2021-03-25 13:29:11 -05:00
|
|
|
use clippy_utils::diagnostics::{multispan_sugg, span_lint_and_then};
|
|
|
|
use clippy_utils::ptr::get_spans;
|
|
|
|
use clippy_utils::source::{snippet, snippet_opt};
|
2022-12-01 11:29:38 -06:00
|
|
|
use clippy_utils::ty::{
|
|
|
|
implements_trait, implements_trait_with_env, is_copy, is_type_diagnostic_item, is_type_lang_item,
|
|
|
|
};
|
2021-03-25 13:29:11 -05:00
|
|
|
use clippy_utils::{get_trait_def_id, is_self, paths};
|
2018-11-27 14:14:15 -06:00
|
|
|
use if_chain::if_chain;
|
2020-02-29 21:23:33 -06:00
|
|
|
use rustc_ast::ast::Attribute;
|
2022-01-23 14:41:46 -06:00
|
|
|
use rustc_errors::{Applicability, Diagnostic};
|
2020-01-09 01:13:22 -06:00
|
|
|
use rustc_hir::intravisit::FnKind;
|
2022-08-30 17:36:53 -05:00
|
|
|
use rustc_hir::{
|
|
|
|
BindingAnnotation, Body, FnDecl, GenericArg, HirId, Impl, ItemKind, Mutability, Node, PatKind, QPath, TyKind,
|
|
|
|
};
|
2023-07-02 07:35:19 -05:00
|
|
|
use rustc_hir::{HirIdSet, LangItem};
|
2022-10-20 10:51:48 -05:00
|
|
|
use rustc_hir_typeck::expr_use_visitor as euv;
|
2020-02-16 20:07:26 -06:00
|
|
|
use rustc_infer::infer::TyCtxtInferExt;
|
2020-01-12 00:08:41 -06:00
|
|
|
use rustc_lint::{LateContext, LateLintPass};
|
2021-02-25 14:33:18 -06:00
|
|
|
use rustc_middle::mir::FakeReadCause;
|
2023-02-21 20:18:40 -06:00
|
|
|
use rustc_middle::ty::{self, TypeVisitableExt};
|
2020-01-11 05:37:08 -06:00
|
|
|
use rustc_session::{declare_lint_pass, declare_tool_lint};
|
2023-01-22 12:00:33 -06:00
|
|
|
use rustc_span::def_id::LocalDefId;
|
2021-01-15 03:56:44 -06:00
|
|
|
use rustc_span::symbol::kw;
|
2022-10-27 09:32:17 -05:00
|
|
|
use rustc_span::{sym, Span};
|
2018-12-29 09:04:45 -06:00
|
|
|
use rustc_target::spec::abi::Abi;
|
2020-03-14 15:26:32 -05:00
|
|
|
use rustc_trait_selection::traits;
|
2022-11-30 14:41:02 -06:00
|
|
|
use rustc_trait_selection::traits::misc::type_allowed_to_implement_copy;
|
2017-02-18 02:00:36 -06:00
|
|
|
|
2018-03-28 08:24:26 -05:00
|
|
|
declare_clippy_lint! {
|
2021-07-29 05:16:06 -05:00
|
|
|
/// ### What it does
|
|
|
|
/// Checks for functions taking arguments by value, but not
|
2019-03-05 10:50:33 -06:00
|
|
|
/// consuming them in its
|
|
|
|
/// body.
|
|
|
|
///
|
2021-07-29 05:16:06 -05:00
|
|
|
/// ### Why is this bad?
|
|
|
|
/// Taking arguments by reference is more flexible and can
|
2019-03-05 10:50:33 -06:00
|
|
|
/// sometimes avoid
|
|
|
|
/// unnecessary allocations.
|
|
|
|
///
|
2021-07-29 05:16:06 -05:00
|
|
|
/// ### Known problems
|
2019-03-05 10:50:33 -06:00
|
|
|
/// * This lint suggests taking an argument by reference,
|
|
|
|
/// however sometimes it is better to let users decide the argument type
|
|
|
|
/// (by using `Borrow` trait, for example), depending on how the function is used.
