diff options
Diffstat (limited to 'accounts/abi/bind/backends/simulated.go')
| -rw-r--r-- | accounts/abi/bind/backends/simulated.go | 28 |
1 files changed, 25 insertions, 3 deletions
diff --git a/accounts/abi/bind/backends/simulated.go b/accounts/abi/bind/backends/simulated.go index c26662ea1..1c34ba0e7 100644 --- a/accounts/abi/bind/backends/simulated.go +++ b/accounts/abi/bind/backends/simulated.go @@ -201,10 +201,32 @@ func (b *SimulatedBackend) SuggestGasPrice(ctx context.Context) (*big.Int, error func (b *SimulatedBackend) EstimateGas(ctx context.Context, call ethereum.CallMsg) (*big.Int, error) { b.mu.Lock() defer b.mu.Unlock() - defer b.pendingState.RevertToSnapshot(b.pendingState.Snapshot()) - _, gas, err := b.callContract(ctx, call, b.pendingBlock, b.pendingState) - return gas, err + // Binary search the gas requirement, as it may be higher than the amount used + var lo, hi uint64 + if call.Gas != nil { + hi = call.Gas.Uint64() + } else { + hi = b.pendingBlock.GasLimit().Uint64() + } + for lo+1 < hi { + // Take a guess at the gas, and check transaction validity + mid := (hi + lo) / 2 + call.Gas = new(big.Int).SetUint64(mid) + + snapshot := b.pendingState.Snapshot() + _, gas, err := b.callContract(ctx, call, b.pendingBlock, b.pendingState) + b.pendingState.RevertToSnapshot(snapshot) + + // If the transaction became invalid or used all the gas (failed), raise the gas limit + if err != nil || gas.Cmp(call.Gas) == 0 { + lo = mid + continue + } + // Otherwise assume the transaction succeeded, lower the gas limit + hi = mid + } + return new(big.Int).SetUint64(hi), nil } // callContract implemens common code between normal and pending contract calls. |