//! checks for attributes
use clippy_utils::diagnostics::{span_lint, span_lint_and_help, span_lint_and_sugg, span_lint_and_then};
-use clippy_utils::match_panic_def_id;
+use clippy_utils::macros::{is_panic, macro_backtrace};
+use clippy_utils::msrvs;
use clippy_utils::source::{first_line_of_span, is_present_in_source, snippet_opt, without_block_comments};
+use clippy_utils::{extract_msrv_attr, meets_msrv};
use if_chain::if_chain;
use rustc_ast::{AttrKind, AttrStyle, Attribute, Lit, LitKind, MetaItemKind, NestedMetaItem};
use rustc_errors::Applicability;
use rustc_lint::{EarlyContext, EarlyLintPass, LateContext, LateLintPass, LintContext};
use rustc_middle::lint::in_external_macro;
use rustc_middle::ty;
-use rustc_session::{declare_lint_pass, declare_tool_lint};
+use rustc_semver::RustcVersion;
+use rustc_session::{declare_lint_pass, declare_tool_lint, impl_lint_pass};
use rustc_span::source_map::Span;
use rustc_span::sym;
-use rustc_span::symbol::{Symbol, SymbolStr};
+use rustc_span::symbol::Symbol;
use semver::Version;
static UNIX_SYSTEMS: &[&str] = &[
static NON_UNIX_SYSTEMS: &[&str] = &["hermit", "none", "wasi"];
declare_clippy_lint! {
- /// **What it does:** Checks for items annotated with `#[inline(always)]`,
+ /// ### What it does
+ /// Checks for items annotated with `#[inline(always)]`,
/// unless the annotated function is empty or simply panics.
///
- /// **Why is this bad?** While there are valid uses of this annotation (and once
+ /// ### Why is this bad?
+ /// While there are valid uses of this annotation (and once
/// you know when to use it, by all means `allow` this lint), it's a common
/// newbie-mistake to pepper one's code with it.
///
/// measure if that additional function call really affects your runtime profile
/// sufficiently to make up for the increase in compile time.
///
- /// **Known problems:** False positives, big time. This lint is meant to be
+ /// ### Known problems
+ /// False positives, big time. This lint is meant to be
/// deactivated by everyone doing serious performance work. This means having
/// done the measurement.
///
- /// **Example:**
+ /// ### Example
/// ```ignore
/// #[inline(always)]
/// fn not_quite_hot_code(..) { ... }
/// ```
+ #[clippy::version = "pre 1.29.0"]
pub INLINE_ALWAYS,
pedantic,
"use of `#[inline(always)]`"
}
declare_clippy_lint! {
- /// **What it does:** Checks for `extern crate` and `use` items annotated with
+ /// ### What it does
+ /// Checks for `extern crate` and `use` items annotated with
/// lint attributes.
///
/// This lint permits `#[allow(unused_imports)]`, `#[allow(deprecated)]`,
/// `#[allow(clippy::enum_glob_use)]` on `use` items and `#[allow(unused_imports)]` on
/// `extern crate` items with a `#[macro_use]` attribute.
///
- /// **Why is this bad?** Lint attributes have no effect on crate imports. Most
+ /// ### Why is this bad?
+ /// Lint attributes have no effect on crate imports. Most
/// likely a `!` was forgotten.
///
- /// **Known problems:** None.
- ///
- /// **Example:**
+ /// ### Example
/// ```ignore
/// // Bad
/// #[deny(dead_code)]
/// #[macro_use]
/// extern crate baz;
/// ```
+ #[clippy::version = "pre 1.29.0"]
pub USELESS_ATTRIBUTE,
correctness,
"use of lint attributes on `extern crate` items"
}
declare_clippy_lint! {
- /// **What it does:** Checks for `#[deprecated]` annotations with a `since`
+ /// ### What it does
+ /// Checks for `#[deprecated]` annotations with a `since`
/// field that is not a valid semantic version.
///
- /// **Why is this bad?** For checking the version of the deprecation, it must be
+ /// ### Why is this bad?
+ /// For checking the version of the deprecation, it must be
/// a valid semver. Failing that, the contained information is useless.
///
- /// **Known problems:** None.
