextChunk, PlanUpdateChunk, TaskUpdateChunk
 
 
 class MarkdownTextChunkTests(unittest.TestCase):
@@ -89,3 +90,46 @@ def test_json(self):
                 ],
             },
         )
+
+
+class BlocksChunkTests(unittest.TestCase):
+    def test_json_with_dicts(self):
+        self.assertDictEqual(
+            BlocksChunk(
+                blocks=[
+                    {"type": "section", "text": {"type": "plain_text", "text": "Hello"}},
+                ]
+            ).to_dict(),
+            {
+                "type": "blocks",
+                "blocks": [
+                    {"type": "section", "text": {"type": "plain_text", "text": "Hello"}},
+                ],
+            },
+        )
+
+    def test_json_with_block_objects(self):
+        self.assertDictEqual(
+            BlocksChunk(
+                blocks=[
+                    SectionBlock(text=PlainTextObject(text="Hello")),
+                ]
+            ).to_dict(),
+            {
+                "type": "blocks",
+                "blocks": [
+                    {"type": "section", "text": {"type": "plain_text", "text": "Hello"}},
+                ],
+            },
+        )
+
+    def test_parse(self):
+        chunk = Chunk.parse(
+            {
+                "type": "blocks",
+                "blocks": [{"type": "section", "text": {"type": "plain_text", "text": "Hello"}}],
+            }
+        )
+        self.assertIsInstance(chunk, BlocksChunk)
+        self.assertEqual(chunk.type, "blocks")
+        self.assertEqual(len(chunk.blocks), 1)

From 8b8ab8b3b21619065d965c2e1a01fd682814047c Mon Sep 17 00:00:00 2001
From: Ale Mercado <maria.mercado@slack-corp.com>
Date: Wed, 6 May 2026 10:36:27 -0400
Subject: [PATCH 2/2] alphabetize

---
 slack_sdk/models/messages/chunk.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/slack_sdk/models/messages/chunk.py b/slack_sdk/models/messages/chunk.py
index f016ec905..a7dfc4de4 100644
--- a/slack_sdk/models/messages/chunk.py
+++ b/slack_sdk/models/messages/chunk.py
@@ -33,14 +33,14 @@ def parse(cls, chunk: Union[Dict, "Chunk"]) -> Optional["Chunk"]:
         else:
             if "type" in chunk:
                 type = chunk["type"]
-                if type == MarkdownTextChunk.type:
+                if type == BlocksChunk.type:
+                    return BlocksChunk(**chunk)
+                elif type == MarkdownTextChunk.type:
                     return MarkdownTextChunk(**chunk)
                 elif type == PlanUpdateChunk.type:
                     return PlanUpdateChunk(**chunk)
                 elif type == TaskUpdateChunk.type:
                     return TaskUpdateChunk(**chunk)
-                elif type == BlocksChunk.type:
-                    return BlocksChunk(**chunk)
                 else:
                     cls.logger.warning(f"Unknown chunk detected and skipped ({chunk})")
                     return None