chore: import upstream snapshot with attribution

python/assistant-stream/tests/test_state_updates.py

@@ -0,0 +1,164 @@
+from typing import Any
+
+import pytest
+
+from assistant_stream import RunController, create_run
+from assistant_stream.state_manager import StateManager
+
+
+@pytest.mark.anyio
+async def test_append_text_helper_emits_append_text_op() -> None:
+    ops: list[dict[str, Any]] = []
+    manager = StateManager(
+        lambda chunk: ops.extend(chunk.operations),
+        {"messages": [{"text": ""}]},
+    )
+
+    manager.append_text(["messages", "0", "text"], "hi")
+    manager.flush()
+
+    assert ops == [{"type": "append-text", "path": ["messages", "0", "text"], "value": "hi"}]
+
+
+@pytest.mark.anyio
+async def test_nested_plus_equals_on_string_emits_append_text() -> None:
+    ops: list[dict[str, Any]] = []
+    manager = StateManager(
+        lambda chunk: ops.extend(chunk.operations),
+        {"messages": [{"text": "h"}]},
+    )
+
+    manager.state["messages"][0]["text"] += "i"
+    manager.flush()
+
+    assert ops == [
+        {"type": "append-text", "path": ["messages", "0", "text"], "value": "i"}
+    ]
+
+
+@pytest.mark.anyio
+async def test_nested_plus_equals_multiple_operations_accumulate() -> None:
+    ops: list[dict[str, Any]] = []
+    manager = StateManager(
+        lambda chunk: ops.extend(chunk.operations),
+        {"messages": [{"text": ""}]},
+    )
+
+    manager.state["messages"][0]["text"] += "Hel"
+    manager.state["messages"][0]["text"] += "lo"
+    manager.flush()
+
+    assert ops == [
+        {"type": "set", "path": ["messages", "0", "text"], "value": "Hel"},
+        {"type": "append-text", "path": ["messages", "0", "text"], "value": "lo"},
+    ]
+    assert manager.state_data["messages"][0]["text"] == "Hello"
+
+
+@pytest.mark.anyio
+async def test_streaming_path_emits_append_text_deltas_not_set() -> None:
+    async def run_callback(controller: RunController):
+        controller.append_state_text(["messages", 0, "text"], "Hel")
+        controller.append_state_text(["messages", 0, "text"], "lo")
+
+    chunks = [
+        chunk
+        async for chunk in create_run(
+            run_callback, state={"messages": [{"text": ""}]}
+        )
+    ]
+    operations = [
+        operation
+        for chunk in chunks
+        if chunk.type == "update-state"
+        for operation in chunk.operations
+    ]
+
+    assert operations == [
+        {"type": "append-text", "path": ["messages", "0", "text"], "value": "Hel"},
+        {"type": "append-text", "path": ["messages", "0", "text"], "value": "lo"},
+    ]
+
+
+@pytest.mark.anyio
+async def test_string_assignment_non_extension_emits_set() -> None:
+    ops: list[dict[str, Any]] = []
+    manager = StateManager(
+        lambda chunk: ops.extend(chunk.operations),
+        {"messages": [{"text": "hello"}]},
+    )
+
+    manager.state["messages"][0]["text"] = "goodbye"
+    manager.flush()
+
+    assert ops == [{"type": "set", "path": ["messages", "0", "text"], "value": "goodbye"}]
+
+
+@pytest.mark.anyio
+async def test_string_assignment_non_string_override_emits_set() -> None:
+    ops: list[dict[str, Any]] = []
+    manager = StateManager(
+        lambda chunk: ops.extend(chunk.operations),
+        {"messages": [{"text": "hello"}]},
+    )
+
+    manager.state["messages"][0]["text"] = 42
+    manager.flush()
+
+    assert ops == [{"type": "set", "path": ["messages", "0", "text"], "value": 42}]
+
+
+@pytest.mark.anyio
+async def test_string_assignment_unchanged_value_emits_set() -> None:
+    ops: list[dict[str, Any]] = []
+    manager = StateManager(
+        lambda chunk: ops.extend(chunk.operations),
+        {"messages": [{"text": "hello"}]},
+    )
+
+    manager.state["messages"][0]["text"] = "hello"
+    manager.flush()
+
+    assert ops == [{"type": "set", "path": ["messages", "0", "text"], "value": "hello"}]
+
+
+@pytest.mark.anyio
+async def test_empty_string_initial_write_emits_set() -> None:
+    """First write to a field initialized to "" should emit set, not append-text."""
+    ops: list[dict[str, Any]] = []
+    manager = StateManager(
+        lambda chunk: ops.extend(chunk.operations),
+        {"messages": [{"text": ""}]},
+    )
+
+    manager.state["messages"][0]["text"] = "Hello"
+    manager.flush()
+
+    assert ops == [{"type": "set", "path": ["messages", "0", "text"], "value": "Hello"}]
+
+
+@pytest.mark.anyio
+async def test_run_controller_append_state_text() -> None:
+    """RunController.append_state_text() should emit append-text operations."""
+
+    async def run_callback(controller: RunController):
+        controller.append_state_text(["user", "name"], "Al")
+        controller.append_state_text(["user", "name"], "ice")
+
+    chunks = [
+        chunk
+        async for chunk in create_run(
+            run_callback, state={"user": {"name": ""}}
+        )
+    ]
+    operations = [
+        operation
+        for chunk in chunks
+        if chunk.type == "update-state"
+        for operation in chunk.operations
+    ]
+
+    assert operations == [
+        {"type": "append-text", "path": ["user", "name"], "value": "Al"},
+        {"type": "append-text", "path": ["user", "name"], "value": "ice"},
+    ]