//! Checks for usage of `&Vec[_]` and `&String`.
-use std::borrow::Cow;
-use rustc::hir::*;
+use crate::utils::ptr::get_spans;
+use crate::utils::{
+ is_type_diagnostic_item, match_qpath, match_type, paths, snippet_opt, span_lint, span_lint_and_then,
+ walk_ptrs_hir_ty,
+};
+use if_chain::if_chain;
use rustc::hir::QPath;
+use rustc::hir::*;
use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
-use rustc::{declare_lint, lint_array};
-use if_chain::if_chain;
use rustc::ty;
-use syntax::ast::NodeId;
+use rustc::{declare_lint_pass, declare_tool_lint};
+use rustc_errors::Applicability;
+use std::borrow::Cow;
use syntax::source_map::Span;
-use syntax_pos::MultiSpan;
-use crate::utils::{match_qpath, match_type, paths, snippet_opt, span_lint, span_lint_and_then, walk_ptrs_hir_ty};
-use crate::utils::ptr::get_spans;
+use syntax_pos::{MultiSpan, Symbol};
-/// **What it does:** This lint checks for function arguments of type `&String`
-/// or `&Vec` unless the references are mutable. It will also suggest you
-/// replace `.clone()` calls with the appropriate `.to_owned()`/`to_string()`
-/// calls.
-///
-/// **Why is this bad?** Requiring the argument to be of the specific size
-/// makes the function less useful for no benefit; slices in the form of `&[T]`
-/// or `&str` usually suffice and can be obtained from other types, too.
-///
-/// **Known problems:** The lint does not follow data. So if you have an
-/// argument `x` and write `let y = x; y.clone()` the lint will not suggest
-/// changing that `.clone()` to `.to_owned()`.
-///
-/// Other functions called from this function taking a `&String` or `&Vec`
-/// argument may also fail to compile if you change the argument. Applying
-/// this lint on them will fix the problem, but they may be in other crates.
-///
-/// Also there may be `fn(&Vec)`-typed references pointing to your function.
-/// If you have them, you will get a compiler error after applying this lint's
-/// suggestions. You then have the choice to undo your changes or change the
-/// type of the reference.
-///
-/// Note that if the function is part of your public interface, there may be
-/// other crates referencing it you may not be aware. Carefully deprecate the
-/// function before applying the lint suggestions in this case.
-///
-/// **Example:**
-/// ```rust
-/// fn foo(&Vec<u32>) { .. }
-/// ```
declare_clippy_lint! {
+ /// **What it does:** This lint checks for function arguments of type `&String`
+ /// or `&Vec` unless the references are mutable. It will also suggest you
+ /// replace `.clone()` calls with the appropriate `.to_owned()`/`to_string()`
+ /// calls.
+ ///
+ /// **Why is this bad?** Requiring the argument to be of the specific size
+ /// makes the function less useful for no benefit; slices in the form of `&[T]`
+ /// or `&str` usually suffice and can be obtained from other types, too.
+ ///
+ /// **Known problems:** The lint does not follow data. So if you have an
+ /// argument `x` and write `let y = x; y.clone()` the lint will not suggest
+ /// changing that `.clone()` to `.to_owned()`.
+ ///
+ /// Other functions called from this function taking a `&String` or `&Vec`
+ /// argument may also fail to compile if you change the argument. Applying
+ /// this lint on them will fix the problem, but they may be in other crates.
+ ///
+ /// Also there may be `fn(&Vec)`-typed references pointing to your function.
+ /// If you have them, you will get a compiler error after applying this lint's
+ /// suggestions. You then have the choice to undo your changes or change the
+ /// type of the reference.
+ ///
+ /// Note that if the function is part of your public interface, there may be
+ /// other crates referencing it you may not be aware. Carefully deprecate the
+ /// function before applying the lint suggestions in this case.
