test(tck): add unit tests for appendFile handler; drop redundant comment

Cover parse_json_params validation, setter wiring/order, common-params
application, and receipt/precheck error propagation for the appendFile
TCK handler.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012pHMCjruc9zs24St46vPDx
Signed-off-by: tannaya7 <234580934+tannaya7@users.noreply.github.com>

Author: tannaya7

tck/handlers/file.py

@@ -69,7 +69,6 @@ def _build_append_file_transaction(params: AppendFileParams) -> FileAppendTransa
     # INVALID_FILE_ID rather than raising a client-side ValueError (TCK FileId #5).
     transaction.set_file_id(FileId.from_string(params.fileId) if params.fileId is not None else FileId())
 
-    # chunk count is derived from contents/chunk_size, so set those before max_chunks
     if params.contents is not None:
         transaction.set_contents(params.contents)
 

tests/tck/file_test.py

@@ -0,0 +1,151 @@
+"""Test cases for the appendFile TCK handler and its parameter parsing."""
+
+from __future__ import annotations
+
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+from hiero_sdk_python.exceptions import PrecheckError, ReceiptStatusError
+from hiero_sdk_python.response_code import ResponseCode
+from tck.handlers import registry
+from tck.handlers.file import append_file
+from tck.param.file import AppendFileParams
+from tck.response.base import StatusOnlyResponse
+
+
+pytestmark = pytest.mark.unit
+
+
+def _mock_transaction():
+    """A MagicMock standing in for FileAppendTransaction's fluent setter chain."""
+    tx = MagicMock()
+    tx.set_grpc_deadline.return_value = tx
+    tx.set_file_id.return_value = tx
+    tx.set_contents.return_value = tx
+    tx.set_chunk_size.return_value = tx
+    tx.set_max_chunks.return_value = tx
+
+    receipt = MagicMock(status=ResponseCode.SUCCESS)
+    tx.execute.return_value.get_receipt.return_value = receipt
+    return tx
+
+
+def test_append_file_is_registered():
+    handler = registry.get_handler("appendFile")
+    assert handler is not None and callable(handler)
+
+
+def test_parse_json_params():
+    """Only contents is required; maxChunks/chunkSize go through to_int."""
+    params = AppendFileParams.parse_json_params(
+        {
+            "sessionId": "session-1",
+            "fileId": "0.0.100",
+            "contents": "hello world",
+            "maxChunks": "5",
+            "chunkSize": "1024",
+        }
+    )
+
+    assert params.fileId == "0.0.100"
+    assert params.contents == "hello world"
+    assert params.maxChunks == 5
+    assert params.chunkSize == 1024
+
+    minimal = AppendFileParams.parse_json_params({"sessionId": "session-1", "contents": "hello"})
+    assert minimal.fileId is None
+    assert minimal.maxChunks is None
+    assert minimal.chunkSize is None
+
+
+def test_parse_json_params_requires_contents():
+    """contents is spec-required; missing or non-string values must fail fast, not build an empty append."""
+    with pytest.raises(ValueError):
+        AppendFileParams.parse_json_params({"sessionId": "session-1"})
+
+    with pytest.raises(ValueError):
+        AppendFileParams.parse_json_params({"sessionId": "session-1", "contents": 123})
+
+
+def test_append_file_wires_setters_and_returns_status():
+    """contents/chunkSize must land before maxChunks, since chunk count derives from them."""
+    params = AppendFileParams(
+        sessionId="session-1", fileId="0.0.100", contents="hello world", maxChunks=5, chunkSize=1024
+    )
+    tx = _mock_transaction()
+
+    with (
+        patch("tck.handlers.file.get_client", return_value=MagicMock()),
+        patch("tck.handlers.file.FileAppendTransaction", return_value=tx),
+    ):
+        result = append_file(params)
+
+    assert isinstance(result, StatusOnlyResponse)
+    assert result.status == "SUCCESS"
+
+    tx.set_file_id.assert_called_once()
+    tx.set_contents.assert_called_once_with("hello world")
+    tx.set_chunk_size.assert_called_once_with(1024)
+    tx.set_max_chunks.assert_called_once_with(5)
+
+    setter_order = [call[0] for call in tx.method_calls if call[0].startswith("set_")]
+    assert setter_order.index("set_contents") < setter_order.index("set_max_chunks")
+    assert setter_order.index("set_chunk_size") < setter_order.index("set_max_chunks")
+
+
+def test_append_file_applies_common_transaction_params():
+    """commonTransactionParams.signers has to reach freeze/sign via apply_common_params."""
+    common_params = MagicMock()
+    params = AppendFileParams(sessionId="session-1", contents="hello", commonTransactionParams=common_params)
+    tx = _mock_transaction()
+    client = MagicMock()
+
+    with (
+        patch("tck.handlers.file.get_client", return_value=client),
+        patch("tck.handlers.file.FileAppendTransaction", return_value=tx),
+    ):
+        append_file(params)
+
+    common_params.apply_common_params.assert_called_once_with(tx, client)
+
+
+def test_append_file_propagates_receipt_failure():
+    """A bad receipt status (e.g. non-existent file -> INVALID_FILE_ID) should raise, not be swallowed."""
+    params = AppendFileParams(sessionId="session-1", fileId="0.0.999999", contents="hello")
+    tx = _mock_transaction()
+    tx.execute.return_value.get_receipt.side_effect = ReceiptStatusError(
+        status=ResponseCode.INVALID_FILE_ID,
+        transaction_id=None,
+        transaction_receipt=MagicMock(),
+        message="INVALID_FILE_ID",
+    )
+
+    with (
+        patch("tck.handlers.file.get_client", return_value=MagicMock()),
+        patch("tck.handlers.file.FileAppendTransaction", return_value=tx),
+        pytest.raises(ReceiptStatusError),
+    ):
+        append_file(params)
+
+
+def test_append_file_propagates_later_chunk_failure():
+    """A later chunk failing at submission must surface, not get masked by the first chunk's SUCCESS."""
+    params = AppendFileParams(sessionId="session-1", fileId="0.0.100", contents="x" * 10_000)
+    tx = _mock_transaction()
+    tx.execute.side_effect = PrecheckError(status=1, transaction_id="0.0.1@1.1", message="later chunk failed")
+
+    with (
+        patch("tck.handlers.file.get_client", return_value=MagicMock()),
+        patch("tck.handlers.file.FileAppendTransaction", return_value=tx),
+        pytest.raises(PrecheckError),
+    ):
+        append_file(params)
+
+
+def test_append_file_invalid_file_id_raises():
+    """A malformed fileId should fail via FileId.from_string before hitting the network."""
+    params = AppendFileParams(sessionId="session-1", fileId="not-a-file-id", contents="hello")
+
+    with patch("tck.handlers.file.get_client", return_value=MagicMock()), pytest.raises(ValueError):
+        append_file(params)