mirror of
https://github.com/rust-lang/rust-clippy
synced 2024-12-24 03:53:20 +00:00
691 lines
24 KiB
Rust
691 lines
24 KiB
Rust
use crate::utils::{
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attrs::is_proc_macro, iter_input_pats, match_def_path, qpath_res, return_ty, snippet, snippet_opt,
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span_help_and_lint, span_lint, span_lint_and_then, type_is_unsafe_function,
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};
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use matches::matches;
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use rustc::hir::{self, def::Res, def_id::DefId, intravisit};
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use rustc::lint::{in_external_macro, LateContext, LateLintPass, LintArray, LintContext, LintPass};
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use rustc::ty::{self, Ty};
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use rustc::{declare_tool_lint, impl_lint_pass};
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use rustc_data_structures::fx::FxHashSet;
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use rustc_errors::Applicability;
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use rustc_target::spec::abi::Abi;
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use syntax::ast::Attribute;
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use syntax::source_map::Span;
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declare_clippy_lint! {
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/// **What it does:** Checks for functions with too many parameters.
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///
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/// **Why is this bad?** Functions with lots of parameters are considered bad
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/// style and reduce readability (“what does the 5th parameter mean?”). Consider
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/// grouping some parameters into a new type.
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///
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/// **Known problems:** None.
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///
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/// **Example:**
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/// ```rust
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/// # struct Color;
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/// fn foo(x: u32, y: u32, name: &str, c: Color, w: f32, h: f32, a: f32, b: f32) {
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/// // ..
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/// }
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/// ```
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pub TOO_MANY_ARGUMENTS,
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complexity,
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"functions with too many arguments"
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}
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declare_clippy_lint! {
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/// **What it does:** Checks for functions with a large amount of lines.
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///
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/// **Why is this bad?** Functions with a lot of lines are harder to understand
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/// due to having to look at a larger amount of code to understand what the
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/// function is doing. Consider splitting the body of the function into
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/// multiple functions.
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///
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/// **Known problems:** None.
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///
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/// **Example:**
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/// ``` rust
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/// fn im_too_long() {
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/// println!("");
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/// // ... 100 more LoC
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/// println!("");
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/// }
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/// ```
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pub TOO_MANY_LINES,
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pedantic,
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"functions with too many lines"
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}
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declare_clippy_lint! {
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/// **What it does:** Checks for public functions that dereference raw pointer
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/// arguments but are not marked unsafe.
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///
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/// **Why is this bad?** The function should probably be marked `unsafe`, since
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/// for an arbitrary raw pointer, there is no way of telling for sure if it is
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/// valid.
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///
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/// **Known problems:**
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///
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/// * It does not check functions recursively so if the pointer is passed to a
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/// private non-`unsafe` function which does the dereferencing, the lint won't
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/// trigger.
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/// * It only checks for arguments whose type are raw pointers, not raw pointers
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/// got from an argument in some other way (`fn foo(bar: &[*const u8])` or
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/// `some_argument.get_raw_ptr()`).
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///
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/// **Example:**
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/// ```rust
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/// pub fn foo(x: *const u8) {
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/// println!("{}", unsafe { *x });
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/// }
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/// ```
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pub NOT_UNSAFE_PTR_ARG_DEREF,
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correctness,
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"public functions dereferencing raw pointer arguments but not marked `unsafe`"
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}
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declare_clippy_lint! {
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/// **What it does:** Checks for a [`#[must_use]`] attribute on
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/// unit-returning functions and methods.
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///
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/// [`#[must_use]`]: https://doc.rust-lang.org/reference/attributes/diagnostics.html#the-must_use-attribute
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///
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/// **Why is this bad?** Unit values are useless. The attribute is likely
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/// a remnant of a refactoring that removed the return type.
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///
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/// **Known problems:** None.
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///
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/// **Examples:**
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/// ```rust
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/// #[must_use]
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/// fn useless() { }
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/// ```
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pub MUST_USE_UNIT,
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style,
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"`#[must_use]` attribute on a unit-returning function / method"
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}
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declare_clippy_lint! {
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/// **What it does:** Checks for a [`#[must_use]`] attribute without
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/// further information on functions and methods that return a type already
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/// marked as `#[must_use]`.
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///
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/// [`#[must_use]`]: https://doc.rust-lang.org/reference/attributes/diagnostics.html#the-must_use-attribute
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///
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/// **Why is this bad?** The attribute isn't needed. Not using the result
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/// will already be reported. Alternatively, one can add some text to the
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/// attribute to improve the lint message.