+ ///
+ /// **Example:**
+ /// ```ignore
+ /// fn foo(&Vec<u32>) { .. }
+ /// ```
pub PTR_ARG,
style,
- "fn arguments of the type `&Vec<...>` or `&String`, suggesting to use `&[...]` or `&str` \
- instead, respectively"
+ "fn arguments of the type `&Vec<...>` or `&String`, suggesting to use `&[...]` or `&str` instead, respectively"
}
-/// **What it does:** This lint checks for equality comparisons with `ptr::null`
-///
-/// **Why is this bad?** It's easier and more readable to use the inherent
-/// `.is_null()`
-/// method instead
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-/// ```rust
-/// if x == ptr::null { .. }
-/// ```
declare_clippy_lint! {
+ /// **What it does:** This lint checks for equality comparisons with `ptr::null`
+ ///
+ /// **Why is this bad?** It's easier and more readable to use the inherent
+ /// `.is_null()`
+ /// method instead
+ ///
+ /// **Known problems:** None.
+ ///
+ /// **Example:**
+ /// ```ignore
+ /// if x == ptr::null {
+ /// ..
+ /// }
+ /// ```
pub CMP_NULL,
style,
"comparing a pointer to a null pointer, suggesting to use `.is_null()` instead."
}
-/// **What it does:** This lint checks for functions that take immutable
-/// references and return
-/// mutable ones.
-///
-/// **Why is this bad?** This is trivially unsound, as one can create two
-/// mutable references
-/// from the same (immutable!) source. This
-/// [error](https://github.com/rust-lang/rust/issues/39465)
-/// actually lead to an interim Rust release 1.15.1.
-///
-/// **Known problems:** To be on the conservative side, if there's at least one
-/// mutable reference
-/// with the output lifetime, this lint will not trigger. In practice, this
-/// case is unlikely anyway.
-///
-/// **Example:**
-/// ```rust
-/// fn foo(&Foo) -> &mut Bar { .. }
-/// ```
declare_clippy_lint! {
+ /// **What it does:** This lint checks for functions that take immutable
+ /// references and return
+ /// mutable ones.
+ ///
+ /// **Why is this bad?** This is trivially unsound, as one can create two
+ /// mutable references
+ /// from the same (immutable!) source. This
+ /// [error](https://github.com/rust-lang/rust/issues/39465)
+ /// actually lead to an interim Rust release 1.15.1.
+ ///
+ /// **Known problems:** To be on the conservative side, if there's at least one
+ /// mutable reference
+ /// with the output lifetime, this lint will not trigger. In practice, this
+ /// case is unlikely anyway.
+ ///
+ /// **Example:**
+ /// ```ignore
+ /// fn foo(&Foo) -> &mut Bar { .. }
+ /// ```
pub MUT_FROM_REF,
correctness,
"fns that create mutable refs from immutable ref args"
}
-#[derive(Copy, Clone)]
-pub struct PointerPass;
-
-impl LintPass for PointerPass {
- fn get_lints(&self) -> LintArray {
- lint_array!(PTR_ARG, CMP_NULL, MUT_FROM_REF)
- }
-}
+declare_lint_pass!(Ptr => [PTR_ARG, CMP_NULL, MUT_FROM_REF]);
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for PointerPass {
+impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Ptr {
fn check_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx Item) {
if let ItemKind::Fn(ref decl, _, _, body_id) = item.node {
- check_fn(cx, decl, item.id, Some(body_id));
+ check_fn(cx, decl, item.hir_id, Some(body_id));
}
}
fn check_impl_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx ImplItem) {
if let ImplItemKind::Method(ref sig, body_id) = item.node {
- if let Some(Node::Item(it)) = cx.tcx.hir.find(cx.tcx.hir.get_parent(item.id)) {
+ let parent_item = cx.tcx.hir().get_parent_item(item.hir_id);
+ if let Some(Node::Item(it)) = cx.tcx.hir().find(parent_item) {
if let ItemKind::Impl(_, _, _, _, Some(_), _, _) = it.node {