|
|
|
|
///
|
2021-07-29 05:16:06 -05:00
|
|
|
/// ### Example
|
2019-03-05 10:50:33 -06:00
|
|
|
/// ```rust
|
|
|
|
/// fn foo(v: Vec<i32>) {
|
|
|
|
/// assert_eq!(v.len(), 42);
|
|
|
|
/// }
|
2019-08-03 11:42:05 -05:00
|
|
|
/// ```
|
2020-08-11 08:43:21 -05:00
|
|
|
/// should be
|
2019-08-03 11:42:05 -05:00
|
|
|
/// ```rust
|
2019-03-05 10:50:33 -06:00
|
|
|
/// fn foo(v: &[i32]) {
|
|
|
|
/// assert_eq!(v.len(), 42);
|
|
|
|
/// }
|
|
|
|
/// ```
|
2021-12-06 05:33:31 -06:00
|
|
|
#[clippy::version = "pre 1.29.0"]
|
2017-02-19 21:50:31 -06:00
|
|
|
pub NEEDLESS_PASS_BY_VALUE,
|
2018-11-21 03:58:27 -06:00
|
|
|
pedantic,
|
2017-02-19 21:50:31 -06:00
|
|
|
"functions taking arguments by value, but not consuming them in its body"
|
2017-02-18 02:00:36 -06:00
|
|
|
}
|
|
|
|
|
2019-04-08 15:43:55 -05:00
|
|
|
declare_lint_pass!(NeedlessPassByValue => [NEEDLESS_PASS_BY_VALUE]);
|
2017-02-18 02:00:36 -06:00
|
|
|
|
2017-03-16 02:57:17 -05:00
|
|
|
macro_rules! need {
|
2018-11-27 14:14:15 -06:00
|
|
|
($e: expr) => {
|
|
|
|
if let Some(x) = $e {
|
|
|
|
x
|
|
|
|
} else {
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
};
|
2017-03-16 02:57:17 -05:00
|
|
|
}
|
|
|
|
|
2020-06-25 15:41:36 -05:00
|
|
|
impl<'tcx> LateLintPass<'tcx> for NeedlessPassByValue {
|
2022-05-21 06:24:00 -05:00
|
|
|
#[expect(clippy::too_many_lines)]
|
2017-02-18 02:00:36 -06:00
|
|
|
fn check_fn(
|
|
|
|
&mut self,
|
2020-06-25 15:41:36 -05:00
|
|
|
cx: &LateContext<'tcx>,
|
2017-02-18 02:00:36 -06:00
|
|
|
kind: FnKind<'tcx>,
|
2019-12-29 22:02:10 -06:00
|
|
|
decl: &'tcx FnDecl<'_>,
|
2019-12-22 08:42:41 -06:00
|
|
|
body: &'tcx Body<'_>,
|
2017-02-18 02:00:36 -06:00
|
|
|
span: Span,
|
2023-01-22 12:00:33 -06:00
|
|
|
fn_def_id: LocalDefId,
|
2017-02-18 02:00:36 -06:00
|
|
|
) {
|
2019-08-19 11:30:32 -05:00
|
|
|
if span.from_expansion() {
|
2017-02-18 02:00:36 -06:00
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
2023-01-22 12:00:33 -06:00
|
|
|
let hir_id = cx.tcx.hir().local_def_id_to_hir_id(fn_def_id);
|
|
|
|
|
2017-03-12 17:30:18 -05:00
|
|
|
match kind {
|
2022-02-13 08:40:08 -06:00
|
|
|
FnKind::ItemFn(.., header) => {
|
2020-11-27 02:24:42 -06:00
|
|
|
let attrs = cx.tcx.hir().attrs(hir_id);
|
2019-03-11 06:45:57 -05:00
|
|
|
if header.abi != Abi::Rust || requires_exact_signature(attrs) {
|
2018-01-18 02:30:52 -06:00
|
|
|
return;
|
|
|
|
}
|
2017-03-12 17:30:18 -05:00
|
|
|
},
|
2017-11-03 03:24:10 -05:00
|
|
|
FnKind::Method(..) => (),
|
2020-11-27 02:24:42 -06:00
|
|
|
FnKind::Closure => return,
|
2017-02-18 02:00:36 -06:00
|
|
|
}
|
|
|
|
|
2017-11-03 03:24:10 -05:00
|
|
|
// Exclude non-inherent impls
|
2023-01-03 11:30:35 -06:00
|
|
|
if let Some(Node::Item(item)) = cx.tcx.hir().find_parent(hir_id) {
|
2020-12-20 10:19:49 -06:00
|
|
|
if matches!(
|
|
|
|
item.kind,
|
2020-11-22 16:46:21 -06:00
|
|
|
ItemKind::Impl(Impl { of_trait: Some(_), .. }) | ItemKind::Trait(..)