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///
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/// **Known problems:** None.
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///
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/// **Examples:**
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/// ```rust
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/// #[must_use]
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/// fn double_must_use() -> Result<(), ()> {
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/// unimplemented!();
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/// }
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/// ```
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pub DOUBLE_MUST_USE,
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style,
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"`#[must_use]` attribute on a `#[must_use]`-returning function / method"
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}
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declare_clippy_lint! {
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/// **What it does:** Checks for public functions that have no
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/// [`#[must_use]`] attribute, but return something not already marked
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/// must-use, have no mutable arg and mutate no statics.
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///
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/// [`#[must_use]`]: https://doc.rust-lang.org/reference/attributes/diagnostics.html#the-must_use-attribute
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///
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/// **Why is this bad?** Not bad at all, this lint just shows places where
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/// you could add the attribute.
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///
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/// **Known problems:** The lint only checks the arguments for mutable
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/// types without looking if they are actually changed. On the other hand,
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/// it also ignores a broad range of potentially interesting side effects,
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/// because we cannot decide whether the programmer intends the function to
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/// be called for the side effect or the result. Expect many false
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/// positives. At least we don't lint if the result type is unit or already
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/// `#[must_use]`.
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///
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/// **Examples:**
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/// ```rust
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/// // this could be annotated with `#[must_use]`.
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/// fn id<T>(t: T) -> T { t }
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/// ```
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pub MUST_USE_CANDIDATE,
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pedantic,
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"function or method that could take a `#[must_use]` attribute"
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}
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#[derive(Copy, Clone)]
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pub struct Functions {
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threshold: u64,
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max_lines: u64,
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}
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impl Functions {
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pub fn new(threshold: u64, max_lines: u64) -> Self {
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Self { threshold, max_lines }
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}
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}
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impl_lint_pass!(Functions => [
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TOO_MANY_ARGUMENTS,
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TOO_MANY_LINES,
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NOT_UNSAFE_PTR_ARG_DEREF,
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MUST_USE_UNIT,
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DOUBLE_MUST_USE,
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MUST_USE_CANDIDATE,
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]);
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impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Functions {
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fn check_fn(
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&mut self,
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cx: &LateContext<'a, 'tcx>,
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kind: intravisit::FnKind<'tcx>,
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decl: &'tcx hir::FnDecl,
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body: &'tcx hir::Body,
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span: Span,
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hir_id: hir::HirId,
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) {
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let is_impl = if let Some(hir::Node::Item(item)) = cx.tcx.hir().find(cx.tcx.hir().get_parent_node(hir_id)) {
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matches!(item.kind, hir::ItemKind::Impl(_, _, _, _, Some(_), _, _))
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} else {
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false
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};
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let unsafety = match kind {
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hir::intravisit::FnKind::ItemFn(_, _, hir::FnHeader { unsafety, .. }, _, _) => unsafety,
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hir::intravisit::FnKind::Method(_, sig, _, _) => sig.header.unsafety,
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hir::intravisit::FnKind::Closure(_) => return,
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};
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// don't warn for implementations, it's not their fault
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if !is_impl {
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// don't lint extern functions decls, it's not their fault either
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match kind {
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hir::intravisit::FnKind::Method(
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_,
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&hir::FnSig {
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header: hir::FnHeader { abi: Abi::Rust, .. },
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..
