Improved unit test coverage for TransactionId class.

Signed-off-by: Adityarya11 <[email protected]>

Author: Adityarya11

CHANGELOG.md

@@ -81,6 +81,7 @@ This changelog is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.
 - Added merge conflict bot workflow (`.github/workflows/bot-merge-conflict.yml`) and helper script (`.github/scripts/bot-merge-conflict.js`) to detect and notify about PR merge conflicts, with retry logic for unknown mergeable states, idempotent commenting, and push-to-main recheck logic (#1247)
 - Added workflow to prevent assigning intermediate issues to contributors without prior Good First Issue completion (#1143).
 - Added `Client.from_env()` and network-specific factory methods (e.g., `Client.for_testnet()`) to simplify client initialization and reduce boilerplate. [[#1251](https://github.com/hiero-ledger/hiero-sdk-python/issues/1251)]
+- Improved unit test coverage for `TransactionId` class, covering parsing logic, hashing, and scheduled transactions.
 
 ### Changed
 

tests/unit/transaction_id_test.py

@@ -0,0 +1,75 @@
+import pytest
+from hiero_sdk_python import (
+    TransactionId, 
+    AccountId
+)
+
+def test_from_string_valid():
+        """Test parsing a valid transaction ID string."""
+        tx_id_str = "[email protected]"
+        tx_id = TransactionId.from_string(tx_id_str)
+        
+        assert tx_id.account_id == AccountId(0, 0, 123)
+        assert tx_id.valid_start.seconds == 1234567890
+        assert tx_id.valid_start.nanos == 123456789
+        assert tx_id.scheduled is False
+
+def test_from_string_invalid_format_raises_error():
+    """Test that invalid formats raise ValueError (covers the try-except block)."""
+    invalid_strings = [
+        "invalid_string",
+        "0.0.123.123456789",  # Missing @ separator
+        "0.0.123@12345",      # Missing . in timestamp
+        "[email protected]",    # Non-numeric timestamp
+    ]
+    
+    for s in invalid_strings:
+        with pytest.raises(ValueError) as exc_info:
+            TransactionId.from_string(s)
+        assert f"Invalid TransactionId string format: {s}" in str(exc_info.value)
+
+def test_hash_implementation():
+    """Test __hash__ implementation coverage."""
+    tx_id1 = TransactionId.from_string("[email protected]")
+    tx_id2 = TransactionId.from_string("[email protected]")
+    tx_id3 = TransactionId.from_string("[email protected]")
+    
+    # Hashes should be equal for equal objects
+    assert hash(tx_id1) == hash(tx_id2)
+    # Hashes should typically differ for different objects
+    assert hash(tx_id1) != hash(tx_id3)
+    
+    # Verify usage in sets
+    unique_ids = {tx_id1, tx_id2, tx_id3}
+    assert len(unique_ids) == 2
+
+def test_equality():
+    """Test __eq__ implementation."""
+    tx_id1 = TransactionId.from_string("[email protected]")
+    tx_id2 = TransactionId.from_string("[email protected]")
+    
+    assert tx_id1 == tx_id2
+    assert tx_id1 != "some_string"
+    assert tx_id1 != TransactionId.from_string("[email protected]")
+
+def test_to_proto_sets_scheduled():
+    """Test that _to_proto sets the scheduled flag correctly."""
+    tx_id = TransactionId.from_string("[email protected]")
+    
+    # Default is False
+    proto_default = tx_id._to_proto()
+    assert proto_default.scheduled is False
+    
+    # Set to True
+    tx_id.scheduled = True
+    proto_scheduled = tx_id._to_proto()
+    assert proto_scheduled.scheduled is True
+
+def test_generate():
+    """Test generating a new TransactionId."""
+    account_id = AccountId(0, 0, 123)
+    tx_id = TransactionId.generate(account_id)
+    
+    assert tx_id.account_id == account_id
+    assert tx_id.valid_start is not None
+    assert tx_id.valid_start.seconds > 0