Module verify 

Verified CPI – pre/post state assertions around cross-program invocations.

Hopper can bind a CPI call to explicit post-conditions instead of treating a successful return code as proof of the application-level result.

The pattern: snapshot relevant state before CPI, invoke, then assert post-conditions. These helpers return an error on mismatch. Propagate that error to the instruction boundary (?) to roll back the transaction; catching or ignoring it does not undo the CPI. They do not grant transfer authority.

Usage

use hopper_native::verify::LamportSnapshot;

// Before CPI transfer:
let snap = LamportSnapshot::capture(source, destination);

// Do the CPI:
system_transfer(&source, &destination, amount)?;

// Verify the transfer actually happened correctly:
snap.verify_transfer(source, destination, amount)?;

This catches:

• Called program transferring wrong amount
• Called program not deducting from source
• Called program crediting wrong destination
• Integer overflow in lamport accounting

Structs

BalanceSnapshot

Snapshot of a single account’s lamports for simple balance assertions.

DataFingerprint

Fast integrity check for account data using FNV-1a hash.

LamportSnapshot

Snapshot of lamport balances for two accounts before a CPI.