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},
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_,
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_,
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)
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| hir::intravisit::FnKind::ItemFn(_, _, hir::FnHeader { abi: Abi::Rust, .. }, _, _) => {
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self.check_arg_number(cx, decl, span.with_hi(decl.output.span().hi()))
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},
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_ => {},
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}
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}
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Self::check_raw_ptr(cx, unsafety, decl, body, hir_id);
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self.check_line_number(cx, span, body);
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}
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fn check_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx hir::Item) {
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let attr = must_use_attr(&item.attrs);
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if let hir::ItemKind::Fn(ref sig, ref _generics, ref body_id) = item.kind {
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if let Some(attr) = attr {
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let fn_header_span = item.span.with_hi(sig.decl.output.span().hi());
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check_needless_must_use(cx, &sig.decl, item.hir_id, item.span, fn_header_span, attr);
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return;
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}
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if cx.access_levels.is_exported(item.hir_id) && !is_proc_macro(&item.attrs) {
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check_must_use_candidate(
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cx,
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&sig.decl,
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cx.tcx.hir().body(*body_id),
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item.span,
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item.hir_id,
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item.span.with_hi(sig.decl.output.span().hi()),
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"this function could have a `#[must_use]` attribute",
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);
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}
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}
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}
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fn check_impl_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx hir::ImplItem) {
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if let hir::ImplItemKind::Method(ref sig, ref body_id) = item.kind {
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let attr = must_use_attr(&item.attrs);
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if let Some(attr) = attr {
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let fn_header_span = item.span.with_hi(sig.decl.output.span().hi());
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check_needless_must_use(cx, &sig.decl, item.hir_id, item.span, fn_header_span, attr);
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} else if cx.access_levels.is_exported(item.hir_id) && !is_proc_macro(&item.attrs) {
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check_must_use_candidate(
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cx,
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&sig.decl,
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cx.tcx.hir().body(*body_id),
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item.span,
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item.hir_id,
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item.span.with_hi(sig.decl.output.span().hi()),
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"this method could have a `#[must_use]` attribute",
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);
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}
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}
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}
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fn check_trait_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx hir::TraitItem) {
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if let hir::TraitItemKind::Method(ref sig, ref eid) = item.kind {
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// don't lint extern functions decls, it's not their fault
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if sig.header.abi == Abi::Rust {
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self.check_arg_number(cx, &sig.decl, item.span.with_hi(sig.decl.output.span().hi()));
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}
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let attr = must_use_attr(&item.attrs);
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if let Some(attr) = attr {
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let fn_header_span = item.span.with_hi(sig.decl.output.span().hi());
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check_needless_must_use(cx, &sig.decl, item.hir_id, item.span, fn_header_span, attr);
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}
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if let hir::TraitMethod::Provided(eid) = *eid {
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let body = cx.tcx.hir().body(eid);
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Self::check_raw_ptr(cx, sig.header.unsafety, &sig.decl, body, item.hir_id);
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if attr.is_none() && cx.access_levels.is_exported(item.hir_id) && !is_proc_macro(&item.attrs) {
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check_must_use_candidate(
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cx,
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&sig.decl,
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body,
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item.span,
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item.hir_id,
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item.span.with_hi(sig.decl.output.span().hi()),
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"this method could have a `#[must_use]` attribute",
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);
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}
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}
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}
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}
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}
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impl<'a, 'tcx> Functions {
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fn check_arg_number(self, cx: &LateContext<'_, '_>, decl: &hir::FnDecl, fn_span: Span) {
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let args = decl.inputs.len() as u64;
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if args > self.threshold {
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span_lint(
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cx,
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TOO_MANY_ARGUMENTS,
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fn_span,
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&format!("this function has too many arguments ({}/{})", args, self.threshold),
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);
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}
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}
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fn check_line_number(self, cx: &LateContext<'_, '_>, span: Span, body: &'tcx hir::Body) {
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if in_external_macro(cx.sess(), span) {
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return;
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}
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let code_snippet = snippet(cx, body.value.span, "..");
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let mut line_count: u64 = 0;
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let mut in_comment = false;
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let mut code_in_line;
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// Skip the surrounding function decl.
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let start_brace_idx = code_snippet.find('{').map_or(0, |i| i + 1);
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let end_brace_idx = code_snippet.rfind('}').unwrap_or_else(|| code_snippet.len());
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let function_lines = code_snippet[start_brace_idx..end_brace_idx].lines();
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for mut line in function_lines {
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code_in_line = false;
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loop {
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line = line.trim_start();
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if line.is_empty() {
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break;
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}
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if in_comment {
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match line.find("*/") {
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Some(i) => {
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line = &line[i + 2..];
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in_comment = false;
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continue;
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},
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None => break,
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}
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} else {
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let multi_idx = line.find("/*").unwrap_or_else(|| line.len());
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let single_idx = line.find("//").unwrap_or_else(|| line.len());
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code_in_line |= multi_idx > 0 && single_idx > 0;
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// Implies multi_idx is below line.len()
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if multi_idx < single_idx {
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line = &line[multi_idx + 2..];
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in_comment = true;
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continue;
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}
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break;
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}
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}
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if code_in_line {
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line_count += 1;
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}
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}
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if line_count > self.max_lines {
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span_lint(cx, TOO_MANY_LINES, span, "This function has a large number of lines.")
