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Merge commit 'c1664c50b2' into clippyup

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This commit is contained in:
flip1995 2020-12-06 15:01:03 +01:00
parent 3be53bc45a
commit 8eca423ea1
139 changed files with 4334 additions and 576 deletions
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2
clippy_lints/src/attrs.rs
View file

@ -5,7 +5,6 @@ use crate::utils::{
span_lint_and_sugg, span_lint_and_then, without_block_comments,
};
use if_chain::if_chain;
use rustc_span::lev_distance::find_best_match_for_name;
use rustc_ast::{AttrKind, AttrStyle, Attribute, Lit, LitKind, MetaItemKind, NestedMetaItem};
use rustc_errors::Applicability;
use rustc_hir::{
@ -15,6 +14,7 @@ use rustc_lint::{CheckLintNameResult, EarlyContext, EarlyLintPass, LateContext,
use rustc_middle::lint::in_external_macro;
use rustc_middle::ty;
use rustc_session::{declare_lint_pass, declare_tool_lint};
use rustc_span::lev_distance::find_best_match_for_name;
use rustc_span::source_map::Span;
use rustc_span::sym;
use rustc_span::symbol::{Symbol, SymbolStr};

172
clippy_lints/src/collapsible_match.rs Normal file
View file

@ -0,0 +1,172 @@
use crate::utils::visitors::LocalUsedVisitor;
use crate::utils::{span_lint_and_then, SpanlessEq};
use if_chain::if_chain;
use rustc_hir::def::{CtorKind, CtorOf, DefKind, Res};
use rustc_hir::{Arm, Expr, ExprKind, Guard, HirId, Pat, PatKind, QPath, StmtKind};
use rustc_lint::{LateContext, LateLintPass};
use rustc_middle::ty::{DefIdTree, TyCtxt};
use rustc_session::{declare_lint_pass, declare_tool_lint};
use rustc_span::{MultiSpan, Span};
declare_clippy_lint! {
/// **What it does:** Finds nested `match` or `if let` expressions where the patterns may be "collapsed" together
/// without adding any branches.
///
/// Note that this lint is not intended to find _all_ cases where nested match patterns can be merged, but only
/// cases where merging would most likely make the code more readable.
///
/// **Why is this bad?** It is unnecessarily verbose and complex.
///
/// **Known problems:** None.
///
/// **Example:**
///
/// ```rust
/// fn func(opt: Option<Result<u64, String>>) {
/// let n = match opt {
/// Some(n) => match n {
/// Ok(n) => n,
/// _ => return,
/// }
/// None => return,
/// };
/// }
/// ```
/// Use instead:
/// ```rust
/// fn func(opt: Option<Result<u64, String>>) {
/// let n = match opt {
/// Some(Ok(n)) => n,
/// _ => return,
/// };
/// }
/// ```
pub COLLAPSIBLE_MATCH,
style,
"Nested `match` or `if let` expressions where the patterns may be \"collapsed\" together."
}
declare_lint_pass!(CollapsibleMatch => [COLLAPSIBLE_MATCH]);
impl<'tcx> LateLintPass<'tcx> for CollapsibleMatch {
fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &Expr<'tcx>) {
if let ExprKind::Match(_expr, arms, _source) = expr.kind {
if let Some(wild_arm) = arms.iter().rfind(|arm| arm_is_wild_like(arm, cx.tcx)) {
for arm in arms {
check_arm(arm, wild_arm, cx);
}
}
}
}
}
fn check_arm(arm: &Arm<'_>, wild_outer_arm: &Arm<'_>, cx: &LateContext<'_>) {
if_chain! {
let expr = strip_singleton_blocks(arm.body);
if let ExprKind::Match(expr_in, arms_inner, _) = expr.kind;
// the outer arm pattern and the inner match
if expr_in.span.ctxt() == arm.pat.span.ctxt();
// there must be no more than two arms in the inner match for this lint
if arms_inner.len() == 2;
// no if guards on the inner match
if arms_inner.iter().all(|arm| arm.guard.is_none());
// match expression must be a local binding
// match <local> { .. }
if let ExprKind::Path(QPath::Resolved(None, path)) = expr_in.kind;
if let Res::Local(binding_id) = path.res;
// one of the branches must be "wild-like"
if let Some(wild_inner_arm_idx) = arms_inner.iter().rposition(|arm_inner| arm_is_wild_like(arm_inner, cx.tcx));
let (wild_inner_arm, non_wild_inner_arm) =
(&arms_inner[wild_inner_arm_idx], &arms_inner[1 - wild_inner_arm_idx]);
if !pat_contains_or(non_wild_inner_arm.pat);
// the binding must come from the pattern of the containing match arm
// ..<local>.. => match <local> { .. }
if let Some(binding_span) = find_pat_binding(arm.pat, binding_id);
// the "wild-like" branches must be equal
if SpanlessEq::new(cx).eq_expr(wild_inner_arm.body, wild_outer_arm.body);
// the binding must not be used in the if guard
if !matches!(arm.guard, Some(Guard::If(guard)) if LocalUsedVisitor::new(binding_id).check_expr(guard));
// ...or anywhere in the inner match
if !arms_inner.iter().any(|arm| LocalUsedVisitor::new(binding_id).check_arm(arm));
then {
span_lint_and_then(
cx,
COLLAPSIBLE_MATCH,
expr.span,
"Unnecessary nested match",
|diag| {
let mut help_span = MultiSpan::from_spans(vec![binding_span, non_wild_inner_arm.pat.span]);
help_span.push_span_label(binding_span, "Replace this binding".into());
help_span.push_span_label(non_wild_inner_arm.pat.span, "with this pattern".into());
diag.span_help(help_span, "The outer pattern can be modified to include the inner pattern.");
},
);
}
}
}
fn strip_singleton_blocks<'hir>(mut expr: &'hir Expr<'hir>) -> &'hir Expr<'hir> {
while let ExprKind::Block(block, _) = expr.kind {
match (block.stmts, block.expr) {
([stmt], None) => match stmt.kind {
StmtKind::Expr(e) | StmtKind::Semi(e) => expr = e,
_ => break,
},
([], Some(e)) => expr = e,
_ => break,
}
}
expr
}
/// A "wild-like" pattern is wild ("_") or `None`.
/// For this lint to apply, both the outer and inner match expressions
/// must have "wild-like" branches that can be combined.
fn arm_is_wild_like(arm: &Arm<'_>, tcx: TyCtxt<'_>) -> bool {
if arm.guard.is_some() {
return false;
}
match arm.pat.kind {
PatKind::Binding(..) | PatKind::Wild => true,
PatKind::Path(QPath::Resolved(None, path)) if is_none_ctor(path.res, tcx) => true,
_ => false,
}
}
fn find_pat_binding(pat: &Pat<'_>, hir_id: HirId) -> Option<Span> {
let mut span = None;
pat.walk_short(|p| match &p.kind {
// ignore OR patterns
PatKind::Or(_) => false,
PatKind::Binding(_bm, _, _ident, _) => {
let found = p.hir_id == hir_id;
if found {
span = Some(p.span);
}
!found
},
_ => true,
});
span
}
fn pat_contains_or(pat: &Pat<'_>) -> bool {
let mut result = false;
pat.walk(|p| {
let is_or = matches!(p.kind, PatKind::Or(_));
result |= is_or;
!is_or
});
result
}
fn is_none_ctor(res: Res, tcx: TyCtxt<'_>) -> bool {
if let Some(none_id) = tcx.lang_items().option_none_variant() {
if let Res::Def(DefKind::Ctor(CtorOf::Variant, CtorKind::Const), id) = res {
if let Some(variant_id) = tcx.parent(id) {
return variant_id == none_id;
}
}
}
false
}

3
clippy_lints/src/comparison_chain.rs
View file

@ -12,7 +12,8 @@ declare_clippy_lint! {
/// **Why is this bad?** `if` is not guaranteed to be exhaustive and conditionals can get
/// repetitive
///
/// **Known problems:** None.
/// **Known problems:** The match statement may be slower due to the compiler
/// not inlining the call to cmp. See issue #5354
///
/// **Example:**
/// ```rust,ignore

3
clippy_lints/src/default.rs
View file

@ -280,8 +280,7 @@ fn field_reassigned_by_stmt<'tcx>(this: &Stmt<'tcx>, binding_name: Symbol) -> Op
// only take assignments to fields where the left-hand side field is a field of
// the same binding as the previous statement
if let ExprKind::Field(ref binding, field_ident) = assign_lhs.kind;
if let ExprKind::Path(ref qpath) = binding.kind;
if let QPath::Resolved(_, path) = qpath;
if let ExprKind::Path(QPath::Resolved(_, path)) = binding.kind;
if let Some(second_binding_name) = path.segments.last();
if second_binding_name.ident.name == binding_name;
then {

20
clippy_lints/src/deprecated_lints.rs
View file

@ -51,26 +51,6 @@ declare_deprecated_lint! {
"`Vec::as_mut_slice` has been stabilized in 1.7"
}
declare_deprecated_lint! {
/// **What it does:** Nothing. This lint has been deprecated.
///
/// **Deprecation reason:** This used to check for `.to_string()` method calls on values
/// of type `&str`. This is not unidiomatic and with specialization coming, `to_string` could be
/// specialized to be as efficient as `to_owned`.
pub STR_TO_STRING,
"using `str::to_string` is common even today and specialization will likely happen soon"
}
declare_deprecated_lint! {
/// **What it does:** Nothing. This lint has been deprecated.
///
/// **Deprecation reason:** This used to check for `.to_string()` method calls on values
/// of type `String`. This is not unidiomatic and with specialization coming, `to_string` could be
/// specialized to be as efficient as `clone`.
pub STRING_TO_STRING,
"using `string::to_string` is common even today and specialization will likely happen soon"
}
declare_deprecated_lint! {
/// **What it does:** Nothing. This lint has been deprecated.
///

27
clippy_lints/src/eq_op.rs
View file

@ -1,10 +1,10 @@
use crate::utils::{
eq_expr_value, higher, implements_trait, in_macro, is_copy, is_expn_of, multispan_sugg, snippet, span_lint,
span_lint_and_then,
ast_utils::is_useless_with_eq_exprs, eq_expr_value, higher, implements_trait, in_macro, is_copy, is_expn_of,
multispan_sugg, snippet, span_lint, span_lint_and_then,
};
use if_chain::if_chain;
use rustc_errors::Applicability;
use rustc_hir::{BinOp, BinOpKind, BorrowKind, Expr, ExprKind, StmtKind};
use rustc_hir::{BinOpKind, BorrowKind, Expr, ExprKind, StmtKind};
use rustc_lint::{LateContext, LateLintPass};
use rustc_session::{declare_lint_pass, declare_tool_lint};
@ -102,7 +102,7 @@ impl<'tcx> LateLintPass<'tcx> for EqOp {
if macro_with_not_op(&left.kind) || macro_with_not_op(&right.kind) {
return;
}
if is_valid_operator(op) && eq_expr_value(cx, left, right) {
if is_useless_with_eq_exprs(higher::binop(op.node)) && eq_expr_value(cx, left, right) {
span_lint(
cx,
EQ_OP,
@ -245,22 +245,3 @@ impl<'tcx> LateLintPass<'tcx> for EqOp {
}
}
}
fn is_valid_operator(op: BinOp) -> bool {
matches!(
op.node,
BinOpKind::Sub
| BinOpKind::Div
| BinOpKind::Eq
| BinOpKind::Lt
| BinOpKind::Le
| BinOpKind::Gt
| BinOpKind::Ge
| BinOpKind::Ne
| BinOpKind::And
| BinOpKind::Or
| BinOpKind::BitXor
| BinOpKind::BitAnd
| BinOpKind::BitOr
)
}

3
clippy_lints/src/if_let_some_result.rs
View file

@ -41,8 +41,7 @@ declare_lint_pass!(OkIfLet => [IF_LET_SOME_RESULT]);
impl<'tcx> LateLintPass<'tcx> for OkIfLet {
fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
if_chain! { //begin checking variables
if let ExprKind::Match(ref op, ref body, source) = expr.kind; //test if expr is a match
if let MatchSource::IfLetDesugar { .. } = source; //test if it is an If Let
if let ExprKind::Match(ref op, ref body, MatchSource::IfLetDesugar { .. }) = expr.kind; //test if expr is if let
if let ExprKind::MethodCall(_, ok_span, ref result_types, _) = op.kind; //check is expr.ok() has type Result<T,E>.ok(, _)
if let PatKind::TupleStruct(QPath::Resolved(_, ref x), ref y, _) = body[0].pat.kind; //get operation
if method_chain_args(op, &["ok"]).is_some(); //test to see if using ok() methoduse std::marker::Sized;

3
clippy_lints/src/implicit_return.rs
View file

@ -68,8 +68,7 @@ fn expr_match(cx: &LateContext<'_>, expr: &Expr<'_>) {
if_chain! {
if let StmtKind::Semi(expr, ..) = &stmt.kind;
// make sure it's a break, otherwise we want to skip
if let ExprKind::Break(.., break_expr) = &expr.kind;
if let Some(break_expr) = break_expr;
if let ExprKind::Break(.., Some(break_expr)) = &expr.kind;
then {
lint(cx, expr.span, break_expr.span, LINT_BREAK);
}

3
clippy_lints/src/implicit_saturating_sub.rs
View file

@ -59,8 +59,7 @@ impl<'tcx> LateLintPass<'tcx> for ImplicitSaturatingSub {
if let Some(target) = subtracts_one(cx, e);
// Extracting out the variable name
if let ExprKind::Path(ref assign_path) = target.kind;
if let QPath::Resolved(_, ref ares_path) = assign_path;
if let ExprKind::Path(QPath::Resolved(_, ref ares_path)) = target.kind;
then {
// Handle symmetric conditions in the if statement

4
clippy_lints/src/items_after_statements.rs
View file

@ -58,12 +58,12 @@ impl EarlyLintPass for ItemsAfterStatements {
return;
}
// skip initial items
// skip initial items and trailing semicolons
let stmts = item
.stmts
.iter()
.map(|stmt| &stmt.kind)
.skip_while(|s| matches!(**s, StmtKind::Item(..)));
.skip_while(|s| matches!(**s, StmtKind::Item(..) | StmtKind::Empty));
// lint on all further items
for stmt in stmts {

3
clippy_lints/src/large_const_arrays.rs
View file

@ -52,8 +52,7 @@ impl<'tcx> LateLintPass<'tcx> for LargeConstArrays {
if let ItemKind::Const(hir_ty, _) = &item.kind;
let ty = hir_ty_to_ty(cx.tcx, hir_ty);
if let ty::Array(element_type, cst) = ty.kind();
if let ConstKind::Value(val) = cst.val;
if let ConstValue::Scalar(element_count) = val;
if let ConstKind::Value(ConstValue::Scalar(element_count)) = cst.val;
if let Ok(element_count) = element_count.to_machine_usize(&cx.tcx);
if let Ok(element_size) = cx.layout_of(element_type).map(|l| l.size.bytes());
if self.maximum_allowed_size < element_count * element_size;

3
clippy_lints/src/large_stack_arrays.rs
View file

@ -43,8 +43,7 @@ impl<'tcx> LateLintPass<'tcx> for LargeStackArrays {
if_chain! {
if let ExprKind::Repeat(_, _) = expr.kind;
if let ty::Array(element_type, cst) = cx.typeck_results().expr_ty(expr).kind();
if let ConstKind::Value(val) = cst.val;
if let ConstValue::Scalar(element_count) = val;
if let ConstKind::Value(ConstValue::Scalar(element_count)) = cst.val;
if let Ok(element_count) = element_count.to_machine_usize(&cx.tcx);
if let Ok(element_size) = cx.layout_of(element_type).map(|l| l.size.bytes());
if self.maximum_allowed_size < element_count * element_size;