return; // ignore trait impls
}
}
- check_fn(cx, &sig.decl, item.id, Some(body_id));
+ check_fn(cx, &sig.decl, item.hir_id, Some(body_id));
}
}
} else {
None
};
- check_fn(cx, &sig.decl, item.id, body_id);
+ check_fn(cx, &sig.decl, item.hir_id, body_id);
}
}
}
}
-fn check_fn(cx: &LateContext<'_, '_>, decl: &FnDecl, fn_id: NodeId, opt_body_id: Option<BodyId>) {
- let fn_def_id = cx.tcx.hir.local_def_id(fn_id);
+#[allow(clippy::too_many_lines)]
+fn check_fn(cx: &LateContext<'_, '_>, decl: &FnDecl, fn_id: HirId, opt_body_id: Option<BodyId>) {
+ let fn_def_id = cx.tcx.hir().local_def_id(fn_id);
let sig = cx.tcx.fn_sig(fn_def_id);
let fn_ty = sig.skip_binder();
for (idx, (arg, ty)) in decl.inputs.iter().zip(fn_ty.inputs()).enumerate() {
- if let ty::Ref(
- _,
- ty,
- MutImmutable
- ) = ty.sty
- {
- if match_type(cx, ty, &paths::VEC) {
+ if let ty::Ref(_, ty, MutImmutable) = ty.sty {
+ if is_type_diagnostic_item(cx, ty, Symbol::intern("vec_type")) {
let mut ty_snippet = None;
if_chain! {
if let TyKind::Path(QPath::Resolved(_, ref path)) = walk_ptrs_hir_ty(arg).node;
with non-Vec-based slices.",
|db| {
if let Some(ref snippet) = ty_snippet {
- db.span_suggestion(arg.span, "change this to", format!("&[{}]", snippet));
+ db.span_suggestion(
+ arg.span,
+ "change this to",
+ format!("&[{}]", snippet),
+ Applicability::Unspecified,
+ );
}
for (clonespan, suggestion) in spans {
db.span_suggestion(
clonespan,
- &snippet_opt(cx, clonespan).map_or(
- "change the call to".into(),
- |x| Cow::Owned(format!("change `{}` to", x)),
- ),
+ &snippet_opt(cx, clonespan).map_or("change the call to".into(), |x| {
+ Cow::Owned(format!("change `{}` to", x))
+ }),
suggestion.into(),
+ Applicability::Unspecified,
);
}
},
arg.span,
"writing `&String` instead of `&str` involves a new object where a slice will do.",
|db| {
- db.span_suggestion(arg.span, "change this to", "&str".into());
+ db.span_suggestion(arg.span, "change this to", "&str".into(), Applicability::Unspecified);
for (clonespan, suggestion) in spans {
db.span_suggestion_short(
clonespan,
- &snippet_opt(cx, clonespan).map_or(
- "change the call to".into(),
- |x| Cow::Owned(format!("change `{}` to", x)),
- ),
+ &snippet_opt(cx, clonespan).map_or("change the call to".into(), |x| {
+ Cow::Owned(format!("change `{}` to", x))
+ }),
suggestion.into(),
+ Applicability::Unspecified,
);
}
},
if !params.parenthesized;
if let Some(inner) = params.args.iter().find_map(|arg| match arg {
GenericArg::Type(ty) => Some(ty),
- GenericArg::Lifetime(_) => None,
+ _ => None,
});
then {
let replacement = snippet_opt(cx, inner.span);
arg.span,
"using a reference to `Cow` is not recommended.",
|db| {
- db.span_suggestion(arg.span, "change this to", "&".to_owned() + &r);
+ db.span_suggestion(
+ arg.span,
+ "change this to",
+ "&".to_owned() + &r,
+ Applicability::Unspecified,
+ );
},
);
}
if let FunctionRetTy::Return(ref ty) = decl.output {
if let Some((out, MutMutable, _)) = get_rptr_lm(ty) {
let mut immutables = vec![];
- for (_, ref mutbl, ref argspan) in decl.inputs
+ for (_, ref mutbl, ref argspan) in decl
+ .inputs
.iter()
.filter_map(|ty| get_rptr_lm(ty))
.filter(|&(lt, _, _)| lt.name == out.name)
if immutables.is_empty() {
return;
}
- span_lint_and_then(cx, MUT_FROM_REF, ty.span, "mutable borrow from immutable input(s)", |db| {
- let ms = MultiSpan::from_spans(immutables);
- db.span_note(ms, "immutable borrow here");
- });
+ span_lint_and_then(
+ cx,
+ MUT_FROM_REF,
+ ty.span,
+ "mutable borrow from immutable input(s)",
+ |db| {
+ let ms = MultiSpan::from_spans(immutables);
+ db.span_note(ms, "immutable borrow here");
+ },
+ );
}
}
}