Rollup of 5 pull requests by GuillaumeGomez · Pull Request #126824 · rust-lang/rust (original) (raw)

…nur-ozkan

Bootstrap command refactoring: refactor BootstrapCommand (step 1)

This PR is a first step towards https://rust-lang.zulipchat.com/#narrow/stream/326414-t-infra.2Fbootstrap.

It refactors BoostrapCommand to get it closer to a state where it is an actual command wrapper that can be routed through a central place of command execution, and also to make the distinction between printing output vs handling output programatically clearer (since now it's a mess).

The existing usages of BootstrapCommand are complicated primarily because of different ways of handling output. There are commands that:

1. Want to eagerly print stdout/stderr of the executed command, plus print an error message if the command fails (output mode PrintAll). Note that this error message attempts to print stdout/stderr of the command when -v is enabled, but that will always be empty, since this mode uses .status() and not .output().
2. Want to eagerly print stdout/stderr of the executed command, but do not print any additional error message if it fails (output mode PrintOutput)
3. Want to capture stdout/stderr of the executed command, but print an error message if it fails (output mode PrintFailure). This means that the user wants to either ignore the output or handle it programatically, but that's not obvious from the name.

The difference between 1) and 2) (unless explicitly specified) is determined dynamically based on the bootstrap verbosity level.

It is very difficult for me to wrap my head around all these modes. I think that in a future PR, we should split these axes into e.g. this:

1. Do I want to handle the output programmatically or print it to the terminal? This should be a separate axis, true/false. (Note that "hiding the output" essentially just means saying that I handle it programmatically, and then I ignore the output).
2. Do I want to print a message if the command fails? Yes/No/Based on verbosity (which would be the default).

Then there is also the failure mode, but that is relatively simple to handle, the command execution will just shutdown bootstrap (either eagerly or late) when the command fails.

Note that this is just a first refactoring steps, there are a lot of other things to be done, so some things might not look "final" yet. The next steps are (not necessarily in this order):

• Remove run and run_cmd and implement everything in terms of run_tracked and rename run_tracked to run
• Implement the refactoring specified above (change how output modes work)
• Modify BootstrapCmd so that it stores Command instead of &mut Command and remove all the annoying BootstrapCmd::from by changing Command::new to BootstrapCmd::new
• Refactor the rest of command executions not currently using BootstrapCmd that can access Builder to use the correct output and failure modes. This will include passing Builder to additional places.
• Handle the most complex cases, such as output streaming. That will probably need to be handled separately.
• Refactor the rest of commands that cannot access builder (e.g. Config::parse) by introducing a new command context that will be passed to these places, and then stored in Builder. Move certain fields (such as fail_fast) from Builder to the command context.
• Handle the co-operation of Builder, Build, Config and command context. There are some fields and logic used during command execution that are distributed amongst Builder/Build/Config, so it will require some refactoring to make it work if the execution will happen on a separate place (in the command context).
• Refactor logging of commands, so that it is either logged to a file or printed in a nice hierarchical way that cooperates with the Step debug hierarchical output.
• Implement profiling of commands (add command durations to the command log, print a log of slowest commands and their execution counts at the end of bootstrap execution, perhaps store command executions to metrics.json).
• Implement caching of commands.
• Implement testing of commands through snapshot tests/mocking.

Best reviewed commit by commit.

r? @onur-ozkan