@copilot a solution that requires every command to remember to call some method is not workable - instead you should use theAction of the common verbosity option to carry this 'set the env var logic'. You can give an Option anAction that System.CommandLine will call during invocation of the parsed command if that Option is part of the result set.

Doing this keeps the behavior consistent across all commands that use the verbosity.

@copilot a solution that requires every command to remember to call some method is not workable - instead you should use theAction of the common verbosity option to carry this 'set the env var logi...

I've refactored the implementation to use the Option Action pattern as you suggested. The ApplyVerbosityAction is now attached to all VerbosityOption definitions in CommonOptions, and all the per-command calls have been reverted (commit47b9106).

However, I'm finding that the Action doesn't appear to be invoked during testing. Could you clarify when System.CommandLine invokes Option Actions? Is there something specific I need to do to ensure the Action is called when the option is parsed?

@copilot the 'pre-actions' are collected during parsinghere, and then invoked sequentially during command invocationhere.

your implementation of the action needs to change slightly - you don't need to do all of this work to get the verbosity, you can just directly fetch the value from the parse result. If the action is being invoked you canassume that the verbosity is in the parse result. if you pass a reference to the verbosity option to the Action, then you can do something likeif (parseResult.GetValue(verbosityOption).IsDiagnostic()) { ... }

@copilot the 'pre-actions' are collected during parsinghere, and then invoked seq...

Updated the implementation to pass the option reference to the Action as you suggested (commite7a82e7). The Action now usesparseResult.GetValue(verbosityOption) directly instead of searching through all children. Made the Action generic to handle bothVerbosityOptions andVerbosityOptions? types. Verified working withdotnet build -v diag anddotnet restore -v diagnostic.