Save max fee rate in receiver session context

[arminsabouri]

The reference implementation currently overrides the original max fee rate preference when resuming a session. This commit pins the max fee rate preference to the session by persisting it in the session context. When applying fees, if the applications’s fee rate preference has changed, the updated preference takes precedence.

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Closes http://github.com/payjoin/rust-payjoin/issues/897
Changes were picked off #934

cc @Johnosezele

[coveralls]

Pull Request Test Coverage Report for Build 17436370745

Details

• 30 of 30 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.04%) to 85.946%

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Totals
Change from base Build 17413958316:	0.04%
Covered Lines:	8201
Relevant Lines:	9542

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💛 - Coveralls

[Johnosezele]

Thanks @arminsabouri
cACK 4b468f8

[DanGould]

"Co-authored-by" is the syntax you want in a commit message

[arminsabouri]

Dart tests are problematic

00:00 +0 -1: loading test/test_payjoin_integration_test.dart [E]
  Failed to load "test/test_payjoin_integration_test.dart":
  lib/payjoin_ffi.dart:4902:13: Error: The argument type 'FeeRateExceptionErrorHandler' can't be assigned to the parameter type 'UniffiRustCallStatusErrorHandler?'.
   - 'FeeRateExceptionErrorHandler' is from 'lib/bitcoin.dart'.
   - 'UniffiRustCallStatusErrorHandler' is from 'lib/payjoin_ffi.dart'.
          )), feeRateExceptionErrorHandler);

[spacebear21]

ACK c1c79df.

I think the spooky uniffi-dart error in CI is due to the return type in with_max_fee_rate containing bitcoin_ffi::error::FeeRateError.

[arminsabouri]

ACK c1c79df.

I think the spooky uniffi-dart error in CI is due to the return type in with_max_fee_rate containing bitcoin_ffi::error::FeeRateError.

Ended up wrapping bitcoin_ffi::error::FeeRateError in an internal error

[spacebear21]

ACK, opened an issue here to track the underlying uniffi-dart issue.