test two_trades_cancel

lib/agent0/agent0/hyperdrive/interactive/interactive_hyperdrive_test.py

@@ -17,6 +17,8 @@
 # pylint: disable=redefined-outer-name
 # ruff: noqa: PLR2004 (comparison against magic values (literals like numbers))
 
+YEAR_IN_SECONDS = 31_536_000
+
 
 @pytest.mark.anvil
 def _ensure_db_wallet_matches_agent_wallet(
@@ -592,3 +594,25 @@ def test_policy_config_forgotten(chain: LocalChain):
         policy=Zoo.random,
     )
     assert alice.agent.policy is not None
+
+
+@pytest.mark.anvil
+def test_two_trades_cancel(chain: LocalChain):
+    """The economic impact of two trades on the same number of bonds, but in opposite directions, should cancel."""
+    initial_liquidity = FixedPoint(10_000_000)
+    interactive_config = InteractiveHyperdrive.Config(
+        position_duration=YEAR_IN_SECONDS, governance_lp_fee=FixedPoint(0), initial_liquidity=initial_liquidity
+    )
+    interactive_hyperdrive = InteractiveHyperdrive(chain, interactive_config)
+    starting_fixed_rate = interactive_hyperdrive.hyperdrive_interface.calc_fixed_rate()
+    # give them same amount of base as in the pool, so they can trade whatever they want
+    alice = interactive_hyperdrive.init_agent(base=initial_liquidity)
+    bob = interactive_hyperdrive.init_agent(base=initial_liquidity)
+    event = alice.open_long(base=FixedPoint(1e6))  # trade 1 million in a pool with 10 million liquidity
+    bob.open_short(bonds=event.bond_amount)
+    ending_fixed_rate = interactive_hyperdrive.hyperdrive_interface.calc_fixed_rate()
+    assert ending_fixed_rate == starting_fixed_rate, (
+        f"Expected {starting_fixed_rate} but got {ending_fixed_rate}"
+        f", diff={ending_fixed_rate - starting_fixed_rate}"
+        f", diff(%)={Decimal(str((ending_fixed_rate - starting_fixed_rate) / starting_fixed_rate)):e}"
+    )