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}
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}
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fn check_raw_ptr(
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cx: &LateContext<'a, 'tcx>,
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unsafety: hir::Unsafety,
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decl: &'tcx hir::FnDecl,
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body: &'tcx hir::Body,
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hir_id: hir::HirId,
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) {
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let expr = &body.value;
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if unsafety == hir::Unsafety::Normal && cx.access_levels.is_exported(hir_id) {
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let raw_ptrs = iter_input_pats(decl, body)
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.zip(decl.inputs.iter())
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.filter_map(|(arg, ty)| raw_ptr_arg(arg, ty))
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.collect::<FxHashSet<_>>();
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if !raw_ptrs.is_empty() {
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let tables = cx.tcx.body_tables(body.id());
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let mut v = DerefVisitor {
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cx,
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ptrs: raw_ptrs,
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tables,
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};
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hir::intravisit::walk_expr(&mut v, expr);
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}
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}
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}
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}
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fn check_needless_must_use(
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cx: &LateContext<'_, '_>,
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decl: &hir::FnDecl,
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item_id: hir::HirId,
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item_span: Span,
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fn_header_span: Span,
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attr: &Attribute,
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) {
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if in_external_macro(cx.sess(), item_span) {
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return;
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}
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if returns_unit(decl) {
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span_lint_and_then(
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cx,
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MUST_USE_UNIT,
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fn_header_span,
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"this unit-returning function has a `#[must_use]` attribute",
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|db| {
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db.span_suggestion(
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attr.span,
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"remove the attribute",
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"".into(),
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Applicability::MachineApplicable,
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);
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},
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);
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} else if !attr.is_value_str() && is_must_use_ty(cx, return_ty(cx, item_id)) {
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span_help_and_lint(
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cx,
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DOUBLE_MUST_USE,
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fn_header_span,
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"this function has an empty `#[must_use]` attribute, but returns a type already marked as `#[must_use]`",
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"either add some descriptive text or remove the attribute",
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);
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}
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}
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fn check_must_use_candidate<'a, 'tcx>(
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cx: &LateContext<'a, 'tcx>,
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decl: &'tcx hir::FnDecl,