|
2020-12-20 10:19:49 -06:00
|
|
|
) {
|
2017-11-03 03:24:10 -05:00
|
|
|
return;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2017-10-08 04:04:45 -05:00
|
|
|
// Allow `Borrow` or functions to be taken by value
|
2020-07-07 10:12:44 -05:00
|
|
|
let allowed_traits = [
|
2017-10-08 04:04:45 -05:00
|
|
|
need!(cx.tcx.lang_items().fn_trait()),
|
|
|
|
need!(cx.tcx.lang_items().fn_once_trait()),
|
|
|
|
need!(cx.tcx.lang_items().fn_mut_trait()),
|
2019-05-17 16:53:54 -05:00
|
|
|
need!(get_trait_def_id(cx, &paths::RANGE_ARGUMENT_TRAIT)),
|
2017-10-08 04:04:45 -05:00
|
|
|
];
|
2017-10-07 20:23:41 -05:00
|
|
|
|
|
|
|
let sized_trait = need!(cx.tcx.lang_items().sized_trait());
|
2017-02-18 02:00:36 -06:00
|
|
|
|
2023-04-06 18:11:19 -05:00
|
|
|
let preds = traits::elaborate(cx.tcx, cx.param_env.caller_bounds().iter())
|
2022-01-11 21:19:52 -06:00
|
|
|
.filter(|p| !p.is_global())
|
2023-03-26 15:33:54 -05:00
|
|
|
.filter_map(|pred| {
|
2020-06-19 03:22:25 -05:00
|
|
|
// Note that we do not want to deal with qualified predicates here.
|
2023-03-26 15:33:54 -05:00
|
|
|
match pred.kind().no_bound_vars() {
|
2023-07-02 07:35:19 -05:00
|
|
|
Some(ty::ClauseKind::Trait(pred)) if pred.def_id() != sized_trait => Some(pred),
|
2020-12-21 21:49:03 -06:00
|
|
|
_ => None,
|
2017-10-08 06:17:04 -05:00
|
|
|
}
|
2017-10-07 20:23:41 -05:00
|
|
|
})
|
|
|
|
.collect::<Vec<_>>();
|
2017-02-19 21:50:31 -06:00
|
|
|
|
2017-08-09 02:30:56 -05:00
|
|
|
// Collect moved variables and spans which will need dereferencings from the
|
|
|
|
// function body.
|
2023-07-02 07:35:19 -05:00
|
|
|
let MovedVariablesCtxt { moved_vars } = {
|
2019-10-04 08:00:01 -05:00
|
|
|
let mut ctx = MovedVariablesCtxt::default();
|
2022-09-19 22:03:59 -05:00
|
|
|
let infcx = cx.tcx.infer_ctxt().build();
|
|
|
|
euv::ExprUseVisitor::new(&mut ctx, &infcx, fn_def_id, cx.param_env, cx.typeck_results()).consume_body(body);
|
2017-02-20 01:45:37 -06:00
|
|
|
ctx
|
2017-02-18 02:00:36 -06:00
|
|
|
};
|
|
|
|
|
2023-01-18 17:52:47 -06:00
|
|
|
let fn_sig = cx.tcx.fn_sig(fn_def_id).subst_identity();
|
2023-02-25 18:08:29 -06:00
|
|
|
let fn_sig = cx.tcx.liberate_late_bound_regions(fn_def_id.to_def_id(), fn_sig);
|
2017-02-18 02:00:36 -06:00
|
|
|
|
2019-12-22 08:56:34 -06:00
|
|
|
for (idx, ((input, &ty), arg)) in decl.inputs.iter().zip(fn_sig.inputs()).zip(body.params).enumerate() {
|
2017-10-17 17:29:47 -05:00
|
|
|
// All spans generated from a proc-macro invocation are the same...
