Refactors tests folder to separate different modules

Each module has a different folder and they do not share methods now. At some point they should be split in different repos

test/pisa/unit/test_carrier.py

@@ -0,0 +1,74 @@
+import pytest
+
+from pisa import c_logger
+from pisa.carrier import Carrier
+from test.simulator.utils import sha256d
+from test.simulator.transaction import TX
+from test.pisa.unit.conftest import generate_blocks, get_random_value_hex
+from pisa.rpc_errors import RPC_VERIFY_ALREADY_IN_CHAIN, RPC_DESERIALIZATION_ERROR
+
+c_logger.disabled = True
+
+# FIXME: This test do not fully cover the carrier since the simulator does not support every single error bitcoind may
+#        return for RPC_VERIFY_REJECTED and RPC_VERIFY_ERROR. Further development of the simulator / mocks or simulation
+#        with bitcoind is required
+
+
+sent_txs = []
+
+
+@pytest.fixture(scope="module")
+def carrier():
+    return Carrier()
+
+
+def test_send_transaction(run_bitcoind, carrier):
+    tx = TX.create_dummy_transaction()
+    txid = sha256d(tx)
+
+    receipt = carrier.send_transaction(tx, txid)
+
+    assert receipt.delivered is True
+
+
+def test_send_double_spending_transaction(carrier):
+    # We can test what happens if the same transaction is sent twice
+    tx = TX.create_dummy_transaction()
+    txid = sha256d(tx)
+
+    receipt = carrier.send_transaction(tx, txid)
+    sent_txs.append(txid)
+
+    # Wait for a block to be mined
+    generate_blocks(2)
+
+    # Try to send it again
+    receipt2 = carrier.send_transaction(tx, txid)
+
+    # The carrier should report delivered True for both, but in the second case the transaction was already delivered
+    # (either by himself or someone else)
+    assert receipt.delivered is True
+    assert receipt2.delivered is True and receipt2.confirmations >= 1 and receipt2.reason == RPC_VERIFY_ALREADY_IN_CHAIN
+
+
+def test_send_transaction_invalid_format(carrier):
+    # Test sending a transaction that does not fits the format
+    tx = TX.create_dummy_transaction()
+    txid = sha256d(tx)
+    receipt = carrier.send_transaction(txid, txid)
+
+    assert receipt.delivered is False and receipt.reason == RPC_DESERIALIZATION_ERROR
+
+
+def test_get_transaction():
+    # We should be able to get back every transaction we've sent
+    for tx in sent_txs:
+        tx_info = Carrier.get_transaction(tx)
+
+        assert tx_info is not None
+
+
+def test_get_non_existing_transaction():
+    tx_info = Carrier.get_transaction(get_random_value_hex(32))
+
+    assert tx_info is None