53
clippy_lints/src/let_if_seq.rs
View file

@ -1,12 +1,11 @@
use crate::utils::visitors::LocalUsedVisitor;
use crate::utils::{higher, qpath_res, snippet, span_lint_and_then};
use if_chain::if_chain;
use rustc_errors::Applicability;
use rustc_hir as hir;
use rustc_hir::def::Res;
use rustc_hir::intravisit;
use rustc_hir::BindingAnnotation;
use rustc_lint::{LateContext, LateLintPass};
use rustc_middle::hir::map::Map;
use rustc_session::{declare_lint_pass, declare_tool_lint};
declare_clippy_lint! {
@ -66,10 +65,10 @@ impl<'tcx> LateLintPass<'tcx> for LetIfSeq {
if let hir::PatKind::Binding(mode, canonical_id, ident, None) = local.pat.kind;
if let hir::StmtKind::Expr(ref if_) = expr.kind;
if let Some((ref cond, ref then, ref else_)) = higher::if_block(&if_);
if !used_in_expr(cx, canonical_id, cond);
if !LocalUsedVisitor::new(canonical_id).check_expr(cond);
if let hir::ExprKind::Block(ref then, _) = then.kind;
if let Some(value) = check_assign(cx, canonical_id, &*then);
if !used_in_expr(cx, canonical_id, value);
if !LocalUsedVisitor::new(canonical_id).check_expr(value);
then {
let span = stmt.span.to(if_.span);
@ -136,32 +135,6 @@ impl<'tcx> LateLintPass<'tcx> for LetIfSeq {
}
}
struct UsedVisitor<'a, 'tcx> {
cx: &'a LateContext<'tcx>,
id: hir::HirId,
used: bool,
}
impl<'a, 'tcx> intravisit::Visitor<'tcx> for UsedVisitor<'a, 'tcx> {
type Map = Map<'tcx>;
fn visit_expr(&mut self, expr: &'tcx hir::Expr<'_>) {
if_chain! {
if let hir::ExprKind::Path(ref qpath) = expr.kind;
if let Res::Local(local_id) = qpath_res(self.cx, qpath, expr.hir_id);
if self.id == local_id;
then {
self.used = true;
return;
}
}
intravisit::walk_expr(self, expr);
}
fn nested_visit_map(&mut self) -> intravisit::NestedVisitorMap<Self::Map> {
intravisit::NestedVisitorMap::None
}
}
fn check_assign<'tcx>(
cx: &LateContext<'tcx>,
decl: hir::HirId,
@ -176,18 +149,10 @@ fn check_assign<'tcx>(
if let Res::Local(local_id) = qpath_res(cx, qpath, var.hir_id);
if decl == local_id;
then {
let mut v = UsedVisitor {
cx,
id: decl,
used: false,
};
let mut v = LocalUsedVisitor::new(decl);
for s in block.stmts.iter().take(block.stmts.len()-1) {
intravisit::walk_stmt(&mut v, s);
if v.used {
return None;
}
if block.stmts.iter().take(block.stmts.len()-1).any(|stmt| v.check_stmt(stmt)) {
return None;
}
return Some(value);
@ -196,9 +161,3 @@ fn check_assign<'tcx>(
None
}
fn used_in_expr<'tcx>(cx: &LateContext<'tcx>, id: hir::HirId, expr: &'tcx hir::Expr<'_>) -> bool {
let mut v = UsedVisitor { cx, id, used: false };
intravisit::walk_expr(&mut v, expr);
v.used
}

113
clippy_lints/src/lib.rs
View file

@ -44,6 +44,7 @@ extern crate rustc_target;
extern crate rustc_trait_selection;
extern crate rustc_typeck;
use crate::utils::parse_msrv;
use rustc_data_structures::fx::FxHashSet;
use rustc_lint::LintId;
use rustc_session::Session;
@ -171,6 +172,7 @@ mod cargo_common_metadata;
mod checked_conversions;
mod cognitive_complexity;
mod collapsible_if;
mod collapsible_match;
mod comparison_chain;
mod copies;
mod copy_iterator;
@ -304,9 +306,11 @@ mod self_assignment;
mod serde_api;
mod shadow;
mod single_component_path_imports;
mod size_of_in_element_count;
mod slow_vector_initialization;
mod stable_sort_primitive;
mod strings;
mod suspicious_operation_groupings;
mod suspicious_trait_impl;
mod swap;
mod tabs_in_doc_comments;
@ -440,14 +444,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
"clippy::unstable_as_mut_slice",
"`Vec::as_mut_slice` has been stabilized in 1.7",
);
store.register_removed(
"clippy::str_to_string",
"using `str::to_string` is common even today and specialization will likely happen soon",
);
store.register_removed(
"clippy::string_to_string",
"using `string::to_string` is common even today and specialization will likely happen soon",
);
store.register_removed(
"clippy::misaligned_transmute",
"this lint has been split into cast_ptr_alignment and transmute_ptr_to_ptr",
@ -504,6 +500,24 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
// begin register lints, do not remove this comment, it’s used in `update_lints`
store.register_lints(&[
#[cfg(feature = "internal-lints")]
&utils::internal_lints::CLIPPY_LINTS_INTERNAL,
#[cfg(feature = "internal-lints")]
&utils::internal_lints::COLLAPSIBLE_SPAN_LINT_CALLS,
#[cfg(feature = "internal-lints")]
&utils::internal_lints::COMPILER_LINT_FUNCTIONS,
#[cfg(feature = "internal-lints")]
&utils::internal_lints::DEFAULT_LINT,
#[cfg(feature = "internal-lints")]
&utils::internal_lints::INVALID_PATHS,
#[cfg(feature = "internal-lints")]
&utils::internal_lints::LINT_WITHOUT_LINT_PASS,
#[cfg(feature = "internal-lints")]
&utils::internal_lints::MATCH_TYPE_ON_DIAGNOSTIC_ITEM,
#[cfg(feature = "internal-lints")]
&utils::internal_lints::OUTER_EXPN_EXPN_DATA,
#[cfg(feature = "internal-lints")]
&utils::internal_lints::PRODUCE_ICE,
&approx_const::APPROX_CONSTANT,
&arithmetic::FLOAT_ARITHMETIC,
&arithmetic::INTEGER_ARITHMETIC,
@ -537,6 +551,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
&checked_conversions::CHECKED_CONVERSIONS,
&cognitive_complexity::COGNITIVE_COMPLEXITY,
&collapsible_if::COLLAPSIBLE_IF,
&collapsible_match::COLLAPSIBLE_MATCH,
&comparison_chain::COMPARISON_CHAIN,
&copies::IFS_SAME_COND,
&copies::IF_SAME_THEN_ELSE,
@ -833,12 +848,16 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
&shadow::SHADOW_SAME,
&shadow::SHADOW_UNRELATED,
&single_component_path_imports::SINGLE_COMPONENT_PATH_IMPORTS,
&size_of_in_element_count::SIZE_OF_IN_ELEMENT_COUNT,
&slow_vector_initialization::SLOW_VECTOR_INITIALIZATION,
&stable_sort_primitive::STABLE_SORT_PRIMITIVE,
&strings::STRING_ADD,
&strings::STRING_ADD_ASSIGN,
&strings::STRING_FROM_UTF8_AS_BYTES,
&strings::STRING_LIT_AS_BYTES,
&strings::STRING_TO_STRING,
&strings::STR_TO_STRING,
&suspicious_operation_groupings::SUSPICIOUS_OPERATION_GROUPINGS,
&suspicious_trait_impl::SUSPICIOUS_ARITHMETIC_IMPL,
&suspicious_trait_impl::SUSPICIOUS_OP_ASSIGN_IMPL,
&swap::ALMOST_SWAPPED,
@ -907,15 +926,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
&unwrap_in_result::UNWRAP_IN_RESULT,
&use_self::USE_SELF,
&useless_conversion::USELESS_CONVERSION,
&utils::internal_lints::CLIPPY_LINTS_INTERNAL,
&utils::internal_lints::COLLAPSIBLE_SPAN_LINT_CALLS,
&utils::internal_lints::COMPILER_LINT_FUNCTIONS,
&utils::internal_lints::DEFAULT_LINT,
&utils::internal_lints::INVALID_PATHS,
&utils::internal_lints::LINT_WITHOUT_LINT_PASS,
&utils::internal_lints::MATCH_TYPE_ON_DIAGNOSTIC_ITEM,
&utils::internal_lints::OUTER_EXPN_EXPN_DATA,
&utils::internal_lints::PRODUCE_ICE,
&vec::USELESS_VEC,
&vec_resize_to_zero::VEC_RESIZE_TO_ZERO,
&verbose_file_reads::VERBOSE_FILE_READS,
@ -934,14 +944,22 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
]);
// end register lints, do not remove this comment, it’s used in `update_lints`
// all the internal lints
#[cfg(feature = "internal-lints")]
{
store.register_early_pass(|| box utils::internal_lints::ClippyLintsInternal);
store.register_early_pass(|| box utils::internal_lints::ProduceIce);
store.register_late_pass(|| box utils::inspector::DeepCodeInspector);
store.register_late_pass(|| box utils::internal_lints::CollapsibleCalls);
store.register_late_pass(|| box utils::internal_lints::CompilerLintFunctions::new());
store.register_late_pass(|| box utils::internal_lints::InvalidPaths);
store.register_late_pass(|| box utils::internal_lints::LintWithoutLintPass::default());
store.register_late_pass(|| box utils::internal_lints::MatchTypeOnDiagItem);
store.register_late_pass(|| box utils::internal_lints::OuterExpnDataPass);
}
store.register_late_pass(|| box utils::author::Author);
store.register_late_pass(|| box await_holding_invalid::AwaitHolding);
store.register_late_pass(|| box serde_api::SerdeAPI);
store.register_late_pass(|| box utils::internal_lints::CompilerLintFunctions::new());
store.register_late_pass(|| box utils::internal_lints::LintWithoutLintPass::default());
store.register_late_pass(|| box utils::internal_lints::OuterExpnDataPass);
store.register_late_pass(|| box utils::internal_lints::InvalidPaths);
store.register_late_pass(|| box utils::inspector::DeepCodeInspector);
store.register_late_pass(|| box utils::author::Author);
let vec_box_size_threshold = conf.vec_box_size_threshold;
store.register_late_pass(move || box types::Types::new(vec_box_size_threshold));
store.register_late_pass(|| box booleans::NonminimalBool);
@ -964,12 +982,25 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
store.register_late_pass(|| box len_zero::LenZero);
store.register_late_pass(|| box attrs::Attributes);
store.register_late_pass(|| box blocks_in_if_conditions::BlocksInIfConditions);
store.register_late_pass(|| box collapsible_match::CollapsibleMatch);
store.register_late_pass(|| box unicode::Unicode);
store.register_late_pass(|| box unit_return_expecting_ord::UnitReturnExpectingOrd);
store.register_late_pass(|| box strings::StringAdd);
store.register_late_pass(|| box implicit_return::ImplicitReturn);
store.register_late_pass(|| box implicit_saturating_sub::ImplicitSaturatingSub);
store.register_late_pass(|| box methods::Methods);
let msrv = conf.msrv.as_ref().and_then(|s| {
parse_msrv(s, None, None).or_else(|| {
sess.err(&format!("error reading Clippy's configuration file. `{}` is not a valid Rust version", s));
None
})
});
store.register_late_pass(move || box methods::Methods::new(msrv));
store.register_late_pass(move || box matches::Matches::new(msrv));
store.register_early_pass(move || box manual_non_exhaustive::ManualNonExhaustive::new(msrv));
store.register_late_pass(move || box manual_strip::ManualStrip::new(msrv));
store.register_late_pass(|| box size_of_in_element_count::SizeOfInElementCount);
store.register_late_pass(|| box map_clone::MapClone);
store.register_late_pass(|| box map_err_ignore::MapErrIgnore);
store.register_late_pass(|| box shadow::Shadow);
@ -983,7 +1014,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
store.register_late_pass(|| box types::Casts);
let type_complexity_threshold = conf.type_complexity_threshold;
store.register_late_pass(move || box types::TypeComplexity::new(type_complexity_threshold));
store.register_late_pass(|| box matches::Matches::default());
store.register_late_pass(|| box minmax::MinMaxPass);
store.register_late_pass(|| box open_options::OpenOptions);
store.register_late_pass(|| box zero_div_zero::ZeroDiv);
@ -1057,6 +1087,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
store.register_late_pass(|| box types::UnitArg);
store.register_late_pass(|| box double_comparison::DoubleComparisons);
store.register_late_pass(|| box question_mark::QuestionMark);
store.register_early_pass(|| box suspicious_operation_groupings::SuspiciousOperationGroupings);
store.register_late_pass(|| box suspicious_trait_impl::SuspiciousImpl);
store.register_late_pass(|| box map_unit_fn::MapUnit);
store.register_late_pass(|| box inherent_impl::MultipleInherentImpl::default());
@ -1107,10 +1138,10 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
store.register_late_pass(|| box cargo_common_metadata::CargoCommonMetadata);
store.register_late_pass(|| box multiple_crate_versions::MultipleCrateVersions);
store.register_late_pass(|| box wildcard_dependencies::WildcardDependencies);
store.register_early_pass(|| box literal_representation::LiteralDigitGrouping);
let literal_representation_lint_fraction_readability = conf.unreadable_literal_lint_fractions;
store.register_early_pass(move || box literal_representation::LiteralDigitGrouping::new(literal_representation_lint_fraction_readability));
let literal_representation_threshold = conf.literal_representation_threshold;
store.register_early_pass(move || box literal_representation::DecimalLiteralRepresentation::new(literal_representation_threshold));
store.register_early_pass(|| box utils::internal_lints::ClippyLintsInternal);
let enum_variant_name_threshold = conf.enum_variant_name_threshold;
store.register_early_pass(move || box enum_variants::EnumVariantNames::new(enum_variant_name_threshold));
store.register_early_pass(|| box tabs_in_doc_comments::TabsInDocComments);
@ -1124,7 +1155,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
store.register_late_pass(move || box large_const_arrays::LargeConstArrays::new(array_size_threshold));
store.register_late_pass(|| box floating_point_arithmetic::FloatingPointArithmetic);
store.register_early_pass(|| box as_conversions::AsConversions);
store.register_early_pass(|| box utils::internal_lints::ProduceIce);
store.register_late_pass(|| box let_underscore::LetUnderscore);
store.register_late_pass(|| box atomic_ordering::AtomicOrdering);
store.register_early_pass(|| box single_component_path_imports::SingleComponentPathImports);
@ -1140,16 +1170,13 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
store.register_late_pass(|| box dereference::Dereferencing);
store.register_late_pass(|| box option_if_let_else::OptionIfLetElse);
store.register_late_pass(|| box future_not_send::FutureNotSend);
store.register_late_pass(|| box utils::internal_lints::CollapsibleCalls);
store.register_late_pass(|| box if_let_mutex::IfLetMutex);
store.register_late_pass(|| box mut_mutex_lock::MutMutexLock);
store.register_late_pass(|| box match_on_vec_items::MatchOnVecItems);
store.register_early_pass(|| box manual_non_exhaustive::ManualNonExhaustive);
store.register_late_pass(|| box manual_async_fn::ManualAsyncFn);
store.register_early_pass(|| box redundant_field_names::RedundantFieldNames);
store.register_late_pass(|| box vec_resize_to_zero::VecResizeToZero);
store.register_late_pass(|| box panic_in_result_fn::PanicInResultFn);
let single_char_binding_names_threshold = conf.single_char_binding_names_threshold;
store.register_early_pass(move || box non_expressive_names::NonExpressiveNames {
single_char_binding_names_threshold,
@ -1166,14 +1193,13 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
store.register_late_pass(|| box manual_ok_or::ManualOkOr);
store.register_late_pass(|| box float_equality_without_abs::FloatEqualityWithoutAbs);
store.register_late_pass(|| box async_yields_async::AsyncYieldsAsync);
store.register_late_pass(|| box manual_strip::ManualStrip);
store.register_late_pass(|| box utils::internal_lints::MatchTypeOnDiagItem);
let disallowed_methods = conf.disallowed_methods.iter().cloned().collect::<FxHashSet<_>>();
store.register_late_pass(move || box disallowed_method::DisallowedMethod::new(&disallowed_methods));
store.register_early_pass(|| box asm_syntax::InlineAsmX86AttSyntax);
store.register_early_pass(|| box asm_syntax::InlineAsmX86IntelSyntax);
store.register_late_pass(|| box undropped_manually_drops::UndroppedManuallyDrops);
store.register_late_pass(|| box strings::StrToString);
store.register_late_pass(|| box strings::StringToString);
store.register_group(true, "clippy::restriction", Some("clippy_restriction"), vec![
LintId::of(&arithmetic::FLOAT_ARITHMETIC),
@ -1192,6 +1218,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
LintId::of(&integer_division::INTEGER_DIVISION),
LintId::of(&let_underscore::LET_UNDERSCORE_MUST_USE),
LintId::of(&literal_representation::DECIMAL_LITERAL_REPRESENTATION),
LintId::of(&map_err_ignore::MAP_ERR_IGNORE),
LintId::of(&matches::REST_PAT_IN_FULLY_BOUND_STRUCTS),
LintId::of(&matches::WILDCARD_ENUM_MATCH_ARM),
LintId::of(&mem_forget::MEM_FORGET),
@ -1215,6 +1242,8 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
LintId::of(&shadow::SHADOW_REUSE),
LintId::of(&shadow::SHADOW_SAME),
LintId::of(&strings::STRING_ADD),
LintId::of(&strings::STRING_TO_STRING),
LintId::of(&strings::STR_TO_STRING),
LintId::of(&types::RC_BUFFER),
LintId::of(&unwrap_in_result::UNWRAP_IN_RESULT),
LintId::of(&verbose_file_reads::VERBOSE_FILE_READS),
@ -1256,7 +1285,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
LintId::of(&loops::EXPLICIT_ITER_LOOP),
LintId::of(&macro_use::MACRO_USE_IMPORTS),
LintId::of(&manual_ok_or::MANUAL_OK_OR),
LintId::of(&map_err_ignore::MAP_ERR_IGNORE),
LintId::of(&match_on_vec_items::MATCH_ON_VEC_ITEMS),
LintId::of(&matches::MATCH_BOOL),
LintId::of(&matches::MATCH_SAME_ARMS),
@ -1304,6 +1332,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
LintId::of(&wildcard_imports::WILDCARD_IMPORTS),
]);
#[cfg(feature = "internal-lints")]
store.register_group(true, "clippy::internal", Some("clippy_internal"), vec![
LintId::of(&utils::internal_lints::CLIPPY_LINTS_INTERNAL),
LintId::of(&utils::internal_lints::COLLAPSIBLE_SPAN_LINT_CALLS),
@ -1337,6 +1366,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
LintId::of(&booleans::NONMINIMAL_BOOL),
LintId::of(&bytecount::NAIVE_BYTECOUNT),
LintId::of(&collapsible_if::COLLAPSIBLE_IF),
LintId::of(&collapsible_match::COLLAPSIBLE_MATCH),
LintId::of(&comparison_chain::COMPARISON_CHAIN),
LintId::of(&copies::IFS_SAME_COND),
LintId::of(&copies::IF_SAME_THEN_ELSE),
@ -1533,9 +1563,11 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
LintId::of(&self_assignment::SELF_ASSIGNMENT),
LintId::of(&serde_api::SERDE_API_MISUSE),
LintId::of(&single_component_path_imports::SINGLE_COMPONENT_PATH_IMPORTS),
LintId::of(&size_of_in_element_count::SIZE_OF_IN_ELEMENT_COUNT),
LintId::of(&slow_vector_initialization::SLOW_VECTOR_INITIALIZATION),
LintId::of(&stable_sort_primitive::STABLE_SORT_PRIMITIVE),
LintId::of(&strings::STRING_FROM_UTF8_AS_BYTES),
LintId::of(&suspicious_operation_groupings::SUSPICIOUS_OPERATION_GROUPINGS),
LintId::of(&suspicious_trait_impl::SUSPICIOUS_ARITHMETIC_IMPL),
LintId::of(&suspicious_trait_impl::SUSPICIOUS_OP_ASSIGN_IMPL),
LintId::of(&swap::ALMOST_SWAPPED),
@ -1602,6 +1634,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
LintId::of(&blacklisted_name::BLACKLISTED_NAME),
LintId::of(&blocks_in_if_conditions::BLOCKS_IN_IF_CONDITIONS),
LintId::of(&collapsible_if::COLLAPSIBLE_IF),
LintId::of(&collapsible_match::COLLAPSIBLE_MATCH),
LintId::of(&comparison_chain::COMPARISON_CHAIN),
LintId::of(&default::FIELD_REASSIGN_WITH_DEFAULT),
LintId::of(&doc::MISSING_SAFETY_DOC),
@ -1687,6 +1720,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
LintId::of(&returns::LET_AND_RETURN),
LintId::of(&returns::NEEDLESS_RETURN),
LintId::of(&single_component_path_imports::SINGLE_COMPONENT_PATH_IMPORTS),
LintId::of(&suspicious_operation_groupings::SUSPICIOUS_OPERATION_GROUPINGS),
LintId::of(&tabs_in_doc_comments::TABS_IN_DOC_COMMENTS),
LintId::of(&to_digit_is_some::TO_DIGIT_IS_SOME),
LintId::of(&try_err::TRY_ERR),
@ -1839,6 +1873,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
LintId::of(&regex::INVALID_REGEX),
LintId::of(&self_assignment::SELF_ASSIGNMENT),
LintId::of(&serde_api::SERDE_API_MISUSE),
LintId::of(&size_of_in_element_count::SIZE_OF_IN_ELEMENT_COUNT),
LintId::of(&suspicious_trait_impl::SUSPICIOUS_ARITHMETIC_IMPL),
LintId::of(&suspicious_trait_impl::SUSPICIOUS_OP_ASSIGN_IMPL),
LintId::of(&swap::ALMOST_SWAPPED),
@ -1930,14 +1965,6 @@ fn register_removed_non_tool_lints(store: &mut rustc_lint::LintStore) {
"unstable_as_mut_slice",
"`Vec::as_mut_slice` has been stabilized in 1.7",
);
store.register_removed(
"str_to_string",
"using `str::to_string` is common even today and specialization will likely happen soon",
);
store.register_removed(
"string_to_string",
"using `string::to_string` is common even today and specialization will likely happen soon",
);
store.register_removed(
"misaligned_transmute",
"this lint has been split into cast_ptr_alignment and transmute_ptr_to_ptr",

