make Step doc-comments more clear

Signed-off-by: onur-ozkan <work@onurozkan.dev>
This commit is contained in:
onur-ozkan 2024-09-28 10:59:17 +03:00
parent 76ed7a1fa4
commit 8ef0ba2225

View file

@ -72,36 +72,40 @@ impl<'a> Deref for Builder<'a> {
}
pub trait Step: 'static + Clone + Debug + PartialEq + Eq + Hash {
/// `PathBuf` when directories are created or to return a `Compiler` once
/// it's been assembled.
/// Result type of `Step::run`.
type Output: Clone;
/// Whether this step is run by default as part of its respective phase.
/// `true` here can still be overwritten by `should_run` calling `default_condition`.
/// Whether this step is run by default as part of its respective phase, as defined by the `describe`
/// macro in [`Builder::get_step_descriptions`].
///
/// Note: Even if set to `true`, it can still be overridden with [`ShouldRun::default_condition`]
/// by `Step::should_run`.
const DEFAULT: bool = false;
/// If true, then this rule should be skipped if --target was specified, but --host was not
const ONLY_HOSTS: bool = false;
/// Primary function to execute this rule. Can call `builder.ensure()`
/// with other steps to run those.
/// Primary function to implement `Step` logic.
///
/// This gets called twice during a normal `./x.py` execution: first
/// with `dry_run() == true`, and then for real.
/// This function can be triggered in two ways:
/// 1. Directly from [`Builder::execute_cli`].
/// 2. Indirectly by being called from other `Step`s using [`Builder::ensure`].
///
/// When called with [`Builder::execute_cli`] (as done by `Build::build`), this function executed twice:
/// - First in "dry-run" mode to validate certain things (like cyclic Step invocations,
/// directory creation, etc) super quickly.
/// - Then it's called again to run the actual, very expensive process.
///
/// When triggered indirectly from other `Step`s, it may still run twice (as dry-run and real mode)
/// depending on the `Step::run` implementation of the caller.
fn run(self, builder: &Builder<'_>) -> Self::Output;
/// When bootstrap is passed a set of paths, this controls whether this rule
/// will execute. However, it does not get called in a "default" context
/// when we are not passed any paths; in that case, `make_run` is called
/// directly.
/// Determines if this `Step` should be run when given specific paths (e.g., `x build $path`).
fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_>;
/// Builds up a "root" rule, either as a default rule or from a path passed
/// to us.
///
/// When path is `None`, we are executing in a context where no paths were
/// passed. When `./x.py build` is run, for example, this rule could get
/// called if it is in the correct list below with a path of `None`.
/// Called directly by the bootstrap `Step` handler when not triggered indirectly by other `Step`s using [`Builder::ensure`].
/// For example, `./x.py test bootstrap` runs this for `test::Bootstrap`. Similarly, `./x.py test` runs it for every step
/// that is listed by the `describe` macro in [`Builder::get_step_descriptions`].
fn make_run(_run: RunConfig<'_>) {
// It is reasonable to not have an implementation of make_run for rules
// who do not want to get called from the root context. This means that