- ///
- /// **Example:**
+ /// ### Example
/// ```rust
/// #[deprecated(since = "forever")]
/// fn something_else() { /* ... */ }
/// ```
+ #[clippy::version = "pre 1.29.0"]
pub DEPRECATED_SEMVER,
correctness,
"use of `#[deprecated(since = \"x\")]` where x is not semver"
}
declare_clippy_lint! {
- /// **What it does:** Checks for empty lines after outer attributes
+ /// ### What it does
+ /// Checks for empty lines after outer attributes
///
- /// **Why is this bad?**
+ /// ### Why is this bad?
/// Most likely the attribute was meant to be an inner attribute using a '!'.
/// If it was meant to be an outer attribute, then the following item
/// should not be separated by empty lines.
///
- /// **Known problems:** Can cause false positives.
+ /// ### Known problems
+ /// Can cause false positives.
///
/// From the clippy side it's difficult to detect empty lines between an attributes and the
/// following item because empty lines and comments are not part of the AST. The parsing
/// currently works for basic cases but is not perfect.
///
- /// **Example:**
+ /// ### Example
/// ```rust
/// // Good (as inner attribute)
/// #![allow(dead_code)]
/// #[allow(dead_code)]
/// fn this_is_fine_too() { }
/// ```
+ #[clippy::version = "pre 1.29.0"]
pub EMPTY_LINE_AFTER_OUTER_ATTR,
nursery,
"empty line after outer attribute"
}
declare_clippy_lint! {
- /// **What it does:** Checks for `warn`/`deny`/`forbid` attributes targeting the whole clippy::restriction category.
+ /// ### What it does
+ /// Checks for `warn`/`deny`/`forbid` attributes targeting the whole clippy::restriction category.
///
- /// **Why is this bad?** Restriction lints sometimes are in contrast with other lints or even go against idiomatic rust.
+ /// ### Why is this bad?
+ /// Restriction lints sometimes are in contrast with other lints or even go against idiomatic rust.
/// These lints should only be enabled on a lint-by-lint basis and with careful consideration.
///
- /// **Known problems:** None.
- ///
- /// **Example:**
+ /// ### Example
/// Bad:
/// ```rust
/// #![deny(clippy::restriction)]
/// ```rust
/// #![deny(clippy::as_conversions)]
/// ```
+ #[clippy::version = "1.47.0"]
pub BLANKET_CLIPPY_RESTRICTION_LINTS,
suspicious,
"enabling the complete restriction group"
}
declare_clippy_lint! {
- /// **What it does:** Checks for `#[cfg_attr(rustfmt, rustfmt_skip)]` and suggests to replace it
+ /// ### What it does
+ /// Checks for `#[cfg_attr(rustfmt, rustfmt_skip)]` and suggests to replace it
/// with `#[rustfmt::skip]`.
///
- /// **Why is this bad?** Since tool_attributes ([rust-lang/rust#44690](https://github.com/rust-lang/rust/issues/44690))
+ /// ### Why is this bad?
+ /// Since tool_attributes ([rust-lang/rust#44690](https://github.com/rust-lang/rust/issues/44690))
/// are stable now, they should be used instead of the old `cfg_attr(rustfmt)` attributes.
///
- /// **Known problems:** This lint doesn't detect crate level inner attributes, because they get
+ /// ### Known problems
+ /// This lint doesn't detect crate level inner attributes, because they get
/// processed before the PreExpansionPass lints get executed. See
/// [#3123](https://github.com/rust-lang/rust-clippy/pull/3123#issuecomment-422321765)
///
- /// **Example:**
- ///
+ /// ### Example
/// Bad:
/// ```rust
/// #[cfg_attr(rustfmt, rustfmt_skip)]
/// #[rustfmt::skip]
/// fn main() { }
/// ```
+ #[clippy::version = "1.32.0"]
pub DEPRECATED_CFG_ATTR,
complexity,
"usage of `cfg_attr(rustfmt)` instead of tool attributes"
}
declare_clippy_lint! {
- /// **What it does:** Checks for cfg attributes having operating systems used in target family position.
+ /// ### What it does
+ /// Checks for cfg attributes having operating systems used in target family position.
///
- /// **Why is this bad?** The configuration option will not be recognised and the related item will not be included
+ /// ### Why is this bad?
+ /// The configuration option will not be recognised and the related item will not be included
/// by the conditional compilation engine.
///
- /// **Known problems:** None.
- ///
- /// **Example:**
- ///
+ /// ### Example
/// Bad:
/// ```rust
/// #[cfg(linux)]
/// fn conditional() { }
/// ```
/// Check the [Rust Reference](https://doc.rust-lang.org/reference/conditional-compilation.html#target_os) for more details.
