`on-runtime-upgrade` does not run neither `pre_upgrade` nor `post_upgrade` without `--disable-mbm-checks`

[bkontur]

Neither of the following examples runs those hooks:
--checks=pre-and-post

try-runtime --runtime ./target/release/wbuild/bridge-hub-westend-runtime/bridge_hub_westend_runtime.compact.compressed.wasm on-runtime-upgrade --disable-spec-version-check --checks=pre-and-post --blocktime 6000 live --uri wss://westend-bridge-hub-rpc.polkadot.io

nor --checks=all

try-runtime --runtime ./target/release/wbuild/bridge-hub-westend-runtime/bridge_hub_westend_runtime.compact.compressed.wasm on-runtime-upgrade --disable-spec-version-check --checks=all --blocktime 6000 live --uri wss://westend-bridge-hub-rpc.polkadot.io

The pre_upgrade nor post_upgrade hooks are only triggered when I add --disable-mbm-checks. It could mean that for MBM migrations we don't check pre_upgrade / post_upgrade - maybe intentional?

But the consequence is that e.g. for polkadot-fellows we just run pre_upgrade / post_upgrade only for Encointer see: https://github.com/polkadot-fellows/runtimes/blob/main/.github/workflows/runtimes-matrix.json#L104.

I think it could be related to the https://github.com/paritytech/try-runtime-cli/blob/main/core/src/commands/on_runtime_upgrade/mod.rs#L135-L139

        let sync_checks = if command.disable_mbm_checks {
            command.checks
        } else {
            UpgradeCheckSelect::None
        };

[ggwpez]

Hm, looks like the flag should be swapped. Weird since i though there are tests for this 😓

I assume there were cases that there is a single-block and a multi-block migration for some part of the state and the single-block post checks would faill before the MBM ran, but there are ways to fix this. Not sure what my thinking here was.

[bkontur]

I assume there were cases that there is a single-block and a multi-block migration for some part of the state and the single-block post checks would faill before the MBM ran, but there are ways to fix this.

yes, that could be it, for polkadot-fellows we don't use MBM yet, but for polkadot-sdk testnets we do