37
clippy_lints/src/literal_representation.rs
View file

@ -11,7 +11,7 @@ use rustc_ast::ast::{Expr, ExprKind, Lit, LitKind};
use rustc_errors::Applicability;
use rustc_lint::{EarlyContext, EarlyLintPass, LintContext};
use rustc_middle::lint::in_external_macro;
use rustc_session::{declare_lint_pass, declare_tool_lint, impl_lint_pass};
use rustc_session::{declare_tool_lint, impl_lint_pass};
declare_clippy_lint! {
/// **What it does:** Warns if a long integral or floating-point constant does
@ -32,7 +32,7 @@ declare_clippy_lint! {
/// ```
pub UNREADABLE_LITERAL,
pedantic,
"long integer literal without underscores"
"long literal without underscores"
}
declare_clippy_lint! {
@ -208,7 +208,13 @@ impl WarningType {
}
}
declare_lint_pass!(LiteralDigitGrouping => [
#[allow(clippy::module_name_repetitions)]
#[derive(Copy, Clone)]
pub struct LiteralDigitGrouping {
lint_fraction_readability: bool,
}
impl_lint_pass!(LiteralDigitGrouping => [
UNREADABLE_LITERAL,
INCONSISTENT_DIGIT_GROUPING,
LARGE_DIGIT_GROUPS,
@ -223,7 +229,7 @@ impl EarlyLintPass for LiteralDigitGrouping {
}
if let ExprKind::Lit(ref lit) = expr.kind {
Self::check_lit(cx, lit)
self.check_lit(cx, lit)
}
}
}
@ -232,7 +238,13 @@ impl EarlyLintPass for LiteralDigitGrouping {
const UUID_GROUP_LENS: [usize; 5] = [8, 4, 4, 4, 12];
impl LiteralDigitGrouping {
fn check_lit(cx: &EarlyContext<'_>, lit: &Lit) {
pub fn new(lint_fraction_readability: bool) -> Self {
Self {
lint_fraction_readability,
}
}
fn check_lit(self, cx: &EarlyContext<'_>, lit: &Lit) {
if_chain! {
if let Some(src) = snippet_opt(cx, lit.span);
if let Some(mut num_lit) = NumericLiteral::from_lit(&src, &lit);
@ -247,9 +259,12 @@ impl LiteralDigitGrouping {
let result = (|| {
let integral_group_size = Self::get_group_size(num_lit.integer.split('_'), num_lit.radix)?;
let integral_group_size = Self::get_group_size(num_lit.integer.split('_'), num_lit.radix, true)?;
if let Some(fraction) = num_lit.fraction {
let fractional_group_size = Self::get_group_size(fraction.rsplit('_'), num_lit.radix)?;
let fractional_group_size = Self::get_group_size(
fraction.rsplit('_'),
num_lit.radix,
self.lint_fraction_readability)?;
let consistent = Self::parts_consistent(integral_group_size,
fractional_group_size,
@ -363,7 +378,11 @@ impl LiteralDigitGrouping {
/// Returns the size of the digit groups (or None if ungrouped) if successful,
/// otherwise returns a `WarningType` for linting.
fn get_group_size<'a>(groups: impl Iterator<Item = &'a str>, radix: Radix) -> Result<Option<usize>, WarningType> {
fn get_group_size<'a>(
groups: impl Iterator<Item = &'a str>,
radix: Radix,
lint_unreadable: bool,
) -> Result<Option<usize>, WarningType> {
let mut groups = groups.map(str::len);
let first = groups.next().expect("At least one group");
@ -380,7 +399,7 @@ impl LiteralDigitGrouping {
} else {
Ok(Some(second))
}
} else if first > 5 {
} else if first > 5 && lint_unreadable {
Err(WarningType::UnreadableLiteral)
} else {
Ok(None)

69
clippy_lints/src/loops.rs
View file

@ -2,6 +2,7 @@ use crate::consts::constant;
use crate::utils::paths;
use crate::utils::sugg::Sugg;
use crate::utils::usage::{is_unused, mutated_variables};
use crate::utils::visitors::LocalUsedVisitor;
use crate::utils::{
contains_name, get_enclosing_block, get_parent_expr, get_trait_def_id, has_iter_method, higher, implements_trait,
indent_of, is_in_panic_handler, is_integer_const, is_no_std_crate, is_refutable, is_type_diagnostic_item,
@ -1919,8 +1920,7 @@ fn check_for_single_element_loop<'tcx>(
if_chain! {
if let ExprKind::AddrOf(BorrowKind::Ref, _, ref arg_expr) = arg.kind;
if let PatKind::Binding(.., target, _) = pat.kind;
if let ExprKind::Array(ref arg_expr_list) = arg_expr.kind;
if let [arg_expression] = arg_expr_list;
if let ExprKind::Array([arg_expression]) = arg_expr.kind;
if let ExprKind::Path(ref list_item) = arg_expression.kind;
if let Some(list_item_name) = single_segment_path(list_item).map(|ps| ps.ident.name);
if let ExprKind::Block(ref block, _) = body.kind;
@ -2025,8 +2025,7 @@ fn check_for_mutability(cx: &LateContext<'_>, bound: &Expr<'_>) -> Option<HirId>
let node_str = cx.tcx.hir().get(hir_id);
if_chain! {
if let Node::Binding(pat) = node_str;
if let PatKind::Binding(bind_ann, ..) = pat.kind;
if let BindingAnnotation::Mutable = bind_ann;
if let PatKind::Binding(BindingAnnotation::Mutable, ..) = pat.kind;
then {
return Some(hir_id);
}
@ -2071,28 +2070,6 @@ fn pat_is_wild<'tcx>(pat: &'tcx PatKind<'_>, body: &'tcx Expr<'_>) -> bool {
}
}
struct LocalUsedVisitor<'a, 'tcx> {
cx: &'a LateContext<'tcx>,
local: HirId,
used: bool,
}
impl<'a, 'tcx> Visitor<'tcx> for LocalUsedVisitor<'a, 'tcx> {
type Map = Map<'tcx>;
fn visit_expr(&mut self, expr: &'tcx Expr<'_>) {
if same_var(self.cx, expr, self.local) {
self.used = true;
} else {
walk_expr(self, expr);
}
}
fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
NestedVisitorMap::None
}
}
struct VarVisitor<'a, 'tcx> {
/// context reference
cx: &'a LateContext<'tcx>,
@ -2126,11 +2103,7 @@ impl<'a, 'tcx> VarVisitor<'a, 'tcx> {
then {
let index_used_directly = same_var(self.cx, idx, self.var);
let indexed_indirectly = {
let mut used_visitor = LocalUsedVisitor {
cx: self.cx,
local: self.var,
used: false,
};
let mut used_visitor = LocalUsedVisitor::new(self.var);
walk_expr(&mut used_visitor, idx);
used_visitor.used
};
@ -2950,7 +2923,7 @@ fn check_needless_collect_indirect_usage<'tcx>(expr: &'tcx Expr<'_>, cx: &LateCo
for ref stmt in block.stmts {
if_chain! {
if let StmtKind::Local(
Local { pat: Pat { kind: PatKind::Binding(_, _, ident, .. ), .. },
Local { pat: Pat { hir_id: pat_id, kind: PatKind::Binding(_, _, ident, .. ), .. },
init: Some(ref init_expr), .. }
) = stmt.kind;
if let ExprKind::MethodCall(ref method_name, _, &[ref iter_source], ..) = init_expr.kind;
@ -2964,6 +2937,16 @@ fn check_needless_collect_indirect_usage<'tcx>(expr: &'tcx Expr<'_>, cx: &LateCo
if let Some(iter_calls) = detect_iter_and_into_iters(block, *ident);
if iter_calls.len() == 1;
then {
let mut used_count_visitor = UsedCountVisitor {
cx,
id: *pat_id,
count: 0,
};
walk_block(&mut used_count_visitor, block);
if used_count_visitor.count > 1 {
return;
}
// Suggest replacing iter_call with iter_replacement, and removing stmt
let iter_call = &iter_calls[0];
span_lint_and_then(
@ -3087,6 +3070,28 @@ impl<'tcx> Visitor<'tcx> for IterFunctionVisitor {
}
}
struct UsedCountVisitor<'a, 'tcx> {
cx: &'a LateContext<'tcx>,
id: HirId,
count: usize,
}
impl<'a, 'tcx> Visitor<'tcx> for UsedCountVisitor<'a, 'tcx> {
type Map = Map<'tcx>;
fn visit_expr(&mut self, expr: &'tcx Expr<'_>) {
if same_var(self.cx, expr, self.id) {
self.count += 1;
} else {
walk_expr(self, expr);
}
}
fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
NestedVisitorMap::OnlyBodies(self.cx.tcx.hir())
}
}
/// Detect the occurrences of calls to `iter` or `into_iter` for the
/// given identifier
fn detect_iter_and_into_iters<'tcx>(block: &'tcx Block<'tcx>, identifier: Ident) -> Option<Vec<IterFunction>> {

27
clippy_lints/src/manual_non_exhaustive.rs
View file

@ -1,12 +1,15 @@
use crate::utils::{snippet_opt, span_lint_and_then};
use crate::utils::{meets_msrv, snippet_opt, span_lint_and_then};
use if_chain::if_chain;
use rustc_ast::ast::{Attribute, Item, ItemKind, StructField, Variant, VariantData, VisibilityKind};
use rustc_attr as attr;
use rustc_errors::Applicability;
use rustc_lint::{EarlyContext, EarlyLintPass};
use rustc_session::{declare_lint_pass, declare_tool_lint};
use rustc_semver::RustcVersion;
use rustc_session::{declare_tool_lint, impl_lint_pass};
use rustc_span::{sym, Span};
const MANUAL_NON_EXHAUSTIVE_MSRV: RustcVersion = RustcVersion::new(1, 40, 0);
declare_clippy_lint! {
/// **What it does:** Checks for manual implementations of the non-exhaustive pattern.
///
@ -55,10 +58,26 @@ declare_clippy_lint! {
"manual implementations of the non-exhaustive pattern can be simplified using #[non_exhaustive]"
}
declare_lint_pass!(ManualNonExhaustive => [MANUAL_NON_EXHAUSTIVE]);
#[derive(Clone)]
pub struct ManualNonExhaustive {
msrv: Option<RustcVersion>,
}
impl ManualNonExhaustive {
#[must_use]
pub fn new(msrv: Option<RustcVersion>) -> Self {
Self { msrv }
}
}
impl_lint_pass!(ManualNonExhaustive => [MANUAL_NON_EXHAUSTIVE]);
impl EarlyLintPass for ManualNonExhaustive {
fn check_item(&mut self, cx: &EarlyContext<'_>, item: &Item) {
if !meets_msrv(self.msrv.as_ref(), &MANUAL_NON_EXHAUSTIVE_MSRV) {
return;
}
match &item.kind {
ItemKind::Enum(def, _) => {
check_manual_non_exhaustive_enum(cx, item, &def.variants);
@ -73,6 +92,8 @@ impl EarlyLintPass for ManualNonExhaustive {
_ => {},
}
}
extract_msrv_attr!(EarlyContext);
}
fn check_manual_non_exhaustive_enum(cx: &EarlyContext<'_>, item: &Item, variants: &[Variant]) {

31
clippy_lints/src/manual_strip.rs
View file

@ -1,7 +1,7 @@
use crate::consts::{constant, Constant};
use crate::utils::usage::mutated_variables;
use crate::utils::{
eq_expr_value, higher, match_def_path, multispan_sugg, paths, qpath_res, snippet, span_lint_and_then,
eq_expr_value, higher, match_def_path, meets_msrv, multispan_sugg, paths, qpath_res, snippet, span_lint_and_then,
};
use if_chain::if_chain;
@ -10,13 +10,16 @@ use rustc_hir::def::Res;
use rustc_hir::intravisit::{walk_expr, NestedVisitorMap, Visitor};
use rustc_hir::BinOpKind;
use rustc_hir::{BorrowKind, Expr, ExprKind};
use rustc_lint::{LateContext, LateLintPass};
use rustc_lint::{LateContext, LateLintPass, LintContext};
use rustc_middle::hir::map::Map;
use rustc_middle::ty;
use rustc_session::{declare_lint_pass, declare_tool_lint};
use rustc_semver::RustcVersion;
use rustc_session::{declare_tool_lint, impl_lint_pass};
use rustc_span::source_map::Spanned;
use rustc_span::Span;
const MANUAL_STRIP_MSRV: RustcVersion = RustcVersion::new(1, 45, 0);
declare_clippy_lint! {
/// **What it does:**
/// Suggests using `strip_{prefix,suffix}` over `str::{starts,ends}_with` and slicing using
@ -51,7 +54,18 @@ declare_clippy_lint! {
"suggests using `strip_{prefix,suffix}` over `str::{starts,ends}_with` and slicing"
}
declare_lint_pass!(ManualStrip => [MANUAL_STRIP]);
pub struct ManualStrip {
msrv: Option<RustcVersion>,
}
impl ManualStrip {
#[must_use]
pub fn new(msrv: Option<RustcVersion>) -> Self {
Self { msrv }
}
}
impl_lint_pass!(ManualStrip => [MANUAL_STRIP]);
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
enum StripKind {
@ -61,6 +75,10 @@ enum StripKind {
impl<'tcx> LateLintPass<'tcx> for ManualStrip {
fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
if !meets_msrv(self.msrv.as_ref(), &MANUAL_STRIP_MSRV) {
return;
}
if_chain! {
if let Some((cond, then, _)) = higher::if_block(&expr);
if let ExprKind::MethodCall(_, _, [target_arg, pattern], _) = cond.kind;
@ -114,6 +132,8 @@ impl<'tcx> LateLintPass<'tcx> for ManualStrip {
}
}
}
extract_msrv_attr!(LateContext);
}
// Returns `Some(arg)` if `expr` matches `arg.len()` and `None` otherwise.
@ -199,8 +219,7 @@ fn find_stripping<'tcx>(
if is_ref_str(self.cx, ex);
let unref = peel_ref(ex);
if let ExprKind::Index(indexed, index) = &unref.kind;
if let Some(range) = higher::range(index);
if let higher::Range { start, end, .. } = range;
if let Some(higher::Range { start, end, .. }) = higher::range(index);
if let ExprKind::Path(path) = &indexed.kind;
if qpath_res(self.cx, path, ex.hir_id) == self.target;
then {

