[Application Development] L1 tx fee no longer correctly estimated using l1_gas * gasOracle.l1BaseFee

[deanpress]

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Issue Description

Previously, smart contracts were able to estimate their own L1 fee paid by querying the GasOracle and multiplying the l1BaseFee value by the L1 gas estimation.

However, since Dencun, this is no longer the case. The docs still describe this same calculation for estimating the gas fee, but the real L1 fee paid is now much lower than this calculation.

Is there any way we can still estimate the L1 gas fee by querying the GasOracle contract?

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[deanpress]

Found here that you now need to compress the tx data by calculating the following:

1. tx_compressed_size = [(count_zero_bytes(tx_data)*4 + count_non_zero_bytes(tx_data)*16)] / 16
2. weighted_gas_price = 16*base_fee_scalar*base_fee + blob_base_fee_scalar*blob_base_fee
3. l1_data_fee = tx_compressed_size * weighted_gas_price