./x test --help --verbose is not very discoverable and may produce excess output (consider adding --list)

Summary

This command lists all the different test targets that exist, however it is not very easy to find this behavior since it is not listed in the normal helptext.

Additionally, this command causes cargo to be run in verbose mode, which causes a lot of usually not interesting info to be printed.

Command used

./x test --help
./x test --help --verbose

Expected behaviour

Somewhere in the regular helptext this functionality is listed, or there is a --list flag that does a similar thing but doesn't run cargo in verbose mode (additionally, a --list flag could accept an argument and only print paths matching that argument).

Actual behaviour

Nothing printed by ./x test --help says how to get a list of test paths.

Bootstrap configuration (bootstrap.toml)

profile = "tools"  # Includes one of the default files in src/bootstrap/defaults
change-id = 138986

Operating system

Arch Linux (rolling)

HEAD

02257c202b33054a623bed712efe7f887b482a02

Start by comparing the output of ./x test --help and ./x test --help --verbose, then trace the bootstrap test command's help implementation. Done means the normal help explains how to list test paths, or a --list option provides that behavior without unnecessary verbose Cargo output and optionally filters paths.