6
clippy_lints/src/map_err_ignore.rs
View file

@ -99,7 +99,7 @@ declare_clippy_lint! {
/// }
/// ```
pub MAP_ERR_IGNORE,
pedantic,
restriction,
"`map_err` should not ignore the original error"
}
@ -133,9 +133,9 @@ impl<'tcx> LateLintPass<'tcx> for MapErrIgnore {
cx,
MAP_ERR_IGNORE,
body_span,
"`map_err(|_|...` ignores the original error",
"`map_err(|_|...` wildcard pattern discards the original error",
None,
"Consider wrapping the error in an enum variant",
"Consider storing the original error as a source in the new error, or silence this warning using an ignored identifier (`.map_err(|_foo| ...`)",
);
}
}

115
clippy_lints/src/matches.rs
View file

@ -3,8 +3,8 @@ use crate::utils::sugg::Sugg;
use crate::utils::usage::is_unused;
use crate::utils::{
expr_block, get_arg_name, get_parent_expr, in_macro, indent_of, is_allowed, is_expn_of, is_refutable,
is_type_diagnostic_item, is_wild, match_qpath, match_type, match_var, multispan_sugg, remove_blocks, snippet,
snippet_block, snippet_with_applicability, span_lint_and_help, span_lint_and_note, span_lint_and_sugg,
is_type_diagnostic_item, is_wild, match_qpath, match_type, match_var, meets_msrv, multispan_sugg, remove_blocks,
snippet, snippet_block, snippet_with_applicability, span_lint_and_help, span_lint_and_note, span_lint_and_sugg,
span_lint_and_then,
};
use crate::utils::{paths, search_same, SpanlessEq, SpanlessHash};
@ -20,6 +20,7 @@ use rustc_hir::{
use rustc_lint::{LateContext, LateLintPass, LintContext};
use rustc_middle::lint::in_external_macro;
use rustc_middle::ty::{self, Ty, TyS};
use rustc_semver::RustcVersion;
use rustc_session::{declare_tool_lint, impl_lint_pass};
use rustc_span::source_map::{Span, Spanned};
use rustc_span::{sym, Symbol};
@ -411,8 +412,8 @@ declare_clippy_lint! {
}
declare_clippy_lint! {
/// **What it does:** Lint for redundant pattern matching over `Result` or
/// `Option`
/// **What it does:** Lint for redundant pattern matching over `Result`, `Option`,
/// `std::task::Poll` or `std::net::IpAddr`
///
/// **Why is this bad?** It's more concise and clear to just use the proper
/// utility function
@ -422,10 +423,16 @@ declare_clippy_lint! {
/// **Example:**
///
/// ```rust
/// # use std::task::Poll;
/// # use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
/// if let Ok(_) = Ok::<i32, i32>(42) {}
/// if let Err(_) = Err::<i32, i32>(42) {}
/// if let None = None::<()> {}
/// if let Some(_) = Some(42) {}
/// if let Poll::Pending = Poll::Pending::<()> {}
/// if let Poll::Ready(_) = Poll::Ready(42) {}
/// if let IpAddr::V4(_) = IpAddr::V4(Ipv4Addr::LOCALHOST) {}
/// if let IpAddr::V6(_) = IpAddr::V6(Ipv6Addr::LOCALHOST) {}
/// match Ok::<i32, i32>(42) {
/// Ok(_) => true,
/// Err(_) => false,
@ -435,10 +442,16 @@ declare_clippy_lint! {
/// The more idiomatic use would be:
///
/// ```rust
/// # use std::task::Poll;
/// # use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
/// if Ok::<i32, i32>(42).is_ok() {}
/// if Err::<i32, i32>(42).is_err() {}
/// if None::<()>.is_none() {}
/// if Some(42).is_some() {}
/// if Poll::Pending::<()>.is_pending() {}
/// if Poll::Ready(42).is_ready() {}
/// if IpAddr::V4(Ipv4Addr::LOCALHOST).is_ipv4() {}
/// if IpAddr::V6(Ipv6Addr::LOCALHOST).is_ipv6() {}
/// Ok::<i32, i32>(42).is_ok();
/// ```
pub REDUNDANT_PATTERN_MATCHING,
@ -452,7 +465,8 @@ declare_clippy_lint! {
///
/// **Why is this bad?** Readability and needless complexity.
///
/// **Known problems:** None
/// **Known problems:** This lint falsely triggers, if there are arms with
/// `cfg` attributes that remove an arm evaluating to `false`.
///
/// **Example:**
/// ```rust
@ -521,9 +535,20 @@ declare_clippy_lint! {
#[derive(Default)]
pub struct Matches {
msrv: Option<RustcVersion>,
infallible_destructuring_match_linted: bool,
}
impl Matches {
#[must_use]
pub fn new(msrv: Option<RustcVersion>) -> Self {
Self {
msrv,
..Matches::default()
}
}
}
impl_lint_pass!(Matches => [
SINGLE_MATCH,
MATCH_REF_PATS,
@ -543,6 +568,8 @@ impl_lint_pass!(Matches => [
MATCH_SAME_ARMS,
]);
const MATCH_LIKE_MATCHES_MACRO_MSRV: RustcVersion = RustcVersion::new(1, 42, 0);
impl<'tcx> LateLintPass<'tcx> for Matches {
fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
if in_external_macro(cx.sess(), expr.span) || in_macro(expr.span) {
@ -550,7 +577,12 @@ impl<'tcx> LateLintPass<'tcx> for Matches {
}
redundant_pattern_match::check(cx, expr);
if !check_match_like_matches(cx, expr) {
if meets_msrv(self.msrv.as_ref(), &MATCH_LIKE_MATCHES_MACRO_MSRV) {
if !check_match_like_matches(cx, expr) {
lint_match_arms(cx, expr);
}
} else {
lint_match_arms(cx, expr);
}
@ -614,8 +646,7 @@ impl<'tcx> LateLintPass<'tcx> for Matches {
if_chain! {
if !in_external_macro(cx.sess(), pat.span);
if !in_macro(pat.span);
if let PatKind::Struct(ref qpath, fields, true) = pat.kind;
if let QPath::Resolved(_, ref path) = qpath;
if let PatKind::Struct(QPath::Resolved(_, ref path), fields, true) = pat.kind;
if let Some(def_id) = path.res.opt_def_id();
let ty = cx.tcx.type_of(def_id);
if let ty::Adt(def, _) = ty.kind();
@ -634,6 +665,8 @@ impl<'tcx> LateLintPass<'tcx> for Matches {
}
}
}
extract_msrv_attr!(LateContext);
}
#[rustfmt::skip]
@ -922,16 +955,14 @@ fn check_wild_enum_match(cx: &LateContext<'_>, ex: &Expr<'_>, arms: &[Arm<'_>])
if let QPath::Resolved(_, p) = path {
missing_variants.retain(|e| e.ctor_def_id != Some(p.res.def_id()));
}
} else if let PatKind::TupleStruct(ref path, ref patterns, ..) = arm.pat.kind {
if let QPath::Resolved(_, p) = path {
// Some simple checks for exhaustive patterns.
// There is a room for improvements to detect more cases,
// but it can be more expensive to do so.
let is_pattern_exhaustive =
|pat: &&Pat<'_>| matches!(pat.kind, PatKind::Wild | PatKind::Binding(.., None));
if patterns.iter().all(is_pattern_exhaustive) {
missing_variants.retain(|e| e.ctor_def_id != Some(p.res.def_id()));
}
} else if let PatKind::TupleStruct(QPath::Resolved(_, p), ref patterns, ..) = arm.pat.kind {
// Some simple checks for exhaustive patterns.
// There is a room for improvements to detect more cases,
// but it can be more expensive to do so.
let is_pattern_exhaustive =
|pat: &&Pat<'_>| matches!(pat.kind, PatKind::Wild | PatKind::Binding(.., None));
if patterns.iter().all(is_pattern_exhaustive) {
missing_variants.retain(|e| e.ctor_def_id != Some(p.res.def_id()));
}
}
}
@ -1134,13 +1165,16 @@ fn find_matches_sugg(cx: &LateContext<'_>, ex: &Expr<'_>, arms: &[Arm<'_>], expr
if b0 != b1;
let if_guard = &b0_arms[0].guard;
if if_guard.is_none() || b0_arms.len() == 1;
if b0_arms[0].attrs.is_empty();
if b0_arms[1..].iter()
.all(|arm| {
find_bool_lit(&arm.body.kind, desugared).map_or(false, |b| b == b0) &&
arm.guard.is_none()
arm.guard.is_none() && arm.attrs.is_empty()
});
then {
let mut applicability = Applicability::MachineApplicable;
// The suggestion may be incorrect, because some arms can have `cfg` attributes
// evaluated into `false` and so such arms will be stripped before.
let mut applicability = Applicability::MaybeIncorrect;
let pat = {
use itertools::Itertools as _;
b0_arms.iter()
@ -1403,8 +1437,7 @@ fn is_ref_some_arm(arm: &Arm<'_>) -> Option<BindingAnnotation> {
if let ExprKind::Call(ref e, ref args) = remove_blocks(&arm.body).kind;
if let ExprKind::Path(ref some_path) = e.kind;
if match_qpath(some_path, &paths::OPTION_SOME) && args.len() == 1;
if let ExprKind::Path(ref qpath) = args[0].kind;
if let &QPath::Resolved(_, ref path2) = qpath;
if let ExprKind::Path(QPath::Resolved(_, ref path2)) = args[0].kind;
if path2.segments.len() == 1 && ident.name == path2.segments[0].ident.name;
then {
return Some(rb)
@ -1538,6 +1571,12 @@ mod redundant_pattern_match {
"is_err()"
} else if match_qpath(path, &paths::OPTION_SOME) {
"is_some()"
} else if match_qpath(path, &paths::POLL_READY) {
"is_ready()"
} else if match_qpath(path, &paths::IPADDR_V4) {
"is_ipv4()"
} else if match_qpath(path, &paths::IPADDR_V6) {
"is_ipv6()"
} else {
return;
}
@ -1545,7 +1584,15 @@ mod redundant_pattern_match {
return;
}
},
PatKind::Path(ref path) if match_qpath(path, &paths::OPTION_NONE) => "is_none()",
PatKind::Path(ref path) => {
if match_qpath(path, &paths::OPTION_NONE) {
"is_none()"
} else if match_qpath(path, &paths::POLL_PENDING) {
"is_pending()"
} else {
return;
}
},
_ => return,
};
@ -1610,6 +1657,17 @@ mod redundant_pattern_match {
"is_ok()",
"is_err()",
)
.or_else(|| {
find_good_method_for_match(
arms,
path_left,
path_right,
&paths::IPADDR_V4,
&paths::IPADDR_V6,
"is_ipv4()",
"is_ipv6()",
)
})
} else {
None
}
@ -1628,6 +1686,17 @@ mod redundant_pattern_match {
"is_some()",
"is_none()",
)
.or_else(|| {
find_good_method_for_match(
arms,
path_left,
path_right,
&paths::POLL_READY,
&paths::POLL_PENDING,
"is_ready()",
"is_pending()",
)
})
} else {
None
}

3
clippy_lints/src/methods/manual_saturating_arithmetic.rs
View file

@ -90,8 +90,7 @@ fn is_min_or_max<'tcx>(cx: &LateContext<'tcx>, expr: &hir::Expr<'_>) -> Option<M
if_chain! {
if let hir::ExprKind::Call(func, args) = &expr.kind;
if args.is_empty();
if let hir::ExprKind::Path(path) = &func.kind;
if let hir::QPath::TypeRelative(_, segment) = path;
if let hir::ExprKind::Path(hir::QPath::TypeRelative(_, segment)) = &func.kind;
then {
match &*segment.ident.as_str() {
"max_value" => return Some(MinMax::Max),

76
clippy_lints/src/methods/mod.rs
View file

@ -14,13 +14,12 @@ use if_chain::if_chain;
use rustc_ast::ast;
use rustc_errors::Applicability;
use rustc_hir as hir;
use rustc_hir::intravisit::{self, Visitor};
use rustc_hir::{TraitItem, TraitItemKind};
use rustc_lint::{LateContext, LateLintPass, Lint, LintContext};
use rustc_middle::hir::map::Map;
use rustc_middle::lint::in_external_macro;
use rustc_middle::ty::{self, TraitRef, Ty, TyS};
use rustc_session::{declare_lint_pass, declare_tool_lint};
use rustc_semver::RustcVersion;
use rustc_session::{declare_tool_lint, impl_lint_pass};
use rustc_span::source_map::Span;
use rustc_span::symbol::{sym, SymbolStr};
@ -28,11 +27,12 @@ use crate::consts::{constant, Constant};
use crate::utils::eager_or_lazy::is_lazyness_candidate;
use crate::utils::usage::mutated_variables;
use crate::utils::{
contains_ty, get_arg_name, get_parent_expr, get_trait_def_id, has_iter_method, higher, implements_trait, in_macro,
is_copy, is_expn_of, is_type_diagnostic_item, iter_input_pats, last_path_segment, match_def_path, match_qpath,
match_trait_method, match_type, match_var, method_calls, method_chain_args, paths, remove_blocks, return_ty,
single_segment_path, snippet, snippet_with_applicability, snippet_with_macro_callsite, span_lint,
span_lint_and_help, span_lint_and_sugg, span_lint_and_then, sugg, walk_ptrs_ty_depth, SpanlessEq,
contains_return, contains_ty, get_arg_name, get_parent_expr, get_trait_def_id, has_iter_method, higher,
implements_trait, in_macro, is_copy, is_expn_of, is_type_diagnostic_item, iter_input_pats, last_path_segment,
match_def_path, match_qpath, match_trait_method, match_type, match_var, meets_msrv, method_calls,
method_chain_args, paths, remove_blocks, return_ty, single_segment_path, snippet, snippet_with_applicability,
snippet_with_macro_callsite, span_lint, span_lint_and_help, span_lint_and_sugg, span_lint_and_then, sugg,
walk_ptrs_ty_depth, SpanlessEq,
};
declare_clippy_lint! {
@ -1404,7 +1404,18 @@ declare_clippy_lint! {
"use `.collect()` instead of `::from_iter()`"
}
declare_lint_pass!(Methods => [
pub struct Methods {
msrv: Option<RustcVersion>,
}
impl Methods {
#[must_use]
pub fn new(msrv: Option<RustcVersion>) -> Self {
Self { msrv }
}
}
impl_lint_pass!(Methods => [
UNWRAP_USED,
EXPECT_USED,
SHOULD_IMPLEMENT_TRAIT,
@ -1531,8 +1542,12 @@ impl<'tcx> LateLintPass<'tcx> for Methods {
check_pointer_offset(cx, expr, arg_lists[0])
},
["is_file", ..] => lint_filetype_is_file(cx, expr, arg_lists[0]),
["map", "as_ref"] => lint_option_as_ref_deref(cx, expr, arg_lists[1], arg_lists[0], false),
["map", "as_mut"] => lint_option_as_ref_deref(cx, expr, arg_lists[1], arg_lists[0], true),
["map", "as_ref"] => {
lint_option_as_ref_deref(cx, expr, arg_lists[1], arg_lists[0], false, self.msrv.as_ref())
},
["map", "as_mut"] => {
lint_option_as_ref_deref(cx, expr, arg_lists[1], arg_lists[0], true, self.msrv.as_ref())
},
["unwrap_or_else", ..] => unnecessary_lazy_eval::lint(cx, expr, arg_lists[0], "unwrap_or"),
["get_or_insert_with", ..] => unnecessary_lazy_eval::lint(cx, expr, arg_lists[0], "get_or_insert"),
["ok_or_else", ..] => unnecessary_lazy_eval::lint(cx, expr, arg_lists[0], "ok_or"),
@ -1738,6 +1753,8 @@ impl<'tcx> LateLintPass<'tcx> for Methods {
}
}
}
extract_msrv_attr!(LateContext);
}
/// Checks for the `OR_FUN_CALL` lint.
@ -3453,6 +3470,8 @@ fn lint_suspicious_map(cx: &LateContext<'_>, expr: &hir::Expr<'_>) {
);
}
const OPTION_AS_REF_DEREF_MSRV: RustcVersion = RustcVersion::new(1, 40, 0);
/// lint use of `_.as_ref().map(Deref::deref)` for `Option`s
fn lint_option_as_ref_deref<'tcx>(
cx: &LateContext<'tcx>,
@ -3460,7 +3479,12 @@ fn lint_option_as_ref_deref<'tcx>(
as_ref_args: &[hir::Expr<'_>],
map_args: &[hir::Expr<'_>],
is_mut: bool,
msrv: Option<&RustcVersion>,
) {
if !meets_msrv(msrv, &OPTION_AS_REF_DEREF_MSRV) {
return;
}
let same_mutability = |m| (is_mut && m == &hir::Mutability::Mut) || (!is_mut && m == &hir::Mutability::Not);
let option_ty = cx.typeck_results().expr_ty(&as_ref_args[0]);
@ -3846,36 +3870,6 @@ fn is_bool(ty: &hir::Ty<'_>) -> bool {
}
}
// Returns `true` if `expr` contains a return expression
fn contains_return(expr: &hir::Expr<'_>) -> bool {
struct RetCallFinder {
found: bool,
}
impl<'tcx> intravisit::Visitor<'tcx> for RetCallFinder {
type Map = Map<'tcx>;
fn visit_expr(&mut self, expr: &'tcx hir::Expr<'_>) {
if self.found {
return;
}
if let hir::ExprKind::Ret(..) = &expr.kind {
self.found = true;
} else {
intravisit::walk_expr(self, expr);
}
}
fn nested_visit_map(&mut self) -> intravisit::NestedVisitorMap<Self::Map> {
intravisit::NestedVisitorMap::None
}
}
let mut visitor = RetCallFinder { found: false };
visitor.visit_expr(expr);
visitor.found
}
fn check_pointer_offset(cx: &LateContext<'_>, expr: &hir::Expr<'_>, args: &[hir::Expr<'_>]) {
if_chain! {
if args.len() == 2;