|
|
|
|
if span == input.span {
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
2017-11-03 03:24:10 -05:00
|
|
|
// Ignore `self`s.
|
|
|
|
if idx == 0 {
|
2019-09-27 10:16:06 -05:00
|
|
|
if let PatKind::Binding(.., ident, _) = arg.pat.kind {
|
2021-01-15 03:56:44 -06:00
|
|
|
if ident.name == kw::SelfLower {
|
2017-11-03 03:24:10 -05:00
|
|
|
continue;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2020-08-11 08:43:21 -05:00
|
|
|
//
|
2017-10-07 20:23:41 -05:00
|
|
|
// * Exclude a type that is specifically bounded by `Borrow`.
|
2019-01-30 19:15:29 -06:00
|
|
|
// * Exclude a type whose reference also fulfills its bound. (e.g., `std::convert::AsRef`,
|
2018-11-27 14:14:15 -06:00
|
|
|
// `serde::Serialize`)
|
2017-10-07 20:23:41 -05:00
|
|
|
let (implements_borrow_trait, all_borrowable_trait) = {
|
2020-08-11 08:43:21 -05:00
|
|
|
let preds = preds.iter().filter(|t| t.self_ty() == ty).collect::<Vec<_>>();
|
2017-10-07 20:23:41 -05:00
|
|
|
|
|
|
|
(
|
2021-07-29 05:16:06 -05:00
|
|
|
preds.iter().any(|t| cx.tcx.is_diagnostic_item(sym::Borrow, t.def_id())),
|
2020-02-09 02:31:47 -06:00
|
|
|
!preds.is_empty() && {
|
2022-06-26 14:40:45 -05:00
|
|
|
let ty_empty_region = cx.tcx.mk_imm_ref(cx.tcx.lifetimes.re_erased, ty);
|
2020-02-09 02:31:47 -06:00
|
|
|
preds.iter().all(|t| {
|
2020-08-11 08:43:21 -05:00
|
|
|
let ty_params = t.trait_ref.substs.iter().skip(1).collect::<Vec<_>>();
|
2020-06-19 03:22:25 -05:00
|
|
|
implements_trait(cx, ty_empty_region, t.def_id(), &ty_params)
|
2020-02-09 02:31:47 -06:00
|
|
|
})
|
|
|
|
},
|
2017-10-07 20:23:41 -05:00
|
|
|
)
|
|
|
|
};
|
2017-02-19 21:50:31 -06:00
|
|
|
|
2017-10-23 14:18:02 -05:00
|
|
|
if_chain! {
|
|
|
|
if !is_self(arg);
|
2019-07-26 15:58:31 -05:00
|
|
|
if !ty.is_mutable_ptr();
|
2017-10-23 14:18:02 -05:00
|
|
|
if !is_copy(cx, ty);
|
2022-10-27 09:32:17 -05:00
|
|
|
if ty.is_sized(cx.tcx, cx.param_env);
|
2022-11-18 13:58:07 -06:00
|
|
|
if !allowed_traits.iter().any(|&t| implements_trait_with_env(cx.tcx, cx.param_env, ty, t, [None]));
|
2017-10-23 14:18:02 -05:00
|
|
|
if !implements_borrow_trait;
|
|
|
|
if !all_borrowable_trait;
|
|
|
|
|
2022-08-30 17:36:53 -05:00
|
|
|
if let PatKind::Binding(BindingAnnotation(_, Mutability::Not), canonical_id, ..) = arg.pat.kind;
|
2017-10-23 14:18:02 -05:00
|
|
|
if !moved_vars.contains(&canonical_id);
|
|
|
|
then {
|
|
|
|
// Dereference suggestion
|
2022-01-23 14:41:46 -06:00
|
|
|
