mirror of
https://github.com/rust-lang/rust-clippy
synced 2024-11-28 07:30:57 +00:00
d647696c1f
So, some context for this, well, more a story. I'm not used to scripting, I've never really scripted anything, even if it's a valuable skill. I just never really needed it. Now, `@flip1995` correctly suggested using a script for this in `rust-clippy#7813`...
And I decided to write a script using nushell because why not? This was a mistake... I spend way more time on this than I would like to admit. It has definitely been more than 4 hours. It shouldn't take that long, but me being new to scripting and nushell just wasn't a good mixture... Anyway, here is the script that creates another script which adds the versions. Fun...
Just execute this on the `gh-pages` branch and the resulting `replacer.sh` in `clippy_lints` and it should all work.
```nu
mv v0.0.212 rust-1.00.0;
mv beta rust-1.57.0;
mv master rust-1.58.0;
let paths = (open ./rust-1.58.0/lints.json | select id id_span | flatten | select id path);
let versions = (
ls | where name =~ "rust-" | select name | format {name}/lints.json |
each { open $it | select id | insert version $it | str substring "5,11" version} |
group-by id | rotate counter-clockwise id version |
update version {get version | first 1} | flatten | select id version);
$paths | each { |row|
let version = ($versions | where id == ($row.id) | format {version})
let idu = ($row.id | str upcase)
$"sed -i '0,/($idu),/{s/pub ($idu),/#[clippy::version = "($version)"]\n pub ($idu),/}' ($row.path)"
} | str collect ";" | str find-replace --all '1.00.0' 'pre 1.29.0' | save "replacer.sh";
```
And this still has some problems, but at this point I just want to be done -.-
87 lines
2.9 KiB
Rust
87 lines
2.9 KiB
Rust
use clippy_utils::diagnostics::span_lint_and_help;
|
|
use rustc_hir::intravisit::{walk_expr, walk_fn, FnKind, NestedVisitorMap, Visitor};
|
|
use rustc_hir::{Body, Expr, ExprKind, FnDecl, FnHeader, HirId, IsAsync, YieldSource};
|
|
use rustc_lint::{LateContext, LateLintPass};
|
|
use rustc_middle::hir::map::Map;
|
|
use rustc_session::{declare_lint_pass, declare_tool_lint};
|
|
use rustc_span::Span;
|
|
|
|
declare_clippy_lint! {
|
|
/// ### What it does
|
|
/// Checks for functions that are declared `async` but have no `.await`s inside of them.
|
|
///
|
|
/// ### Why is this bad?
|
|
/// Async functions with no async code create overhead, both mentally and computationally.
|
|
/// Callers of async methods either need to be calling from an async function themselves or run it on an executor, both of which
|
|
/// causes runtime overhead and hassle for the caller.
|
|
///
|
|
/// ### Example
|
|
/// ```rust
|
|
/// // Bad
|
|
/// async fn get_random_number() -> i64 {
|
|
/// 4 // Chosen by fair dice roll. Guaranteed to be random.
|
|
/// }
|
|
/// let number_future = get_random_number();
|
|
///
|
|
/// // Good
|
|
/// fn get_random_number_improved() -> i64 {
|
|
/// 4 // Chosen by fair dice roll. Guaranteed to be random.
|
|
/// }
|
|
/// let number_future = async { get_random_number_improved() };
|
|
/// ```
|
|
#[clippy::version = "1.54.0"]
|
|
pub UNUSED_ASYNC,
|
|
pedantic,
|
|
"finds async functions with no await statements"
|
|
}
|
|
|
|
declare_lint_pass!(UnusedAsync => [UNUSED_ASYNC]);
|
|
|
|
struct AsyncFnVisitor<'a, 'tcx> {
|
|
cx: &'a LateContext<'tcx>,
|
|
found_await: bool,
|
|
}
|
|
|
|
impl<'a, 'tcx> Visitor<'tcx> for AsyncFnVisitor<'a, 'tcx> {
|
|
type Map = Map<'tcx>;
|
|
|
|
fn visit_expr(&mut self, ex: &'tcx Expr<'tcx>) {
|
|
if let ExprKind::Yield(_, YieldSource::Await { .. }) = ex.kind {
|
|
self.found_await = true;
|
|
}
|
|
walk_expr(self, ex);
|
|
}
|
|
|
|
fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
|
|
NestedVisitorMap::OnlyBodies(self.cx.tcx.hir())
|
|
}
|
|
}
|
|
|
|
impl<'tcx> LateLintPass<'tcx> for UnusedAsync {
|
|
fn check_fn(
|
|
&mut self,
|
|
cx: &LateContext<'tcx>,
|
|
fn_kind: FnKind<'tcx>,
|
|
fn_decl: &'tcx FnDecl<'tcx>,
|
|
body: &Body<'tcx>,
|
|
span: Span,
|
|
hir_id: HirId,
|
|
) {
|
|
if let FnKind::ItemFn(_, _, FnHeader { asyncness, .. }, _) = &fn_kind {
|
|
if matches!(asyncness, IsAsync::Async) {
|
|
let mut visitor = AsyncFnVisitor { cx, found_await: false };
|
|
walk_fn(&mut visitor, fn_kind, fn_decl, body.id(), span, hir_id);
|
|
if !visitor.found_await {
|
|
span_lint_and_help(
|
|
cx,
|
|
UNUSED_ASYNC,
|
|
span,
|
|
"unused `async` for function with no await statements",
|
|
None,
|
|
"consider removing the `async` from this function",
|
|
);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|