144
clippy_lints/src/misc.rs
View file

@ -18,7 +18,7 @@ use crate::utils::sugg::Sugg;
use crate::utils::{
get_item_name, get_parent_expr, higher, implements_trait, in_constant, is_integer_const, iter_input_pats,
last_path_segment, match_qpath, match_trait_method, paths, snippet, snippet_opt, span_lint, span_lint_and_sugg,
span_lint_and_then, span_lint_hir_and_then, SpanlessEq,
span_lint_and_then, span_lint_hir_and_then, unsext, SpanlessEq,
};
declare_clippy_lint! {
@ -139,12 +139,14 @@ declare_clippy_lint! {
}
declare_clippy_lint! {
/// **What it does:** Checks for getting the remainder of a division by one.
/// **What it does:** Checks for getting the remainder of a division by one or minus
/// one.
///
/// **Why is this bad?** The result can only ever be zero. No one will write
/// such code deliberately, unless trying to win an Underhanded Rust
/// Contest. Even for that contest, it's probably a bad idea. Use something more
/// underhanded.
/// **Why is this bad?** The result for a divisor of one can only ever be zero; for
/// minus one it can cause panic/overflow (if the left operand is the minimal value of
/// the respective integer type) or results in zero. No one will write such code
/// deliberately, unless trying to win an Underhanded Rust Contest. Even for that
/// contest, it's probably a bad idea. Use something more underhanded.
///
/// **Known problems:** None.
///
@ -152,10 +154,11 @@ declare_clippy_lint! {
/// ```rust
/// # let x = 1;
/// let a = x % 1;
/// let a = x % -1;
/// ```
pub MODULO_ONE,
correctness,
"taking a number modulo 1, which always returns 0"
"taking a number modulo +/-1, which can either panic/overflow or always returns 0"
}
declare_clippy_lint! {
@ -378,60 +381,8 @@ impl<'tcx> LateLintPass<'tcx> for MiscLints {
return;
},
ExprKind::Binary(ref cmp, ref left, ref right) => {
let op = cmp.node;
if op.is_comparison() {
check_nan(cx, left, expr);
check_nan(cx, right, expr);
check_to_owned(cx, left, right, true);
check_to_owned(cx, right, left, false);
}
if (op == BinOpKind::Eq || op == BinOpKind::Ne) && (is_float(cx, left) || is_float(cx, right)) {
if is_allowed(cx, left) || is_allowed(cx, right) {
return;
}
// Allow comparing the results of signum()
if is_signum(cx, left) && is_signum(cx, right) {
return;
}
if let Some(name) = get_item_name(cx, expr) {
let name = name.as_str();
if name == "eq"
|| name == "ne"
|| name == "is_nan"
|| name.starts_with("eq_")
|| name.ends_with("_eq")
{
return;
}
}
let is_comparing_arrays = is_array(cx, left) || is_array(cx, right);
let (lint, msg) = get_lint_and_message(
is_named_constant(cx, left) || is_named_constant(cx, right),
is_comparing_arrays,
);
span_lint_and_then(cx, lint, expr.span, msg, |diag| {
let lhs = Sugg::hir(cx, left, "..");
let rhs = Sugg::hir(cx, right, "..");
if !is_comparing_arrays {
diag.span_suggestion(
expr.span,
"consider comparing them within some margin of error",
format!(
"({}).abs() {} error_margin",
lhs - rhs,
if op == BinOpKind::Eq { '<' } else { '>' }
),
Applicability::HasPlaceholders, // snippet
);
}
diag.note("`f32::EPSILON` and `f64::EPSILON` are available for the `error_margin`");
});
} else if op == BinOpKind::Rem && is_integer_const(cx, right, 1) {
span_lint(cx, MODULO_ONE, expr.span, "any number modulo 1 will be 0");
}
check_binary(cx, expr, cmp, left, right);
return;
},
_ => {},
}
@ -744,3 +695,74 @@ fn check_cast(cx: &LateContext<'_>, span: Span, e: &Expr<'_>, ty: &hir::Ty<'_>)
}
}
}
fn check_binary(
cx: &LateContext<'a>,
expr: &Expr<'_>,
cmp: &rustc_span::source_map::Spanned<rustc_hir::BinOpKind>,
left: &'a Expr<'_>,
right: &'a Expr<'_>,
) {
let op = cmp.node;
if op.is_comparison() {
check_nan(cx, left, expr);
check_nan(cx, right, expr);
check_to_owned(cx, left, right, true);
check_to_owned(cx, right, left, false);
}
if (op == BinOpKind::Eq || op == BinOpKind::Ne) && (is_float(cx, left) || is_float(cx, right)) {
if is_allowed(cx, left) || is_allowed(cx, right) {
return;
}
// Allow comparing the results of signum()
if is_signum(cx, left) && is_signum(cx, right) {
return;
}
if let Some(name) = get_item_name(cx, expr) {
let name = name.as_str();
if name == "eq" || name == "ne" || name == "is_nan" || name.starts_with("eq_") || name.ends_with("_eq") {
return;
}
}
let is_comparing_arrays = is_array(cx, left) || is_array(cx, right);
let (lint, msg) = get_lint_and_message(
is_named_constant(cx, left) || is_named_constant(cx, right),
is_comparing_arrays,
);
span_lint_and_then(cx, lint, expr.span, msg, |diag| {
let lhs = Sugg::hir(cx, left, "..");
let rhs = Sugg::hir(cx, right, "..");
if !is_comparing_arrays {
diag.span_suggestion(
expr.span,
"consider comparing them within some margin of error",
format!(
"({}).abs() {} error_margin",
lhs - rhs,
if op == BinOpKind::Eq { '<' } else { '>' }
),
Applicability::HasPlaceholders, // snippet
);
}
diag.note("`f32::EPSILON` and `f64::EPSILON` are available for the `error_margin`");
});
} else if op == BinOpKind::Rem {
if is_integer_const(cx, right, 1) {
span_lint(cx, MODULO_ONE, expr.span, "any number modulo 1 will be 0");
}
if let ty::Int(ity) = cx.typeck_results().expr_ty(right).kind() {
if is_integer_const(cx, right, unsext(cx.tcx, -1, *ity)) {
span_lint(
cx,
MODULO_ONE,
expr.span,
"any number modulo -1 will panic/overflow or result in 0",
);
}
};
}
}

11
clippy_lints/src/needless_bool.rs
View file

@ -6,7 +6,6 @@ use crate::utils::sugg::Sugg;
use crate::utils::{
higher, is_expn_of, parent_node_is_if_expr, snippet_with_applicability, span_lint, span_lint_and_sugg,
};
use if_chain::if_chain;
use rustc_ast::ast::LitKind;
use rustc_errors::Applicability;
use rustc_hir::{BinOpKind, Block, Expr, ExprKind, StmtKind, UnOp};
@ -198,13 +197,9 @@ struct ExpressionInfoWithSpan {
}
fn is_unary_not(e: &Expr<'_>) -> (bool, Span) {
if_chain! {
if let ExprKind::Unary(unop, operand) = e.kind;
if let UnOp::UnNot = unop;
then {
return (true, operand.span);
}
};
if let ExprKind::Unary(UnOp::UnNot, operand) = e.kind {
return (true, operand.span);
}
(false, e.span)
}

9
clippy_lints/src/panic_unimplemented.rs
View file

@ -66,7 +66,7 @@ declare_clippy_lint! {
/// ```
pub UNREACHABLE,
restriction,
"`unreachable!` should not be present in production code"
"usage of the `unreachable!` macro"
}
declare_lint_pass!(PanicUnimplemented => [UNIMPLEMENTED, UNREACHABLE, TODO, PANIC]);
@ -85,12 +85,7 @@ impl<'tcx> LateLintPass<'tcx> for PanicUnimplemented {
} else if is_expn_of(expr.span, "todo").is_some() {
span_lint(cx, TODO, span, "`todo` should not be present in production code");
} else if is_expn_of(expr.span, "unreachable").is_some() {
span_lint(
cx,
UNREACHABLE,
span,
"`unreachable` should not be present in production code",
);
span_lint(cx, UNREACHABLE, span, "usage of the `unreachable!` macro");
} else if is_expn_of(expr.span, "panic").is_some() {
span_lint(cx, PANIC, span, "`panic` should not be present in production code");
}

3
clippy_lints/src/question_mark.rs
View file

@ -176,8 +176,7 @@ impl QuestionMark {
if block.stmts.len() == 1;
if let Some(expr) = block.stmts.iter().last();
if let StmtKind::Semi(ref expr) = expr.kind;
if let ExprKind::Ret(ret_expr) = expr.kind;
if let Some(ret_expr) = ret_expr;
if let ExprKind::Ret(Some(ret_expr)) = expr.kind;
then {
return Some(ret_expr);

4
clippy_lints/src/redundant_closure_call.rs
View file

@ -104,7 +104,7 @@ impl<'tcx> LateLintPass<'tcx> for RedundantClosureCall {
cx: &'a LateContext<'tcx>,
path: &'tcx hir::Path<'tcx>,
count: usize,
};
}
impl<'a, 'tcx> hir_visit::Visitor<'tcx> for ClosureUsageCount<'a, 'tcx> {
type Map = Map<'tcx>;
@ -124,7 +124,7 @@ impl<'tcx> LateLintPass<'tcx> for RedundantClosureCall {
fn nested_visit_map(&mut self) -> hir_visit::NestedVisitorMap<Self::Map> {
hir_visit::NestedVisitorMap::OnlyBodies(self.cx.tcx.hir())
}
};
}
let mut closure_usage_count = ClosureUsageCount { cx, path, count: 0 };
closure_usage_count.visit_block(block);
closure_usage_count.count

145
clippy_lints/src/size_of_in_element_count.rs Normal file
View file

@ -0,0 +1,145 @@
//! Lint on use of `size_of` or `size_of_val` of T in an expression
//! expecting a count of T
use crate::utils::{match_def_path, paths, span_lint_and_help};
use if_chain::if_chain;
use rustc_hir::BinOpKind;
use rustc_hir::{Expr, ExprKind};
use rustc_lint::{LateContext, LateLintPass};
use rustc_middle::ty::{self, Ty, TyS, TypeAndMut};
use rustc_session::{declare_lint_pass, declare_tool_lint};
declare_clippy_lint! {
/// **What it does:** Detects expressions where
/// `size_of::<T>` or `size_of_val::<T>` is used as a
/// count of elements of type `T`
///
/// **Why is this bad?** These functions expect a count
/// of `T` and not a number of bytes
///
/// **Known problems:** None.
///
/// **Example:**
/// ```rust,no_run
/// # use std::ptr::copy_nonoverlapping;
/// # use std::mem::size_of;
/// const SIZE: usize = 128;
/// let x = [2u8; SIZE];
/// let mut y = [2u8; SIZE];
/// unsafe { copy_nonoverlapping(x.as_ptr(), y.as_mut_ptr(), size_of::<u8>() * SIZE) };
/// ```
pub SIZE_OF_IN_ELEMENT_COUNT,
correctness,
"using `size_of::<T>` or `size_of_val::<T>` where a count of elements of `T` is expected"
}
declare_lint_pass!(SizeOfInElementCount => [SIZE_OF_IN_ELEMENT_COUNT]);
fn get_size_of_ty(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) -> Option<Ty<'tcx>> {
match expr.kind {
ExprKind::Call(count_func, _func_args) => {
if_chain! {
if let ExprKind::Path(ref count_func_qpath) = count_func.kind;
if let Some(def_id) = cx.qpath_res(count_func_qpath, count_func.hir_id).opt_def_id();
if match_def_path(cx, def_id, &paths::MEM_SIZE_OF)
|| match_def_path(cx, def_id, &paths::MEM_SIZE_OF_VAL);
then {
cx.typeck_results().node_substs(count_func.hir_id).types().next()
} else {
None
}
}
},
ExprKind::Binary(op, left, right) if BinOpKind::Mul == op.node || BinOpKind::Div == op.node => {
get_size_of_ty(cx, left).or_else(|| get_size_of_ty(cx, right))
},
ExprKind::Cast(expr, _) => get_size_of_ty(cx, expr),
_ => None,
}
}
fn get_pointee_ty_and_count_expr(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) -> Option<(Ty<'tcx>, &'tcx Expr<'tcx>)> {
const FUNCTIONS: [&[&str]; 8] = [
&paths::COPY_NONOVERLAPPING,
&paths::COPY,
&paths::WRITE_BYTES,
&paths::PTR_SWAP_NONOVERLAPPING,
&paths::PTR_SLICE_FROM_RAW_PARTS,
&paths::PTR_SLICE_FROM_RAW_PARTS_MUT,
&paths::SLICE_FROM_RAW_PARTS,
&paths::SLICE_FROM_RAW_PARTS_MUT,
];
const METHODS: [&str; 11] = [
"write_bytes",
"copy_to",
"copy_from",
"copy_to_nonoverlapping",
"copy_from_nonoverlapping",
"add",
"wrapping_add",
"sub",
"wrapping_sub",
"offset",
"wrapping_offset",
];
if_chain! {
// Find calls to ptr::{copy, copy_nonoverlapping}
// and ptr::{swap_nonoverlapping, write_bytes},
if let ExprKind::Call(func, [.., count]) = expr.kind;
if let ExprKind::Path(ref func_qpath) = func.kind;
if let Some(def_id) = cx.qpath_res(func_qpath, func.hir_id).opt_def_id();
if FUNCTIONS.iter().any(|func_path| match_def_path(cx, def_id, func_path));
// Get the pointee type
if let Some(pointee_ty) = cx.typeck_results().node_substs(func.hir_id).types().next();
then {
return Some((pointee_ty, count));
}
};
if_chain! {
// Find calls to copy_{from,to}{,_nonoverlapping} and write_bytes methods
if let ExprKind::MethodCall(method_path, _, [ptr_self, .., count], _) = expr.kind;
let method_ident = method_path.ident.as_str();
if METHODS.iter().any(|m| *m == &*method_ident);
// Get the pointee type
if let ty::RawPtr(TypeAndMut { ty: pointee_ty, .. }) =
cx.typeck_results().expr_ty(ptr_self).kind();
then {
return Some((pointee_ty, count));
}
};
None
}
impl<'tcx> LateLintPass<'tcx> for SizeOfInElementCount {
fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
const HELP_MSG: &str = "use a count of elements instead of a count of bytes\
, it already gets multiplied by the size of the type";
const LINT_MSG: &str = "found a count of bytes \
instead of a count of elements of `T`";
if_chain! {
// Find calls to functions with an element count parameter and get
// the pointee type and count parameter expression
if let Some((pointee_ty, count_expr)) = get_pointee_ty_and_count_expr(cx, expr);
// Find a size_of call in the count parameter expression and
// check that it's the same type
if let Some(ty_used_for_size_of) = get_size_of_ty(cx, count_expr);
if TyS::same_type(pointee_ty, ty_used_for_size_of);
then {
span_lint_and_help(
cx,
SIZE_OF_IN_ELEMENT_COUNT,
count_expr.span,
LINT_MSG,
None,
HELP_MSG
);
}
};
}
}