+ #[clippy::version = "1.45.0"]
pub MISMATCHED_TARGET_OS,
correctness,
"usage of `cfg(operating_system)` instead of `cfg(target_os = \"operating_system\")`"
}
+declare_clippy_lint! {
+ /// ### What it does
+ /// Checks for attributes that allow lints without a reason.
+ ///
+ /// (This requires the `lint_reasons` feature)
+ ///
+ /// ### Why is this bad?
+ /// Allowing a lint should always have a reason. This reason should be documented to
+ /// ensure that others understand the reasoning
+ ///
+ /// ### Example
+ /// Bad:
+ /// ```rust
+ /// #![feature(lint_reasons)]
+ ///
+ /// #![allow(clippy::some_lint)]
+ /// ```
+ ///
+ /// Good:
+ /// ```rust
+ /// #![feature(lint_reasons)]
+ ///
+ /// #![allow(clippy::some_lint, reason = "False positive rust-lang/rust-clippy#1002020")]
+ /// ```
+ #[clippy::version = "1.61.0"]
+ pub ALLOW_ATTRIBUTES_WITHOUT_REASON,
+ restriction,
+ "ensures that all `allow` and `expect` attributes have a reason"
+}
+
declare_lint_pass!(Attributes => [
+ ALLOW_ATTRIBUTES_WITHOUT_REASON,
INLINE_ALWAYS,
DEPRECATED_SEMVER,
USELESS_ATTRIBUTE,
if is_lint_level(ident.name) {
check_clippy_lint_names(cx, ident.name, items);
}
+ if matches!(ident.name, sym::allow | sym::expect) {
+ check_lint_reason(cx, ident.name, items, attr);
+ }
if items.is_empty() || !attr.has_name(sym::deprecated) {
return;
}
|| is_word(lint, sym::deprecated)
|| is_word(lint, sym!(unreachable_pub))
|| is_word(lint, sym!(unused))
- || extract_clippy_lint(lint).map_or(false, |s| s == "wildcard_imports")
- || extract_clippy_lint(lint).map_or(false, |s| s == "enum_glob_use")
+ || extract_clippy_lint(lint)
+ .map_or(false, |s| s.as_str() == "wildcard_imports")
+ || extract_clippy_lint(lint)
+ .map_or(false, |s| s.as_str() == "enum_glob_use")
{
return;
}
}
/// Returns the lint name if it is clippy lint.
-fn extract_clippy_lint(lint: &NestedMetaItem) -> Option<SymbolStr> {
+fn extract_clippy_lint(lint: &NestedMetaItem) -> Option<Symbol> {
if_chain! {
if let Some(meta_item) = lint.meta_item();
if meta_item.path.segments.len() > 1;
if tool_name.name == sym::clippy;
then {
let lint_name = meta_item.path.segments.last().unwrap().ident.name;
- return Some(lint_name.as_str());
+ return Some(lint_name);
}
}
None
fn check_clippy_lint_names(cx: &LateContext<'_>, name: Symbol, items: &[NestedMetaItem]) {
for lint in items {
if let Some(lint_name) = extract_clippy_lint(lint) {
- if lint_name == "restriction" && name != sym::allow {
+ if lint_name.as_str() == "restriction" && name != sym::allow {
span_lint_and_help(
cx,
BLANKET_CLIPPY_RESTRICTION_LINTS,
}
}
+fn check_lint_reason(cx: &LateContext<'_>, name: Symbol, items: &[NestedMetaItem], attr: &'_ Attribute) {
+ // Check for the feature
+ if !cx.tcx.sess.features_untracked().lint_reasons {
+ return;
+ }
+
+ // Check if the reason is present
+ if let Some(item) = items.last().and_then(NestedMetaItem::meta_item)
+ && let MetaItemKind::NameValue(_) = &item.kind
+ && item.path == sym::reason
+ {
+ return;
+ }
+
+ span_lint_and_help(
+ cx,
+ ALLOW_ATTRIBUTES_WITHOUT_REASON,
+ attr.span,
+ &format!("`{}` attribute without specifying a reason", name.as_str()),
+ None,
+ "try adding a reason at the end with `, reason = \"..\"`",
+ );
+}
+
fn is_relevant_item(cx: &LateContext<'_>, item: &Item<'_>) -> bool {