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body: &'tcx hir::Body,
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item_span: Span,
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item_id: hir::HirId,
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fn_span: Span,
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msg: &str,
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) {
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if has_mutable_arg(cx, body)
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|| mutates_static(cx, body)
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|| in_external_macro(cx.sess(), item_span)
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|| returns_unit(decl)
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|| is_must_use_ty(cx, return_ty(cx, item_id))
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{
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return;
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}
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span_lint_and_then(cx, MUST_USE_CANDIDATE, fn_span, msg, |db| {
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if let Some(snippet) = snippet_opt(cx, fn_span) {
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db.span_suggestion(
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fn_span,
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"add the attribute",
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format!("#[must_use] {}", snippet),
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Applicability::MachineApplicable,
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);
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}
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});
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}
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|
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fn must_use_attr(attrs: &[Attribute]) -> Option<&Attribute> {
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attrs.iter().find(|attr| {
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attr.ident().map_or(false, |ident| {
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let ident: &str = &ident.as_str();
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"must_use" == ident
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})
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})
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}
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fn returns_unit(decl: &hir::FnDecl) -> bool {
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match decl.output {
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hir::FunctionRetTy::DefaultReturn(_) => true,
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|
hir::FunctionRetTy::Return(ref ty) => match ty.kind {
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hir::TyKind::Tup(ref tys) => tys.is_empty(),
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|
hir::TyKind::Never => true,
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_ => false,
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},
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|
}
|
|
}
|
|
|
|
fn is_must_use_ty<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, ty: Ty<'tcx>) -> bool {
|
|
use ty::TyKind::*;
|
|
match ty.kind {
|
|
Adt(ref adt, _) => must_use_attr(&cx.tcx.get_attrs(adt.did)).is_some(),
|
|
Foreign(ref did) => must_use_attr(&cx.tcx.get_attrs(*did)).is_some(),
|
|
Slice(ref ty) | Array(ref ty, _) | RawPtr(ty::TypeAndMut { ref ty, .. }) | Ref(_, ref ty, _) => {
|
|
// for the Array case we don't need to care for the len == 0 case
|
|
// because we don't want to lint functions returning empty arrays
|
|
is_must_use_ty(cx, *ty)
|
|
},
|
|
Tuple(ref substs) => substs.types().any(|ty| is_must_use_ty(cx, ty)),
|
|
Opaque(ref def_id, _) => {
|
|
for (predicate, _) in cx.tcx.predicates_of(*def_id).predicates {
|
|
if let ty::Predicate::Trait(ref poly_trait_predicate) = predicate {
|
|
if must_use_attr(&cx.tcx.get_attrs(poly_trait_predicate.skip_binder().trait_ref.def_id)).is_some() {
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
false
|
|
},
|
|
Dynamic(binder, _) => {
|
|
for predicate in binder.skip_binder().iter() {
|
|
if let ty::ExistentialPredicate::Trait(ref trait_ref) = predicate {
|
|
if must_use_attr(&cx.tcx.get_attrs(trait_ref.def_id)).is_some() {
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
false
|
|
},
|
|
_ => false,
|
|
}
|
|
}
|
|
|
|
fn has_mutable_arg(cx: &LateContext<'_, '_>, body: &hir::Body) -> bool {
|
|
let mut tys = FxHashSet::default();
|
|
body.params.iter().any(|param| is_mutable_pat(cx, ¶m.pat, &mut tys))
|
|
}
|
|
|
|
fn is_mutable_pat(cx: &LateContext<'_, '_>, pat: &hir::Pat, tys: &mut FxHashSet<DefId>) -> bool {
|
|
if let hir::PatKind::Wild = pat.kind {
|