103
clippy_lints/src/strings.rs
View file

@ -2,6 +2,7 @@ use rustc_errors::Applicability;
use rustc_hir::{BinOpKind, BorrowKind, Expr, ExprKind, LangItem, QPath};
use rustc_lint::{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_span::source_map::Spanned;
use rustc_span::sym;
@ -11,7 +12,7 @@ use if_chain::if_chain;
use crate::utils::SpanlessEq;
use crate::utils::{
get_parent_expr, is_allowed, is_type_diagnostic_item, match_function_call, method_calls, paths, span_lint,
span_lint_and_sugg,
span_lint_and_help, span_lint_and_sugg,
};
declare_clippy_lint! {
@ -221,8 +222,7 @@ impl<'tcx> LateLintPass<'tcx> for StringLitAsBytes {
if method_names[0] == sym!(as_bytes);
// Check for slicer
if let ExprKind::Struct(ref path, _, _) = right.kind;
if let QPath::LangItem(LangItem::Range, _) = path;
if let ExprKind::Struct(QPath::LangItem(LangItem::Range, _), _, _) = right.kind;
then {
let mut applicability = Applicability::MachineApplicable;
@ -289,3 +289,100 @@ impl<'tcx> LateLintPass<'tcx> for StringLitAsBytes {
}
}
}
declare_clippy_lint! {
/// **What it does:** This lint checks for `.to_string()` method calls on values of type `&str`.
///
/// **Why is this bad?** The `to_string` method is also used on other types to convert them to a string.
/// When called on a `&str` it turns the `&str` into the owned variant `String`, which can be better
/// expressed with `.to_owned()`.
///
/// **Known problems:** None.
///
/// **Example:**
///
/// ```rust
/// // example code where clippy issues a warning
/// let _ = "str".to_string();
/// ```
/// Use instead:
/// ```rust
/// // example code which does not raise clippy warning
/// let _ = "str".to_owned();
/// ```
pub STR_TO_STRING,
restriction,
"using `to_string()` on a `&str`, which should be `to_owned()`"
}
declare_lint_pass!(StrToString => [STR_TO_STRING]);
impl LateLintPass<'_> for StrToString {
fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &Expr<'_>) {
if_chain! {
if let ExprKind::MethodCall(path, _, args, _) = &expr.kind;
if path.ident.name == sym!(to_string);
let ty = cx.typeck_results().expr_ty(&args[0]);
if let ty::Ref(_, ty, ..) = ty.kind();
if *ty.kind() == ty::Str;
then {
span_lint_and_help(
cx,
STR_TO_STRING,
expr.span,
"`to_string()` called on a `&str`",
None,
"consider using `.to_owned()`",
);
}
}
}
}
declare_clippy_lint! {
/// **What it does:** This lint checks for `.to_string()` method calls on values of type `String`.
///
/// **Why is this bad?** The `to_string` method is also used on other types to convert them to a string.
/// When called on a `String` it only clones the `String`, which can be better expressed with `.clone()`.
/// **Known problems:** None.
///
/// **Example:**
///
/// ```rust
/// // example code where clippy issues a warning
/// let msg = String::from("Hello World");
/// let _ = msg.to_string();
/// ```
/// Use instead:
/// ```rust
/// // example code which does not raise clippy warning
/// let msg = String::from("Hello World");
/// let _ = msg.clone();
/// ```
pub STRING_TO_STRING,
restriction,
"using `to_string()` on a `String`, which should be `clone()`"
}
declare_lint_pass!(StringToString => [STRING_TO_STRING]);
impl LateLintPass<'_> for StringToString {
fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &Expr<'_>) {
if_chain! {
if let ExprKind::MethodCall(path, _, args, _) = &expr.kind;
if path.ident.name == sym!(to_string);
let ty = cx.typeck_results().expr_ty(&args[0]);
if is_type_diagnostic_item(cx, ty, sym!(string_type));
then {
span_lint_and_help(
cx,
STRING_TO_STRING,
expr.span,
"`to_string()` called on a `String`",
None,
"consider using `.clone()`",
);
}
}
}
}

693
clippy_lints/src/suspicious_operation_groupings.rs Normal file
View file

@ -0,0 +1,693 @@
use crate::utils::ast_utils::{eq_id, is_useless_with_eq_exprs, IdentIter};
use crate::utils::{snippet_with_applicability, span_lint_and_sugg};
use core::ops::{Add, AddAssign};
use if_chain::if_chain;
use rustc_ast::ast::{BinOpKind, Expr, ExprKind, StmtKind};
use rustc_data_structures::fx::FxHashSet;
use rustc_errors::Applicability;
use rustc_lint::{EarlyContext, EarlyLintPass};
use rustc_session::{declare_lint_pass, declare_tool_lint};
use rustc_span::source_map::Spanned;
use rustc_span::symbol::Ident;
use rustc_span::Span;
declare_clippy_lint! {
/// **What it does:**
/// Checks for unlikely usages of binary operators that are almost
/// certainly typos and/or copy/paste errors, given the other usages
/// of binary operators nearby.
/// **Why is this bad?**
/// They are probably bugs and if they aren't then they look like bugs
/// and you should add a comment explaining why you are doing such an
/// odd set of operations.
/// **Known problems:**
/// There may be some false positives if you are trying to do something
/// unusual that happens to look like a typo.
///
/// **Example:**
///
/// ```rust
/// struct Vec3 {
/// x: f64,
/// y: f64,
/// z: f64,
/// }
///
/// impl Eq for Vec3 {}
///
/// impl PartialEq for Vec3 {
/// fn eq(&self, other: &Self) -> bool {
/// // This should trigger the lint because `self.x` is compared to `other.y`
/// self.x == other.y && self.y == other.y && self.z == other.z
/// }
/// }
/// ```
/// Use instead:
/// ```rust
/// # struct Vec3 {
/// # x: f64,
/// # y: f64,
/// # z: f64,
/// # }
/// // same as above except:
/// impl PartialEq for Vec3 {
/// fn eq(&self, other: &Self) -> bool {
/// // Note we now compare other.x to self.x
/// self.x == other.x && self.y == other.y && self.z == other.z
/// }
/// }
/// ```
pub SUSPICIOUS_OPERATION_GROUPINGS,
style,
"groupings of binary operations that look suspiciously like typos"
}
declare_lint_pass!(SuspiciousOperationGroupings => [SUSPICIOUS_OPERATION_GROUPINGS]);
impl EarlyLintPass for SuspiciousOperationGroupings {
fn check_expr(&mut self, cx: &EarlyContext<'_>, expr: &Expr) {
if expr.span.from_expansion() {
return;
}
if let Some(binops) = extract_related_binops(&expr.kind) {
check_binops(cx, &binops.iter().collect::<Vec<_>>());
let mut op_types = Vec::with_capacity(binops.len());
// We could use a hashmap, etc. to avoid being O(n*m) here, but
// we want the lints to be emitted in a consistent order. Besides,
// m, (the number of distinct `BinOpKind`s in `binops`)
// will often be small, and does have an upper limit.
binops.iter().map(|b| b.op).for_each(|op| {
if !op_types.contains(&op) {
op_types.push(op);
}
});
for op_type in op_types {
let ops: Vec<_> = binops.iter().filter(|b| b.op == op_type).collect();
check_binops(cx, &ops);
}
}
}
}
fn check_binops(cx: &EarlyContext<'_>, binops: &[&BinaryOp<'_>]) {
let binop_count = binops.len();
if binop_count < 2 {
// Single binary operation expressions would likely be false
// positives.
return;
}
let mut one_ident_difference_count = 0;
let mut no_difference_info = None;
let mut double_difference_info = None;
let mut expected_ident_loc = None;
let mut paired_identifiers = FxHashSet::default();
for (i, BinaryOp { left, right, op, .. }) in binops.iter().enumerate() {
match ident_difference_expr(left, right) {
IdentDifference::NoDifference => {
if is_useless_with_eq_exprs(*op) {
// The `eq_op` lint should catch this in this case.
return;
}
no_difference_info = Some(i);
},
IdentDifference::Single(ident_loc) => {
one_ident_difference_count += 1;
if let Some(previous_expected) = expected_ident_loc {
if previous_expected != ident_loc {
// This expression doesn't match the form we're
// looking for.
return;
}
} else {
expected_ident_loc = Some(ident_loc);
}
// If there was only a single difference, all other idents
// must have been the same, and thus were paired.
for id in skip_index(IdentIter::from(*left), ident_loc.index) {
paired_identifiers.insert(id);
}
},
IdentDifference::Double(ident_loc1, ident_loc2) => {
double_difference_info = Some((i, ident_loc1, ident_loc2));
},
IdentDifference::Multiple | IdentDifference::NonIdent => {
// It's too hard to know whether this is a bug or not.
return;
},
}
}
let mut applicability = Applicability::MachineApplicable;
if let Some(expected_loc) = expected_ident_loc {
match (no_difference_info, double_difference_info) {
(Some(i), None) => attempt_to_emit_no_difference_lint(cx, binops, i, expected_loc),
(None, Some((double_difference_index, ident_loc1, ident_loc2))) => {
if_chain! {
if one_ident_difference_count == binop_count - 1;
if let Some(binop) = binops.get(double_difference_index);
then {
let changed_loc = if ident_loc1 == expected_loc {
ident_loc2
} else if ident_loc2 == expected_loc {
ident_loc1
} else {
// This expression doesn't match the form we're
// looking for.
return;
};
if let Some(sugg) = ident_swap_sugg(
cx,
&paired_identifiers,
binop,
changed_loc,
&mut applicability,
) {
emit_suggestion(
cx,
binop.span,
sugg,
applicability,
);
}
}
}
},
_ => {},
}
}
}
fn attempt_to_emit_no_difference_lint(
cx: &EarlyContext<'_>,
binops: &[&BinaryOp<'_>],
i: usize,
expected_loc: IdentLocation,
) {
if let Some(binop) = binops.get(i).cloned() {
// We need to try and figure out which identifier we should
// suggest using instead. Since there could be multiple
// replacement candidates in a given expression, and we're
// just taking the first one, we may get some bad lint
// messages.
let mut applicability = Applicability::MaybeIncorrect;
// We assume that the correct ident is one used elsewhere in
// the other binops, in a place that there was a single
// difference between idents before.
let old_left_ident = get_ident(binop.left, expected_loc);
let old_right_ident = get_ident(binop.right, expected_loc);
for b in skip_index(binops.iter(), i) {
if_chain! {
if let (Some(old_ident), Some(new_ident)) =
(old_left_ident, get_ident(b.left, expected_loc));
if old_ident != new_ident;
if let Some(sugg) = suggestion_with_swapped_ident(
cx,
binop.left,
expected_loc,
new_ident,
&mut applicability,
);
then {
emit_suggestion(
cx,
binop.span,
replace_left_sugg(cx, &binop, &sugg, &mut applicability),
applicability,
);
return;
}
}
if_chain! {
if let (Some(old_ident), Some(new_ident)) =
(old_right_ident, get_ident(b.right, expected_loc));
if old_ident != new_ident;
if let Some(sugg) = suggestion_with_swapped_ident(
cx,
binop.right,
expected_loc,
new_ident,
&mut applicability,
);
then {
emit_suggestion(
cx,
binop.span,
replace_right_sugg(cx, &binop, &sugg, &mut applicability),
applicability,
);
return;
}
}
}
}
}
fn emit_suggestion(cx: &EarlyContext<'_>, span: Span, sugg: String, applicability: Applicability) {
span_lint_and_sugg(
cx,
SUSPICIOUS_OPERATION_GROUPINGS,
span,
"This sequence of operators looks suspiciously like a bug.",
"I think you meant",
sugg,
applicability,
)
}
fn ident_swap_sugg(
cx: &EarlyContext<'_>,
paired_identifiers: &FxHashSet<Ident>,
binop: &BinaryOp<'_>,
location: IdentLocation,
applicability: &mut Applicability,
) -> Option<String> {
let left_ident = get_ident(&binop.left, location)?;
let right_ident = get_ident(&binop.right, location)?;
let sugg = match (
paired_identifiers.contains(&left_ident),
paired_identifiers.contains(&right_ident),
) {
(true, true) | (false, false) => {
// We don't have a good guess of what ident should be
// used instead, in these cases.
*applicability = Applicability::MaybeIncorrect;
// We arbitraily choose one side to suggest changing,
// since we don't have a better guess. If the user
// ends up duplicating a clause, the `logic_bug` lint
// should catch it.
let right_suggestion =
suggestion_with_swapped_ident(cx, &binop.right, location, left_ident, applicability)?;
replace_right_sugg(cx, binop, &right_suggestion, applicability)
},
(false, true) => {
// We haven't seen a pair involving the left one, so
// it's probably what is wanted.
let right_suggestion =
suggestion_with_swapped_ident(cx, &binop.right, location, left_ident, applicability)?;
replace_right_sugg(cx, binop, &right_suggestion, applicability)
},
(true, false) => {
// We haven't seen a pair involving the right one, so
// it's probably what is wanted.
let left_suggestion = suggestion_with_swapped_ident(cx, &binop.left, location, right_ident, applicability)?;
replace_left_sugg(cx, binop, &left_suggestion, applicability)
},
};
Some(sugg)
}
fn replace_left_sugg(
cx: &EarlyContext<'_>,
binop: &BinaryOp<'_>,
left_suggestion: &str,
applicability: &mut Applicability,
) -> String {
format!(
"{} {} {}",
left_suggestion,
binop.op.to_string(),
snippet_with_applicability(cx, binop.right.span, "..", applicability),
)
}
fn replace_right_sugg(
cx: &EarlyContext<'_>,
binop: &BinaryOp<'_>,
right_suggestion: &str,
applicability: &mut Applicability,
) -> String {
format!(
"{} {} {}",
snippet_with_applicability(cx, binop.left.span, "..", applicability),
binop.op.to_string(),
right_suggestion,
)
}
#[derive(Clone, Debug)]
struct BinaryOp<'exprs> {
op: BinOpKind,
span: Span,
left: &'exprs Expr,
right: &'exprs Expr,
}
impl BinaryOp<'exprs> {
fn new(op: BinOpKind, span: Span, (left, right): (&'exprs Expr, &'exprs Expr)) -> Self {
Self { op, span, left, right }
}
}
fn strip_non_ident_wrappers(expr: &Expr) -> &Expr {
let mut output = expr;
loop {
output = match &output.kind {
ExprKind::Paren(ref inner) | ExprKind::Unary(_, ref inner) => inner,
_ => {
return output;
},
};
}
}
fn extract_related_binops(kind: &ExprKind) -> Option<Vec<BinaryOp<'_>>> {
append_opt_vecs(chained_binops(kind), if_statment_binops(kind))
}
fn if_statment_binops(kind: &ExprKind) -> Option<Vec<BinaryOp<'_>>> {
match kind {
ExprKind::If(ref condition, _, _) => chained_binops(&condition.kind),
ExprKind::Paren(ref e) => if_statment_binops(&e.kind),
ExprKind::Block(ref block, _) => {
let mut output = None;
for stmt in &block.stmts {
match stmt.kind {
StmtKind::Expr(ref e) | StmtKind::Semi(ref e) => {
output = append_opt_vecs(output, if_statment_binops(&e.kind));
},
_ => {},
}
}
output
},
_ => None,
}
}
fn append_opt_vecs<A>(target_opt: Option<Vec<A>>, source_opt: Option<Vec<A>>) -> Option<Vec<A>> {
match (target_opt, source_opt) {
(Some(mut target), Some(mut source)) => {
target.reserve(source.len());
for op in source.drain(..) {
target.push(op);
}
Some(target)
},
(Some(v), None) | (None, Some(v)) => Some(v),
(None, None) => None,
}
}
fn chained_binops(kind: &ExprKind) -> Option<Vec<BinaryOp<'_>>> {
match kind {
ExprKind::Binary(_, left_outer, right_outer) => chained_binops_helper(left_outer, right_outer),
ExprKind::Paren(ref e) | ExprKind::Unary(_, ref e) => chained_binops(&e.kind),
_ => None,
}
}
fn chained_binops_helper(left_outer: &'expr Expr, right_outer: &'expr Expr) -> Option<Vec<BinaryOp<'expr>>> {
match (&left_outer.kind, &right_outer.kind) {
(
ExprKind::Paren(ref left_e) | ExprKind::Unary(_, ref left_e),
ExprKind::Paren(ref right_e) | ExprKind::Unary(_, ref right_e),
) => chained_binops_helper(left_e, right_e),
(ExprKind::Paren(ref left_e) | ExprKind::Unary(_, ref left_e), _) => chained_binops_helper(left_e, right_outer),
(_, ExprKind::Paren(ref right_e) | ExprKind::Unary(_, ref right_e)) => {
chained_binops_helper(left_outer, right_e)
},
(
ExprKind::Binary(Spanned { node: left_op, .. }, ref left_left, ref left_right),
ExprKind::Binary(Spanned { node: right_op, .. }, ref right_left, ref right_right),
) => match (
chained_binops_helper(left_left, left_right),
chained_binops_helper(right_left, right_right),
) {
(Some(mut left_ops), Some(mut right_ops)) => {
left_ops.reserve(right_ops.len());
for op in right_ops.drain(..) {
left_ops.push(op);
}
Some(left_ops)
},
(Some(mut left_ops), _) => {
left_ops.push(BinaryOp::new(*right_op, right_outer.span, (right_left, right_right)));
Some(left_ops)
},
(_, Some(mut right_ops)) => {
right_ops.insert(0, BinaryOp::new(*left_op, left_outer.span, (left_left, left_right)));
Some(right_ops)
},
(None, None) => Some(vec![
BinaryOp::new(*left_op, left_outer.span, (left_left, left_right)),
BinaryOp::new(*right_op, right_outer.span, (right_left, right_right)),
]),
},
_ => None,
}
}
#[derive(Clone, Copy, PartialEq, Eq, Default, Debug)]
struct IdentLocation {
index: usize,
}
impl Add for IdentLocation {
type Output = IdentLocation;
fn add(self, other: Self) -> Self::Output {
Self {
index: self.index + other.index,
}
}
}
impl AddAssign for IdentLocation {
fn add_assign(&mut self, other: Self) {
*self = *self + other
}
}
#[derive(Clone, Copy, Debug)]
enum IdentDifference {
NoDifference,
Single(IdentLocation),
Double(IdentLocation, IdentLocation),
Multiple,
NonIdent,
}
impl Add for IdentDifference {
type Output = IdentDifference;
fn add(self, other: Self) -> Self::Output {
match (self, other) {
(Self::NoDifference, output) | (output, Self::NoDifference) => output,
(Self::Multiple, _)
| (_, Self::Multiple)
| (Self::Double(_, _), Self::Single(_))
| (Self::Single(_) | Self::Double(_, _), Self::Double(_, _)) => Self::Multiple,
(Self::NonIdent, _) | (_, Self::NonIdent) => Self::NonIdent,
(Self::Single(il1), Self::Single(il2)) => Self::Double(il1, il2),
}
}
}
impl AddAssign for IdentDifference {
fn add_assign(&mut self, other: Self) {
*self = *self + other
}
}
impl IdentDifference {
/// Returns true if learning about more differences will not change the value
/// of this `IdentDifference`, and false otherwise.
fn is_complete(&self) -> bool {
match self {
Self::NoDifference | Self::Single(_) | Self::Double(_, _) => false,
Self::Multiple | Self::NonIdent => true,
}
}
}
fn ident_difference_expr(left: &Expr, right: &Expr) -> IdentDifference {
ident_difference_expr_with_base_location(left, right, IdentLocation::default()).0
}
fn ident_difference_expr_with_base_location(
left: &Expr,
right: &Expr,
mut base: IdentLocation,
) -> (IdentDifference, IdentLocation) {
// Ideally, this function should not use IdentIter because it should return
// early if the expressions have any non-ident differences. We want that early
// return because if without that restriction the lint would lead to false
// positives.
//
// But, we cannot (easily?) use a `rustc_ast::visit::Visitor`, since we need
// the two expressions to be walked in lockstep. And without a `Visitor`, we'd
// have to do all the AST traversal ourselves, which is a lot of work, since to
// do it properly we'd need to be able to handle more or less every possible
// AST node since `Item`s can be written inside `Expr`s.
//
// In practice, it seems likely that expressions, above a certain size, that
// happen to use the exact same idents in the exact same order, and which are
// not structured the same, would be rare. Therefore it seems likely that if
// we do only the first layer of matching ourselves and eventually fallback on
// IdentIter, then the output of this function will be almost always be correct
// in practice.
//
// If it turns out that problematic cases are more prelavent than we assume,
// then we should be able to change this function to do the correct traversal,
// without needing to change the rest of the code.
#![allow(clippy::enum_glob_use)]
use ExprKind::*;
match (
&strip_non_ident_wrappers(left).kind,
&strip_non_ident_wrappers(right).kind,
) {
(Yield(_), Yield(_))
| (Try(_), Try(_))
| (Paren(_), Paren(_))
| (Repeat(_, _), Repeat(_, _))
| (Struct(_, _, _), Struct(_, _, _))
| (MacCall(_), MacCall(_))
| (LlvmInlineAsm(_), LlvmInlineAsm(_))
| (InlineAsm(_), InlineAsm(_))
| (Ret(_), Ret(_))
| (Continue(_), Continue(_))
| (Break(_, _), Break(_, _))
| (AddrOf(_, _, _), AddrOf(_, _, _))
| (Path(_, _), Path(_, _))
| (Range(_, _, _), Range(_, _, _))
| (Index(_, _), Index(_, _))
| (Field(_, _), Field(_, _))
| (AssignOp(_, _, _), AssignOp(_, _, _))
| (Assign(_, _, _), Assign(_, _, _))
| (TryBlock(_), TryBlock(_))
| (Await(_), Await(_))
| (Async(_, _, _), Async(_, _, _))
| (Block(_, _), Block(_, _))
| (Closure(_, _, _, _, _, _), Closure(_, _, _, _, _, _))
| (Match(_, _), Match(_, _))
| (Loop(_, _), Loop(_, _))
| (ForLoop(_, _, _, _), ForLoop(_, _, _, _))
| (While(_, _, _), While(_, _, _))
| (If(_, _, _), If(_, _, _))
| (Let(_, _), Let(_, _))
| (Type(_, _), Type(_, _))
| (Cast(_, _), Cast(_, _))
| (Lit(_), Lit(_))
| (Unary(_, _), Unary(_, _))
| (Binary(_, _, _), Binary(_, _, _))
| (Tup(_), Tup(_))
| (MethodCall(_, _, _), MethodCall(_, _, _))
| (Call(_, _), Call(_, _))
| (ConstBlock(_), ConstBlock(_))
| (Array(_), Array(_))
| (Box(_), Box(_)) => {
// keep going
},
_ => {
return (IdentDifference::NonIdent, base);
},
}
let mut difference = IdentDifference::NoDifference;
for (left_attr, right_attr) in left.attrs.iter().zip(right.attrs.iter()) {
let (new_difference, new_base) =
ident_difference_via_ident_iter_with_base_location(left_attr, right_attr, base);
base = new_base;
difference += new_difference;
if difference.is_complete() {
return (difference, base);
}
}
let (new_difference, new_base) = ident_difference_via_ident_iter_with_base_location(left, right, base);
base = new_base;
difference += new_difference;
(difference, base)
}
fn ident_difference_via_ident_iter_with_base_location<Iterable: Into<IdentIter>>(
left: Iterable,
right: Iterable,
mut base: IdentLocation,
) -> (IdentDifference, IdentLocation) {
// See the note in `ident_difference_expr_with_base_location` about `IdentIter`
let mut difference = IdentDifference::NoDifference;
let mut left_iterator = left.into();
let mut right_iterator = right.into();
loop {
match (left_iterator.next(), right_iterator.next()) {
(Some(left_ident), Some(right_ident)) => {
if !eq_id(left_ident, right_ident) {
difference += IdentDifference::Single(base);
if difference.is_complete() {
return (difference, base);
}
}
},
(Some(_), None) | (None, Some(_)) => {
return (IdentDifference::NonIdent, base);
},
(None, None) => {
return (difference, base);
},
}
base += IdentLocation { index: 1 };
}
}
fn get_ident(expr: &Expr, location: IdentLocation) -> Option<Ident> {
IdentIter::from(expr).nth(location.index)
}
fn suggestion_with_swapped_ident(
cx: &EarlyContext<'_>,
expr: &Expr,
location: IdentLocation,
new_ident: Ident,
applicability: &mut Applicability,
) -> Option<String> {
get_ident(expr, location).and_then(|current_ident| {
if eq_id(current_ident, new_ident) {
// We never want to suggest a non-change
return None;
}
Some(format!(
"{}{}{}",
snippet_with_applicability(cx, expr.span.with_hi(current_ident.span.lo()), "..", applicability),
new_ident.to_string(),
snippet_with_applicability(cx, expr.span.with_lo(current_ident.span.hi()), "..", applicability),
))
})
}
fn skip_index<A, Iter>(iter: Iter, index: usize) -> impl Iterator<Item = A>
where
Iter: Iterator<Item = A>,
{
iter.enumerate()
.filter_map(move |(i, a)| if i == index { None } else { Some(a) })
}