let sugg = |diag: &mut Diagnostic| {
|
2020-08-03 17:18:29 -05:00
|
|
|
if let ty::Adt(def, ..) = ty.kind() {
|
2022-03-04 14:28:41 -06:00
|
|
|
if let Some(span) = cx.tcx.hir().span_if_local(def.did()) {
|
2022-11-30 14:41:02 -06:00
|
|
|
if type_allowed_to_implement_copy(
|
2022-03-14 06:02:53 -05:00
|
|
|
cx.tcx,
|
|
|
|
cx.param_env,
|
|
|
|
ty,
|
|
|
|
traits::ObligationCause::dummy_with_span(span),
|
|
|
|
).is_ok() {
|
2020-04-17 01:08:00 -05:00
|
|
|
diag.span_help(span, "consider marking this type as `Copy`");
|
2018-01-18 07:27:47 -06:00
|
|
|
}
|
2018-01-18 02:45:41 -06:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2017-10-23 14:18:02 -05:00
|
|
|
if_chain! {
|
2021-10-02 18:51:01 -05:00
|
|
|
if is_type_diagnostic_item(cx, ty, sym::Vec);
|
2017-10-23 14:18:02 -05:00
|
|
|
if let Some(clone_spans) =
|
2019-05-17 16:53:54 -05:00
|
|
|
get_spans(cx, Some(body.id()), idx, &[("clone", ".to_owned()")]);
|
2021-04-08 10:50:13 -05:00
|
|
|
if let TyKind::Path(QPath::Resolved(_, path)) = input.kind;
|
2017-10-23 14:18:02 -05:00
|
|
|
if let Some(elem_ty) = path.segments.iter()
|
2020-11-05 07:29:48 -06:00
|
|
|
.find(|seg| seg.ident.name == sym::Vec)
|
2018-06-24 08:32:40 -05:00
|
|
|
.and_then(|ps| ps.args.as_ref())
|
2018-06-24 16:42:52 -05:00
|
|
|
.map(|params| params.args.iter().find_map(|arg| match arg {
|
|
|
|
GenericArg::Type(ty) => Some(ty),
|
2019-02-19 01:34:43 -06:00
|
|
|
_ => None,
|
2018-06-24 16:42:52 -05:00
|
|
|
}).unwrap());
|
2017-10-23 14:18:02 -05:00
|
|
|
then {
|
|
|
|
let slice_ty = format!("&[{}]", snippet(cx, elem_ty.span, "_"));
|
2020-04-17 01:08:00 -05:00
|
|
|
diag.span_suggestion(
|
2018-09-18 10:07:54 -05:00
|
|
|
input.span,
|
|
|
|
"consider changing the type to",
|
|
|
|
slice_ty,
|
|
|
|
Applicability::Unspecified,
|
|
|
|
);
|
2017-11-03 03:24:10 -05:00
|
|
|
|
2017-10-23 14:18:02 -05:00
|
|
|
for (span, suggestion) in clone_spans {
|
2020-04-17 01:08:00 -05:00
|
|
|
diag.span_suggestion(
|
2017-10-23 14:18:02 -05:00
|
|
|
span,
|
2022-03-26 02:27:43 -05:00
|
|
|
snippet_opt(cx, span)
|
2017-10-23 14:18:02 -05:00
|
|
|
.map_or(
|
|
|
|
"change the call to".into(),
|
Use `Cow` in `{D,Subd}iagnosticMessage`.
Each of `{D,Subd}iagnosticMessage::{Str,Eager}` has a comment:
```
// FIXME(davidtwco): can a `Cow<'static, str>` be used here?
```
This commit answers that question in the affirmative. It's not the most
compelling change ever, but it might be worth merging.
