cross check next fee

tests/integration_tests/test_fee_history.py

@@ -90,3 +90,39 @@ def test_change(cluster):
  assert history1 != history0
  else:
  assert history1 == history0
+
+
+def adjust_base_fee(parent_fee, gas_limit, gas_used):
+ "spec: https://eips.ethereum.org/EIPS/eip-1559#specification"
+ change_denominator = 8
+ elasticity_multiplier = 2
+ gas_target = gas_limit // elasticity_multiplier
+ delta = parent_fee * (gas_target - gas_used) // gas_target // change_denominator
+ return parent_fee - delta
+
+
+def test_next(cluster):
+ w3: Web3 = cluster.w3
+ call = w3.provider.make_request
+ tx = {"to": ADDRS["community"], "value": 10, "gasPrice": w3.eth.gas_price}
+ send_transaction(w3, tx)
+ method = "eth_feeHistory"
+ field = "baseFeePerGas"
+ percentiles = [100]
+ blocks = []
+ histories = []
+ for _ in range(3):
+ b = w3.eth.block_number
+ blocks.append(b)
+ histories.append(tuple(call(method, [1, hex(b), percentiles])["result"][field]))
+ w3_wait_for_new_blocks(w3, 1, 0.1)
+ blocks.append(w3.eth.block_number)
+ expected = []
+ for b in blocks:
+ next_base_price = w3.eth.get_block(b).baseFeePerGas
+ blk = w3.eth.get_block(b - 1)
+ assert next_base_price == adjust_base_fee(
+ blk.baseFeePerGas, blk.gasLimit, blk.gasUsed
+ )
+ expected.append(hex(next_base_price))
+ assert histories == list(zip(expected, expected[1:]))