3
clippy_lints/src/trait_bounds.rs
View file

@ -168,8 +168,7 @@ fn check_trait_bound_duplication(cx: &LateContext<'_>, gen: &'_ Generics<'_>) {
if_chain! {
if let WherePredicate::BoundPredicate(ref bound_predicate) = predicate;
if !in_macro(bound_predicate.span);
if let TyKind::Path(ref path) = bound_predicate.bounded_ty.kind;
if let QPath::Resolved(_, Path { ref segments, .. }) = path;
if let TyKind::Path(QPath::Resolved(_, Path { ref segments, .. })) = bound_predicate.bounded_ty.kind;
if let Some(segment) = segments.first();
if let Some(trait_resolutions_direct) = map.get(&segment.ident);
then {

3
clippy_lints/src/transmuting_null.rs
View file

@ -48,8 +48,7 @@ impl<'tcx> LateLintPass<'tcx> for TransmutingNull {
if_chain! {
if let ExprKind::Path(ref _qpath) = args[0].kind;
let x = const_eval_context.expr(&args[0]);
if let Some(constant) = x;
if let Constant::RawPtr(0) = constant;
if let Some(Constant::RawPtr(0)) = x;
then {
span_lint(cx, TRANSMUTING_NULL, expr.span, LINT_MSG)
}

18
clippy_lints/src/types.rs
View file

@ -8,6 +8,7 @@ use if_chain::if_chain;
use rustc_ast::{FloatTy, IntTy, LitFloatType, LitIntType, LitKind, UintTy};
use rustc_errors::{Applicability, DiagnosticBuilder};
use rustc_hir as hir;
use rustc_hir::def::Res;
use rustc_hir::intravisit::{walk_body, walk_expr, walk_ty, FnKind, NestedVisitorMap, Visitor};
use rustc_hir::{
BinOpKind, Block, Body, Expr, ExprKind, FnDecl, FnRetTy, FnSig, GenericArg, GenericBounds, GenericParamKind, HirId,
@ -737,8 +738,7 @@ fn is_any_trait(t: &hir::Ty<'_>) -> bool {
fn get_bounds_if_impl_trait<'tcx>(cx: &LateContext<'tcx>, qpath: &QPath<'_>, id: HirId) -> Option<GenericBounds<'tcx>> {
if_chain! {
if let Some(did) = qpath_res(cx, qpath, id).opt_def_id();
if let Some(node) = cx.tcx.hir().get_if_local(did);
if let Node::GenericParam(generic_param) = node;
if let Some(Node::GenericParam(generic_param)) = cx.tcx.hir().get_if_local(did);
if let GenericParamKind::Type { synthetic, .. } = generic_param.kind;
if synthetic == Some(SyntheticTyParamKind::ImplTrait);
then {
@ -1469,8 +1469,7 @@ fn check_loss_of_sign(cx: &LateContext<'_>, expr: &Expr<'_>, op: &Expr<'_>, cast
// don't lint for positive constants
let const_val = constant(cx, &cx.typeck_results(), op);
if_chain! {
if let Some((const_val, _)) = const_val;
if let Constant::Int(n) = const_val;
if let Some((Constant::Int(n), _)) = const_val;
if let ty::Int(ity) = *cast_from.kind();
if sext(cx.tcx, n, ity) >= 0;
then {
@ -1632,7 +1631,14 @@ impl<'tcx> LateLintPass<'tcx> for Casts {
if expr.span.from_expansion() {
return;
}
if let ExprKind::Cast(ref ex, _) = expr.kind {
if let ExprKind::Cast(ref ex, cast_to) = expr.kind {
if let TyKind::Path(QPath::Resolved(_, path)) = cast_to.kind {
if let Res::Def(_, def_id) = path.res {
if cx.tcx.has_attr(def_id, sym::cfg) || cx.tcx.has_attr(def_id, sym::cfg_attr) {
return;
}
}
}
let (cast_from, cast_to) = (cx.typeck_results().expr_ty(ex), cx.typeck_results().expr_ty(expr));
lint_fn_to_numeric_cast(cx, expr, ex, cast_from, cast_to);
if let Some(lit) = get_numeric_literal(ex) {
@ -1711,7 +1717,7 @@ fn show_unnecessary_cast(cx: &LateContext<'_>, expr: &Expr<'_>, literal_str: &st
expr.span,
&format!("casting {} literal to `{}` is unnecessary", literal_kind_name, cast_to),
"try",
format!("{}_{}", literal_str, cast_to),
format!("{}_{}", literal_str.trim_end_matches('.'), cast_to),
Applicability::MachineApplicable,
);
}

5
clippy_lints/src/unnecessary_wraps.rs
View file

@ -1,5 +1,5 @@
use crate::utils::{
in_macro, is_type_diagnostic_item, match_qpath, paths, return_ty, snippet, span_lint_and_then,
contains_return, in_macro, is_type_diagnostic_item, match_qpath, paths, return_ty, snippet, span_lint_and_then,
visitors::find_all_ret_expressions,
};
use if_chain::if_chain;
@ -95,6 +95,7 @@ impl<'tcx> LateLintPass<'tcx> for UnnecessaryWraps {
if let ExprKind::Path(ref qpath) = func.kind;
if match_qpath(qpath, path);
if args.len() == 1;
if !contains_return(&args[0]);
then {
suggs.push((ret_expr.span, snippet(cx, args[0].span.source_callsite(), "..").to_string()));
true
@ -134,7 +135,7 @@ impl<'tcx> LateLintPass<'tcx> for UnnecessaryWraps {
diag.multipart_suggestion(
"...and change the returning expressions",
suggs,
Applicability::MachineApplicable,
Applicability::MaybeIncorrect,
);
},
);

11
clippy_lints/src/utils/ast_utils.rs
View file

@ -10,6 +10,17 @@ use rustc_ast::{self as ast, *};
use rustc_span::symbol::Ident;
use std::mem;
pub mod ident_iter;
pub use ident_iter::IdentIter;
pub fn is_useless_with_eq_exprs(kind: BinOpKind) -> bool {
use BinOpKind::*;
matches!(
kind,
Sub | Div | Eq | Lt | Le | Gt | Ge | Ne | And | Or | BitXor | BitAnd | BitOr
)
}
/// Checks if each element in the first slice is contained within the latter as per `eq_fn`.
pub fn unordered_over<X>(left: &[X], right: &[X], mut eq_fn: impl FnMut(&X, &X) -> bool) -> bool {
left.len() == right.len() && left.iter().all(|l| right.iter().any(|r| eq_fn(l, r)))

45
clippy_lints/src/utils/ast_utils/ident_iter.rs Normal file
View file

@ -0,0 +1,45 @@
use core::iter::FusedIterator;
use rustc_ast::visit::{walk_attribute, walk_expr, Visitor};
use rustc_ast::{Attribute, Expr};
use rustc_span::symbol::Ident;
pub struct IdentIter(std::vec::IntoIter<Ident>);
impl Iterator for IdentIter {
type Item = Ident;
fn next(&mut self) -> Option<Self::Item> {
self.0.next()
}
}
impl FusedIterator for IdentIter {}
impl From<&Expr> for IdentIter {
fn from(expr: &Expr) -> Self {
let mut visitor = IdentCollector::default();
walk_expr(&mut visitor, expr);
IdentIter(visitor.0.into_iter())
}
}
impl From<&Attribute> for IdentIter {
fn from(attr: &Attribute) -> Self {
let mut visitor = IdentCollector::default();
walk_attribute(&mut visitor, attr);
IdentIter(visitor.0.into_iter())
}
}
#[derive(Default)]
struct IdentCollector(Vec<Ident>);
impl Visitor<'_> for IdentCollector {
fn visit_ident(&mut self, ident: Ident) {
self.0.push(ident);
}
}

19
clippy_lints/src/utils/attrs.rs
View file

@ -21,6 +21,7 @@ pub const BUILTIN_ATTRIBUTES: &[(&str, DeprecationStatus)] = &[
DeprecationStatus::Replaced("cognitive_complexity"),
),
("dump", DeprecationStatus::None),
("msrv", DeprecationStatus::None),
];
pub struct LimitStack {
@ -123,6 +124,24 @@ fn parse_attrs<F: FnMut(u64)>(sess: &Session, attrs: &[ast::Attribute], name: &'
}
}
pub fn get_unique_inner_attr(sess: &Session, attrs: &[ast::Attribute], name: &'static str) -> Option<ast::Attribute> {
let mut unique_attr = None;
for attr in get_attr(sess, attrs, name) {
match attr.style {
ast::AttrStyle::Inner if unique_attr.is_none() => unique_attr = Some(attr.clone()),
ast::AttrStyle::Inner => {
sess.struct_span_err(attr.span, &format!("`{}` is defined multiple times", name))
.span_note(unique_attr.as_ref().unwrap().span, "first definition found here")
.emit();
},
ast::AttrStyle::Outer => {
sess.span_err(attr.span, &format!("`{}` cannot be an outer attribute", name));
},
}
}
unique_attr
}
/// Return true if the attributes contain any of `proc_macro`,
/// `proc_macro_derive` or `proc_macro_attribute`, false otherwise
pub fn is_proc_macro(sess: &Session, attrs: &[ast::Attribute]) -> bool {