This requires changing the `impl<'a> From<&'a str>` impls to `impl
From<&'static str>`, which involves a bunch of knock-on changes that
require/result in call sites being a little more precise about exactly
what kind of string they use to create errors, and not just `&str`. This
will result in fewer unnecessary allocations, though this will not have
any notable perf effects given that these are error paths.
Note that I was lazy within Clippy, using `to_string` in a few places to
preserve the existing string imprecision. I could have used `impl
Into<{D,Subd}iagnosticMessage>` in various places as is done in the
compiler, but that would have required changes to *many* call sites
(mostly changing `&format("...")` to `format!("...")`) which didn't seem
worthwhile.
2023-05-03 19:55:21 -05:00
|
|
|
|x| format!("change `{x}` to"),
|
|
|
|
),
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2022-04-26 00:17:33 -05:00
|
|
|
suggestion,
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2018-09-15 11:14:08 -05:00
|
|
|
Applicability::Unspecified,
|
2017-10-23 14:18:02 -05:00
|
|
|
);
|
|
|
|
}
|
2017-11-03 03:24:10 -05:00
|
|
|
|
2017-10-23 14:18:02 -05:00
|
|
|
// cannot be destructured, no need for `*` suggestion
|
|
|
|
return;
|
|
|
|
}
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2017-10-08 03:51:44 -05:00
|
|
|
}
|
2017-11-03 03:24:10 -05:00
|
|
|
|
2022-07-05 11:56:16 -05:00
|
|
|
if is_type_lang_item(cx, ty, LangItem::String) {
|
2017-10-23 14:18:02 -05:00
|
|
|
if let Some(clone_spans) =
|
2019-05-17 16:53:54 -05:00
|
|
|
get_spans(cx, Some(body.id()), idx, &[("clone", ".to_string()"), ("as_str", "")]) {
|
2020-04-17 01:08:00 -05:00
|
|
|
diag.span_suggestion(
|
2018-09-18 10:07:54 -05:00
|
|
|
input.span,
|
|
|
|
"consider changing the type to",
|
2022-06-13 01:48:40 -05:00
|
|
|
"&str",
|
2018-09-18 10:07:54 -05:00
|
|
|
Applicability::Unspecified,
|
|
|
|
);
|
2017-11-03 03:24:10 -05:00
|
|
|
|
2017-10-23 14:18:02 -05:00
|
|
|
for (span, suggestion) in clone_spans {
|
2020-04-17 01:08:00 -05:00
|
|
|
diag.span_suggestion(
|
2017-10-23 14:18:02 -05:00
|
|
|
span,
|
2022-03-26 02:27:43 -05:00
|
|
|
snippet_opt(cx, span)
|
2017-10-23 14:18:02 -05:00
|
|
|
.map_or(
|
|
|
|
"change the call to".into(),
|
Use `Cow` in `{D,Subd}iagnosticMessage`.
Each of `{D,Subd}iagnosticMessage::{Str,Eager}` has a comment:
```
// FIXME(davidtwco): can a `Cow<'static, str>` be used here?
```
This commit answers that question in the affirmative. It's not the most
compelling change ever, but it might be worth merging.
This requires changing the `impl<'a> From<&'a str>` impls to `impl
From<&'static str>`, which involves a bunch of knock-on changes that
require/result in call sites being a little more precise about exactly
what kind of string they use to create errors, and not just `&str`. This
will result in fewer unnecessary allocations, though this will not have
any notable perf effects given that these are error paths.
Note that I was lazy within Clippy, using `to_string` in a few places to
preserve the existing string imprecision. I could have used `impl
Into<{D,Subd}iagnosticMessage>` in various places as is done in the
compiler, but that would have required changes to *many* call sites
(mostly changing `&format("...")` to `format!("...")`) which didn't seem
worthwhile.
