bundle2-localpeer: properly propagate the server output on error (issue4594) In case of errors, output parts salvaged from the reply bundle need to be processed for outputting their content. This concludes our quest for fixing issue4594.

bundle2: add on more layer of exception catching in localrepo.unbundle We are going to add output related logic in this function. We do the indentation first to help next changeset readability. We need a new try except because we want to handle output on any exception, including PushRaced ones.

bundle2-wireproto: properly propagate the server output on error (issue4594) In case of errors, output parts salvaged from the reply bundle are re-injected into the bundle carrying the exception. We still need to fix the situation for non-wireprotocol push.

bundle2: refactor error bundle creation for the wireprotocol We want to add output information to the error bundle. Before doing this, we rework the code to have a single bundler creation and return statement. This will make the update with the output simpler as only one place will have to be touched.

bundle2: store the salvaged output on the exception object The re-handling of output is happening in some 'unbundle' callers. We have to transmit the output information to this place so we stick it on the exception. This is the third step in our quest for preserving the server output on error (issue4594). We want to be able to copy the output part from the aborted reply into the exception bundle.

bundle2: add a 'salvageoutput' method on bundle20 This method returns a copy of all 'output' parts added to the bundler. This is the second step in our quest for preserving the server output on error (issue4594). We want to be able to copy the output parts from the aborted reply into the exception bundle. The function will be used in a later patch.

bundle2: add a 'copy' method on parts This is the first step in our quest for preserving the server output on error (issue4594). We want to be able to copy the output parts from the aborted reply into the exception bundle. The function will be used in a later patch.

hooks: add a 'txnabort' hook This hook will be called whenever a transaction is aborted. This will make it easy for people to clean up temporary content they may have created during a transaction.