|
return false; // ignore `_` patterns
|
|
}
|
|
let def_id = pat.hir_id.owner_def_id();
|
|
if cx.tcx.has_typeck_tables(def_id) {
|
|
is_mutable_ty(cx, &cx.tcx.typeck_tables_of(def_id).pat_ty(pat), pat.span, tys)
|
|
} else {
|
|
false
|
|
}
|
|
}
|
|
|
|
static KNOWN_WRAPPER_TYS: &[&[&str]] = &[&["alloc", "rc", "Rc"], &["std", "sync", "Arc"]];
|
|
|
|
fn is_mutable_ty<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, ty: Ty<'tcx>, span: Span, tys: &mut FxHashSet<DefId>) -> bool {
|
|
use ty::TyKind::*;
|
|
match ty.kind {
|
|
// primitive types are never mutable
|
|
Bool | Char | Int(_) | Uint(_) | Float(_) | Str => false,
|
|
Adt(ref adt, ref substs) => {
|
|
tys.insert(adt.did) && !ty.is_freeze(cx.tcx, cx.param_env, span)
|
|
|| KNOWN_WRAPPER_TYS.iter().any(|path| match_def_path(cx, adt.did, path))
|
|
&& substs.types().any(|ty| is_mutable_ty(cx, ty, span, tys))
|
|
},
|
|
Tuple(ref substs) => substs.types().any(|ty| is_mutable_ty(cx, ty, span, tys)),
|
|
Array(ty, _) | Slice(ty) => is_mutable_ty(cx, ty, span, tys),
|
|
RawPtr(ty::TypeAndMut { ty, mutbl }) | Ref(_, ty, mutbl) => {
|
|
mutbl == hir::Mutability::Mutable || is_mutable_ty(cx, ty, span, tys)
|
|
},
|
|
// calling something constitutes a side effect, so return true on all callables
|
|
// also never calls need not be used, so return true for them, too
|
|
_ => true,
|
|
}
|
|
}
|
|
|
|
fn raw_ptr_arg(arg: &hir::Param, ty: &hir::Ty) -> Option<hir::HirId> {
|
|
if let (&hir::PatKind::Binding(_, id, _, _), &hir::TyKind::Ptr(_)) = (&arg.pat.kind, &ty.kind) {
|
|
Some(id)
|
|
} else {
|
|
None
|
|
}
|
|
}
|
|
|
|
struct DerefVisitor<'a, 'tcx> {
|
|
cx: &'a LateContext<'a, 'tcx>,
|
|
ptrs: FxHashSet<hir::HirId>,
|
|
tables: &'a ty::TypeckTables<'tcx>,
|
|
}
|
|
|
|
impl<'a, 'tcx> intravisit::Visitor<'tcx> for DerefVisitor<'a, 'tcx> {
|
|
fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
|
|
match expr.kind {
|
|
hir::ExprKind::Call(ref f, ref args) => {
|
|
let ty = self.tables.expr_ty(f);
|
|
|
|
if type_is_unsafe_function(self.cx, ty) {
|
|
for arg in args {
|
|
self.check_arg(arg);
|
|
}
|
|
}
|
|
},
|
|
hir::ExprKind::MethodCall(_, _, ref args) => {
|
|
let def_id = self.tables.type_dependent_def_id(expr.hir_id).unwrap();
|
|
let base_type = self.cx.tcx.type_of(def_id);
|
|
|
|
if type_is_unsafe_function(self.cx, base_type) {
|
|
for arg in args {
|
|
self.check_arg(arg);
|
|
}
|
|
}
|
|
},
|
|
hir::ExprKind::Unary(hir::UnDeref, ref ptr) => self.check_arg(ptr),
|
|
_ => (),
|
|
}
|
|
|
|
intravisit::walk_expr(self, expr);
|
|
}
|
|
|
|
fn nested_visit_map<'this>(&'this mut self) -> intravisit::NestedVisitorMap<'this, 'tcx> {
|
|
intravisit::NestedVisitorMap::None
|
|
}
|
|
}
|
|
|
|
impl<'a, 'tcx> DerefVisitor<'a, 'tcx> {
|
|
fn check_arg(&self, ptr: &hir::Expr) {
|
|
if let hir::ExprKind::Path(ref qpath) = ptr.kind {
|
|
if let Res::Local(id) = qpath_res(self.cx, qpath, ptr.hir_id) {
|
|
if self.ptrs.contains(&id) {
|
|
span_lint(
|
|
self.cx,
|
|
NOT_UNSAFE_PTR_ARG_DEREF,
|
|
ptr.span,
|
|
"this public function dereferences a raw pointer but is not marked `unsafe`",
|
|
);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
struct StaticMutVisitor<'a, 'tcx> {
|
|
cx: &'a LateContext<'a, 'tcx>,
|
|
mutates_static: bool,
|
|
}
|
|
|
|
impl<'a, 'tcx> intravisit::Visitor<'tcx> for StaticMutVisitor<'a, 'tcx> {
|
|
fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
|
|
use hir::ExprKind::*;
|
|
|
|
if self.mutates_static {
|
|
return;
|
|
}
|
|
match expr.kind {
|
|
Call(_, ref args) | MethodCall(_, _, ref args) => {
|
|
let mut tys = FxHashSet::default();
|
|
for arg in args {
|
|
let def_id = arg.hir_id.owner_def_id();
|
|
if self.cx.tcx.has_typeck_tables(def_id)
|
|
&& is_mutable_ty(
|
|
self.cx,
|
|
self.cx.tcx.typeck_tables_of(def_id).expr_ty(arg),
|
|
arg.span,
|
|
&mut tys,
|
|
)
|
|
&& is_mutated_static(self.cx, arg)
|
|
{
|
|
self.mutates_static = true;
|
|
return;
|
|
}
|
|
tys.clear();
|
|
}
|
|
},
|
|
Assign(ref target, _) | AssignOp(_, ref target, _) | AddrOf(hir::Mutability::Mutable, ref target) => {
|
|
self.mutates_static |= is_mutated_static(self.cx, target)
|
|
},
|
|
_ => {},
|
|
}
|
|
}
|
|
|
|
fn nested_visit_map<'this>(&'this mut self) -> intravisit::NestedVisitorMap<'this, 'tcx> {
|
|
intravisit::NestedVisitorMap::None
|
|
}
|
|
}
|
|
|
|
fn is_mutated_static(cx: &LateContext<'_, '_>, e: &hir::Expr) -> bool {
|
|
use hir::ExprKind::*;
|
|
|
|
match e.kind {
|
|
Path(ref qpath) => {
|
|
if let Res::Local(_) = qpath_res(cx, qpath, e.hir_id) {
|
|
false
|
|
} else {
|
|
true
|
|
}
|
|
},
|
|
Field(ref inner, _) | Index(ref inner, _) => is_mutated_static(cx, inner),
|
|
_ => false,
|
|
}
|
|
}
|
|
|
|
fn mutates_static<'a, 'tcx>(cx: &'a LateContext<'a, 'tcx>, body: &'tcx hir::Body) -> bool {
|
|
let mut v = StaticMutVisitor {
|
|
cx,
|
|
mutates_static: false,
|
|
};
|
|
intravisit::walk_expr(&mut v, &body.value);
|
|
v.mutates_static
|
|
}
|