if let ItemKind::Fn(_, _, eid) = item.kind {
is_relevant_expr(cx, cx.tcx.typeck_body(eid), &cx.tcx.hir().body(eid).value)
}
fn is_relevant_expr(cx: &LateContext<'_>, typeck_results: &ty::TypeckResults<'_>, expr: &Expr<'_>) -> bool {
+ if macro_backtrace(expr.span).last().map_or(false, |macro_call| {
+ is_panic(cx, macro_call.def_id) || cx.tcx.item_name(macro_call.def_id) == sym::unreachable
+ }) {
+ return false;
+ }
match &expr.kind {
ExprKind::Block(block, _) => is_relevant_block(cx, typeck_results, block),
ExprKind::Ret(Some(e)) => is_relevant_expr(cx, typeck_results, e),
ExprKind::Ret(None) | ExprKind::Break(_, None) => false,
- ExprKind::Call(path_expr, _) => {
- if let ExprKind::Path(qpath) = &path_expr.kind {
- typeck_results
- .qpath_res(qpath, path_expr.hir_id)
- .opt_def_id()
- .map_or(true, |fun_id| !match_panic_def_id(cx, fun_id))
- } else {
- true
- }
- },
_ => true,
}
}
fn check_semver(cx: &LateContext<'_>, span: Span, lit: &Lit) {
if let LitKind::Str(is, _) = lit.kind {
- if Version::parse(&is.as_str()).is_ok() {
+ if Version::parse(is.as_str()).is_ok() {
return;
}
}
}
}
-declare_lint_pass!(EarlyAttributes => [
+pub struct EarlyAttributes {
+ pub msrv: Option<RustcVersion>,
+}
+
+impl_lint_pass!(EarlyAttributes => [
DEPRECATED_CFG_ATTR,
MISMATCHED_TARGET_OS,
EMPTY_LINE_AFTER_OUTER_ATTR,
}
fn check_attribute(&mut self, cx: &EarlyContext<'_>, attr: &Attribute) {
- check_deprecated_cfg_attr(cx, attr);
+ check_deprecated_cfg_attr(cx, attr, self.msrv);
check_mismatched_target_os(cx, attr);
}
+
+ extract_msrv_attr!(EarlyContext);
}
fn check_empty_line_after_outer_attr(cx: &EarlyContext<'_>, item: &rustc_ast::Item) {
return;
}
- let begin_of_attr_to_item = Span::new(attr.span.lo(), item.span.lo(), item.span.ctxt());
- let end_of_attr_to_item = Span::new(attr.span.hi(), item.span.lo(), item.span.ctxt());
+ let begin_of_attr_to_item = Span::new(attr.span.lo(), item.span.lo(), item.span.ctxt(), item.span.parent());
+ let end_of_attr_to_item = Span::new(attr.span.hi(), item.span.lo(), item.span.ctxt(), item.span.parent());
if let Some(snippet) = snippet_opt(cx, end_of_attr_to_item) {
let lines = snippet.split('\n').collect::<Vec<_>>();
}
}
-fn check_deprecated_cfg_attr(cx: &EarlyContext<'_>, attr: &Attribute) {
+fn check_deprecated_cfg_attr(cx: &EarlyContext<'_>, attr: &Attribute, msrv: Option<RustcVersion>) {
if_chain! {
+ if meets_msrv(msrv.as_ref(), &msrvs::TOOL_ATTRIBUTES);
// check cfg_attr
if attr.has_name(sym::cfg_attr);
if let Some(items) = attr.meta_item_list();
skip_item.path.segments.last().expect("empty path in attribute").ident.name == sym::skip;
// Only lint outer attributes, because custom inner attributes are unstable
// Tracking issue: https://github.com/rust-lang/rust/issues/54726
- if let AttrStyle::Outer = attr.style;
+ if attr.style == AttrStyle::Outer;
then {
span_lint_and_sugg(
cx,
MetaItemKind::Word => {
if_chain! {
if let Some(ident) = meta.ident();
- if let Some(os) = find_os(&*ident.name.as_str());
+ if let Some(os) = find_os(ident.name.as_str());
then {
mismatched.push((os, ident.span));
}
}
fn is_lint_level(symbol: Symbol) -> bool {
- matches!(symbol, sym::allow | sym::warn | sym::deny | sym::forbid)
+ matches!(symbol, sym::allow | sym::expect | sym::warn | sym::deny | sym::forbid)
}
projects / rustc.git / blobdiff