2023-05-03 19:55:21 -05:00
|
|
|
|x| format!("change `{x}` to")
|
|
|
|
),
|
2022-04-26 00:17:33 -05:00
|
|
|
suggestion,
|
2018-09-15 11:14:08 -05:00
|
|
|
Applicability::Unspecified,
|
2017-10-23 14:18:02 -05:00
|
|
|
);
|
|
|
|
}
|
2017-11-03 03:24:10 -05:00
|
|
|
|
2017-10-23 14:18:02 -05:00
|
|
|
return;
|
2017-10-08 03:51:44 -05:00
|
|
|
}
|
|
|
|
}
|
2017-11-03 03:24:10 -05:00
|
|
|
|
2023-07-02 07:35:19 -05:00
|
|
|
let spans = vec![(input.span, format!("&{}", snippet(cx, input.span, "_")))];
|
|
|
|
|
2020-05-17 10:36:26 -05:00
|
|
|
multispan_sugg(diag, "consider taking a reference instead", spans);
|
2017-10-23 14:18:02 -05:00
|
|
|
};
|
2017-11-03 03:24:10 -05:00
|
|
|
|
2017-10-23 14:18:02 -05:00
|
|
|
span_lint_and_then(
|
|
|
|
cx,
|
|
|
|
NEEDLESS_PASS_BY_VALUE,
|
|
|
|
input.span,
|
|
|
|
"this argument is passed by value, but not consumed in the function body",
|
|
|
|
sugg,
|
|
|
|
);
|
|
|
|
}
|
|
|
|
}
|
2017-02-18 02:00:36 -06:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2019-03-11 06:45:57 -05:00
|
|
|
/// Functions marked with these attributes must have the exact signature.
|
|
|
|
fn requires_exact_signature(attrs: &[Attribute]) -> bool {
|
|
|
|
attrs.iter().any(|attr| {
|
2020-11-05 07:29:48 -06:00
|
|
|
[sym::proc_macro, sym::proc_macro_attribute, sym::proc_macro_derive]
|
2019-03-11 06:45:57 -05:00
|
|
|
.iter()
|
2020-08-02 05:17:20 -05:00
|
|
|
.any(|&allow| attr.has_name(allow))
|
2019-03-11 06:45:57 -05:00
|
|
|
})
|
|
|
|
}
|
|
|
|
|
2019-10-04 08:00:01 -05:00
|
|
|
#[derive(Default)]
|
|
|
|
struct MovedVariablesCtxt {
|
2021-04-08 10:50:13 -05:00
|
|
|
moved_vars: HirIdSet,
|
2017-02-18 02:00:36 -06:00
|
|
|
}
|
|
|
|
|
2019-10-04 08:00:01 -05:00
|
|
|
impl MovedVariablesCtxt {
|
2020-06-17 17:13:05 -05:00
|
|
|
fn move_common(&mut self, cmt: &euv::PlaceWithHirId<'_>) {
|
|
|
|
if let euv::PlaceBase::Local(vid) = cmt.place.base {
|
2017-09-12 07:26:40 -05:00
|
|
|
self.moved_vars.insert(vid);
|
|
|
|
}
|
2017-02-18 02:00:36 -06:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2019-10-04 08:00:01 -05:00
|
|
|
impl<'tcx> euv::Delegate<'tcx> for MovedVariablesCtxt {
|
2021-07-14 01:21:08 -05:00
|
|
|
fn consume(&mut self, cmt: &euv::PlaceWithHirId<'tcx>, _: HirId) {
|
|
|
|
self.move_common(cmt);
|
2017-02-18 02:00:36 -06:00
|
|
|
}
|
|
|
|
|
2020-11-01 01:15:22 -06:00
|
|
|
fn borrow(&mut self, _: &euv::PlaceWithHirId<'tcx>, _: HirId, _: ty::BorrowKind) {}
|
2017-02-18 02:00:36 -06:00
|
|
|
|
2020-11-01 01:15:22 -06:00
|
|
|
fn mutate(&mut self, _: &euv::PlaceWithHirId<'tcx>, _: HirId) {}
|
2021-02-25 14:33:18 -06:00
|
|
|
|
2022-11-21 13:34:47 -06:00
|
|
|
fn fake_read(&mut self, _: &rustc_hir_typeck::expr_use_visitor::PlaceWithHirId<'tcx>, _: FakeReadCause, _: HirId) {}
|
2017-02-18 02:00:36 -06:00
|
|
|
}
|