4
clippy_lints/src/utils/conf.rs
View file

@ -106,6 +106,8 @@ macro_rules! define_Conf {
pub use self::helpers::Conf;
define_Conf! {
/// Lint: MANUAL_NON_EXHAUSTIVE, MANUAL_STRIP, OPTION_AS_REF_DEREF, MATCH_LIKE_MATCHES_MACRO. The minimum rust version that the project supports
(msrv, "msrv": Option<String>, None),
/// Lint: BLACKLISTED_NAME. The list of blacklisted names to lint about. NB: `bar` is not here since it has legitimate uses
(blacklisted_names, "blacklisted_names": Vec<String>, ["foo", "baz", "quux"].iter().map(ToString::to_string).collect()),
/// Lint: COGNITIVE_COMPLEXITY. The maximum cognitive complexity a function can have
@ -168,6 +170,8 @@ define_Conf! {
(warn_on_all_wildcard_imports, "warn_on_all_wildcard_imports": bool, false),
/// Lint: DISALLOWED_METHOD. The list of blacklisted methods to lint about. NB: `bar` is not here since it has legitimate uses
(disallowed_methods, "disallowed_methods": Vec<String>, Vec::<String>::new()),
/// Lint: UNREADABLE_LITERAL. Should the fraction of a decimal be linted to include separators.
(unreadable_literal_lint_fractions, "unreadable_literal_lint_fractions": bool, true),
}
impl Default for Conf {

4
clippy_lints/src/utils/diagnostics.rs
View file

@ -186,7 +186,9 @@ pub fn span_lint_hir_and_then(
/// |
/// = note: `-D fold-any` implied by `-D warnings`
/// ```
#[allow(clippy::collapsible_span_lint_calls)]
#[allow(clippy::unknown_clippy_lints)]
#[cfg_attr(feature = "internal-lints", allow(clippy::collapsible_span_lint_calls))]
pub fn span_lint_and_sugg<'a, T: LintContext>(
cx: &'a T,
lint: &'static Lint,

3
clippy_lints/src/utils/higher.rs
View file

@ -162,8 +162,7 @@ pub fn while_loop<'tcx>(expr: &'tcx hir::Expr<'tcx>) -> Option<(&'tcx hir::Expr<
if let hir::Block { expr: Some(expr), .. } = &**block;
if let hir::ExprKind::Match(cond, arms, hir::MatchSource::WhileDesugar) = &expr.kind;
if let hir::ExprKind::DropTemps(cond) = &cond.kind;
if let [arm, ..] = &arms[..];
if let hir::Arm { body, .. } = arm;
if let [hir::Arm { body, .. }, ..] = &arms[..];
then {
return Some((cond, body));
}

28
clippy_lints/src/utils/hir_utils.rs
View file

@ -81,7 +81,7 @@ impl<'a, 'tcx> SpanlessEq<'a, 'tcx> {
}
}
match (&left.kind, &right.kind) {
match (&reduce_exprkind(&left.kind), &reduce_exprkind(&right.kind)) {
(&ExprKind::AddrOf(lb, l_mut, ref le), &ExprKind::AddrOf(rb, r_mut, ref re)) => {
lb == rb && l_mut == r_mut && self.eq_expr(le, re)
},
@ -306,6 +306,32 @@ impl<'a, 'tcx> SpanlessEq<'a, 'tcx> {
}
}
/// Some simple reductions like `{ return }` => `return`
fn reduce_exprkind<'hir>(kind: &'hir ExprKind<'hir>) -> &ExprKind<'hir> {
if let ExprKind::Block(block, _) = kind {
match (block.stmts, block.expr) {
// `{}` => `()`
([], None) => &ExprKind::Tup(&[]),
([], Some(expr)) => match expr.kind {
// `{ return .. }` => `return ..`
ExprKind::Ret(..) => &expr.kind,
_ => kind,
},
([stmt], None) => match stmt.kind {
StmtKind::Expr(expr) | StmtKind::Semi(expr) => match expr.kind {
// `{ return ..; }` => `return ..`
ExprKind::Ret(..) => &expr.kind,
_ => kind,
},
_ => kind,
},
_ => kind,
}
} else {
kind
}
}
fn swap_binop<'a>(
binop: BinOpKind,
lhs: &'a Expr<'a>,

76
clippy_lints/src/utils/mod.rs
View file

@ -14,6 +14,7 @@ pub mod eager_or_lazy;
pub mod higher;
mod hir_utils;
pub mod inspector;
#[cfg(feature = "internal-lints")]
pub mod internal_lints;
pub mod numeric_literal;
pub mod paths;
@ -51,6 +52,8 @@ use rustc_lint::{LateContext, Level, Lint, LintContext};
use rustc_middle::hir::map::Map;
use rustc_middle::ty::subst::{GenericArg, GenericArgKind};
use rustc_middle::ty::{self, layout::IntegerExt, Ty, TyCtxt, TypeFoldable};
use rustc_semver::RustcVersion;
use rustc_session::Session;
use rustc_span::hygiene::{ExpnKind, MacroKind};
use rustc_span::source_map::original_sp;
use rustc_span::sym as rustc_sym;
@ -62,6 +65,49 @@ use smallvec::SmallVec;
use crate::consts::{constant, Constant};
pub fn parse_msrv(msrv: &str, sess: Option<&Session>, span: Option<Span>) -> Option<RustcVersion> {
if let Ok(version) = RustcVersion::parse(msrv) {
return Some(version);
} else if let Some(sess) = sess {
if let Some(span) = span {
sess.span_err(span, &format!("`{}` is not a valid Rust version", msrv));
}
}
None
}
pub fn meets_msrv(msrv: Option<&RustcVersion>, lint_msrv: &RustcVersion) -> bool {
msrv.map_or(true, |msrv| msrv.meets(*lint_msrv))
}
macro_rules! extract_msrv_attr {
(LateContext) => {
extract_msrv_attr!(@LateContext, ());
};
(EarlyContext) => {
extract_msrv_attr!(@EarlyContext);
};
(@$context:ident$(, $call:tt)?) => {
fn enter_lint_attrs(&mut self, cx: &rustc_lint::$context<'tcx>, attrs: &'tcx [rustc_ast::ast::Attribute]) {
use $crate::utils::get_unique_inner_attr;
match get_unique_inner_attr(cx.sess$($call)?, attrs, "msrv") {
Some(msrv_attr) => {
if let Some(msrv) = msrv_attr.value_str() {
self.msrv = $crate::utils::parse_msrv(
&msrv.to_string(),
Some(cx.sess$($call)?),
Some(msrv_attr.span),
);
} else {
cx.sess$($call)?.span_err(msrv_attr.span, "bad clippy attribute");
}
},
_ => (),
}
}
};
}
/// Returns `true` if the two spans come from differing expansions (i.e., one is
/// from a macro and one isn't).
#[must_use]
@ -527,6 +573,36 @@ pub fn contains_name(name: Symbol, expr: &Expr<'_>) -> bool {
cn.result
}
/// Returns `true` if `expr` contains a return expression
pub fn contains_return(expr: &hir::Expr<'_>) -> bool {
struct RetCallFinder {
found: bool,
}
impl<'tcx> hir::intravisit::Visitor<'tcx> for RetCallFinder {
type Map = Map<'tcx>;
fn visit_expr(&mut self, expr: &'tcx hir::Expr<'_>) {
if self.found {
return;
}
if let hir::ExprKind::Ret(..) = &expr.kind {
self.found = true;
} else {
hir::intravisit::walk_expr(self, expr);
}
}
fn nested_visit_map(&mut self) -> hir::intravisit::NestedVisitorMap<Self::Map> {
hir::intravisit::NestedVisitorMap::None
}
}
let mut visitor = RetCallFinder { found: false };
visitor.visit_expr(expr);
visitor.found
}
/// Converts a span to a code snippet if available, otherwise use default.
///
/// This is useful if you want to provide suggestions for your lint or more generally, if you want

18
clippy_lints/src/utils/paths.rs
View file

@ -20,6 +20,8 @@ pub const CLONE_TRAIT: [&str; 3] = ["core", "clone", "Clone"];
pub const CLONE_TRAIT_METHOD: [&str; 4] = ["core", "clone", "Clone", "clone"];
pub const CMP_MAX: [&str; 3] = ["core", "cmp", "max"];
pub const CMP_MIN: [&str; 3] = ["core", "cmp", "min"];
pub const COPY: [&str; 3] = ["core", "intrinsics", "copy_nonoverlapping"];
pub const COPY_NONOVERLAPPING: [&str; 3] = ["core", "intrinsics", "copy"];
pub const COW: [&str; 3] = ["alloc", "borrow", "Cow"];
pub const CSTRING_AS_C_STR: [&str; 5] = ["std", "ffi", "c_str", "CString", "as_c_str"];
pub const DEFAULT_TRAIT: [&str; 3] = ["core", "default", "Default"];
@ -31,6 +33,7 @@ pub const DISPLAY_TRAIT: [&str; 3] = ["core", "fmt", "Display"];
pub const DOUBLE_ENDED_ITERATOR: [&str; 4] = ["core", "iter", "traits", "DoubleEndedIterator"];
pub const DROP: [&str; 3] = ["core", "mem", "drop"];
pub const DURATION: [&str; 3] = ["core", "time", "Duration"];
#[cfg(feature = "internal-lints")]
pub const EARLY_CONTEXT: [&str; 2] = ["rustc_lint", "EarlyContext"];
pub const EXIT: [&str; 3] = ["std", "process", "exit"];
pub const F32_EPSILON: [&str; 4] = ["core", "f32", "<impl f32>", "EPSILON"];
@ -58,9 +61,13 @@ pub const INTO: [&str; 3] = ["core", "convert", "Into"];
pub const INTO_ITERATOR: [&str; 5] = ["core", "iter", "traits", "collect", "IntoIterator"];
pub const IO_READ: [&str; 3] = ["std", "io", "Read"];
pub const IO_WRITE: [&str; 3] = ["std", "io", "Write"];
pub const IPADDR_V4: [&str; 4] = ["std", "net", "IpAddr", "V4"];
pub const IPADDR_V6: [&str; 4] = ["std", "net", "IpAddr", "V6"];
pub const ITERATOR: [&str; 5] = ["core", "iter", "traits", "iterator", "Iterator"];
#[cfg(feature = "internal-lints")]
pub const LATE_CONTEXT: [&str; 2] = ["rustc_lint", "LateContext"];
pub const LINKED_LIST: [&str; 4] = ["alloc", "collections", "linked_list", "LinkedList"];
#[cfg(feature = "internal-lints")]
pub const LINT: [&str; 2] = ["rustc_lint_defs", "Lint"];
pub const MEM_DISCRIMINANT: [&str; 3] = ["core", "mem", "discriminant"];
pub const MEM_FORGET: [&str; 3] = ["core", "mem", "forget"];
@ -68,6 +75,8 @@ pub const MEM_MANUALLY_DROP: [&str; 4] = ["core", "mem", "manually_drop", "Manua
pub const MEM_MAYBEUNINIT: [&str; 4] = ["core", "mem", "maybe_uninit", "MaybeUninit"];
pub const MEM_MAYBEUNINIT_UNINIT: [&str; 5] = ["core", "mem", "maybe_uninit", "MaybeUninit", "uninit"];
pub const MEM_REPLACE: [&str; 3] = ["core", "mem", "replace"];
pub const MEM_SIZE_OF: [&str; 3] = ["core", "mem", "size_of"];
pub const MEM_SIZE_OF_VAL: [&str; 3] = ["core", "mem", "size_of_val"];
pub const MUTEX_GUARD: [&str; 4] = ["std", "sync", "mutex", "MutexGuard"];
pub const OPEN_OPTIONS: [&str; 3] = ["std", "fs", "OpenOptions"];
pub const OPS_MODULE: [&str; 2] = ["core", "ops"];
@ -90,9 +99,14 @@ pub const PATH_BUF: [&str; 3] = ["std", "path", "PathBuf"];
pub const PATH_BUF_AS_PATH: [&str; 4] = ["std", "path", "PathBuf", "as_path"];
pub const PATH_TO_PATH_BUF: [&str; 4] = ["std", "path", "Path", "to_path_buf"];
pub const POLL: [&str; 4] = ["core", "task", "poll", "Poll"];
pub const POLL_PENDING: [&str; 5] = ["core", "task", "poll", "Poll", "Pending"];
pub const POLL_READY: [&str; 5] = ["core", "task", "poll", "Poll", "Ready"];
pub const PTR_EQ: [&str; 3] = ["core", "ptr", "eq"];
pub const PTR_NULL: [&str; 3] = ["core", "ptr", "null"];
pub const PTR_NULL_MUT: [&str; 3] = ["core", "ptr", "null_mut"];
pub const PTR_SLICE_FROM_RAW_PARTS: [&str; 3] = ["core", "ptr", "slice_from_raw_parts"];
pub const PTR_SLICE_FROM_RAW_PARTS_MUT: [&str; 3] = ["core", "ptr", "slice_from_raw_parts_mut"];
pub const PTR_SWAP_NONOVERLAPPING: [&str; 3] = ["core", "ptr", "swap_nonoverlapping"];
pub const PUSH_STR: [&str; 4] = ["alloc", "string", "String", "push_str"];
pub const RANGE_ARGUMENT_TRAIT: [&str; 3] = ["core", "ops", "RangeBounds"];
pub const RC: [&str; 3] = ["alloc", "rc", "Rc"];
@ -114,6 +128,8 @@ pub const RWLOCK_READ_GUARD: [&str; 4] = ["std", "sync", "rwlock", "RwLockReadGu
pub const RWLOCK_WRITE_GUARD: [&str; 4] = ["std", "sync", "rwlock", "RwLockWriteGuard"];
pub const SERDE_DESERIALIZE: [&str; 3] = ["serde", "de", "Deserialize"];
pub const SERDE_DE_VISITOR: [&str; 3] = ["serde", "de", "Visitor"];
pub const SLICE_FROM_RAW_PARTS: [&str; 4] = ["core", "slice", "raw", "from_raw_parts"];
pub const SLICE_FROM_RAW_PARTS_MUT: [&str; 4] = ["core", "slice", "raw", "from_raw_parts_mut"];
pub const SLICE_INTO_VEC: [&str; 4] = ["alloc", "slice", "<impl [T]>", "into_vec"];
pub const SLICE_ITER: [&str; 4] = ["core", "slice", "iter", "Iter"];
pub const STDERR: [&str; 4] = ["std", "io", "stdio", "stderr"];
@ -129,6 +145,7 @@ pub const STR_ENDS_WITH: [&str; 4] = ["core", "str", "<impl str>", "ends_with"];
pub const STR_FROM_UTF8: [&str; 4] = ["core", "str", "converts", "from_utf8"];
pub const STR_LEN: [&str; 4] = ["core", "str", "<impl str>", "len"];
pub const STR_STARTS_WITH: [&str; 4] = ["core", "str", "<impl str>", "starts_with"];
#[cfg(feature = "internal-lints")]
pub const SYNTAX_CONTEXT: [&str; 3] = ["rustc_span", "hygiene", "SyntaxContext"];
pub const TO_OWNED: [&str; 3] = ["alloc", "borrow", "ToOwned"];
pub const TO_OWNED_METHOD: [&str; 4] = ["alloc", "borrow", "ToOwned", "to_owned"];
@ -146,3 +163,4 @@ pub const VEC_NEW: [&str; 4] = ["alloc", "vec", "Vec", "new"];
pub const VEC_RESIZE: [&str; 4] = ["alloc", "vec", "Vec", "resize"];
pub const WEAK_ARC: [&str; 3] = ["alloc", "sync", "Weak"];
pub const WEAK_RC: [&str; 3] = ["alloc", "rc", "Weak"];
pub const WRITE_BYTES: [&str; 3] = ["core", "intrinsics", "write_bytes"];

55
clippy_lints/src/utils/visitors.rs
View file

@ -1,5 +1,7 @@
use rustc_hir as hir;
use rustc_hir::intravisit::{self, Visitor};
use rustc_hir::def::Res;
use rustc_hir::intravisit::{self, walk_expr, NestedVisitorMap, Visitor};
use rustc_hir::{Arm, Expr, ExprKind, HirId, QPath, Stmt};
use rustc_lint::LateContext;
use rustc_middle::hir::map::Map;
@ -123,3 +125,54 @@ where
!ret_finder.failed
}
}
pub struct LocalUsedVisitor {
pub local_hir_id: HirId,
pub used: bool,
}
impl LocalUsedVisitor {
pub fn new(local_hir_id: HirId) -> Self {
Self {
local_hir_id,
used: false,
}
}
fn check<T>(&mut self, t: T, visit: fn(&mut Self, T)) -> bool {
visit(self, t);
std::mem::replace(&mut self.used, false)
}
pub fn check_arm(&mut self, arm: &Arm<'_>) -> bool {
self.check(arm, Self::visit_arm)
}
pub fn check_expr(&mut self, expr: &Expr<'_>) -> bool {
self.check(expr, Self::visit_expr)
}
pub fn check_stmt(&mut self, stmt: &Stmt<'_>) -> bool {
self.check(stmt, Self::visit_stmt)
}
}
impl<'v> Visitor<'v> for LocalUsedVisitor {
type Map = Map<'v>;
fn visit_expr(&mut self, expr: &'v Expr<'v>) {
if let ExprKind::Path(QPath::Resolved(None, path)) = expr.kind {
if let Res::Local(id) = path.res {
if id == self.local_hir_id {
self.used = true;
return;
}
}
}
walk_expr(self, expr);
}
fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
NestedVisitorMap::None
}
}