// (Currently there is no way to opt into sysroot crates without `extern crate`.)
extern crate rustc_ast;
extern crate rustc_ast_pretty;
+extern crate rustc_attr;
extern crate rustc_data_structures;
extern crate rustc_errors;
extern crate rustc_hir;
pub mod eager_or_lazy;
pub mod higher;
mod hir_utils;
+pub mod msrvs;
pub mod numeric_literal;
pub mod paths;
pub mod ptr;
use rustc_ast::ast::{self, Attribute, BorrowKind, LitKind};
use rustc_data_structures::fx::FxHashMap;
use rustc_hir as hir;
-use rustc_hir::def::{CtorKind, CtorOf, DefKind, Res};
+use rustc_hir::def::{DefKind, Res};
use rustc_hir::def_id::{DefId, LOCAL_CRATE};
-use rustc_hir::intravisit::{self, NestedVisitorMap, Visitor};
+use rustc_hir::intravisit::{self, walk_expr, ErasedMap, NestedVisitorMap, Visitor};
+use rustc_hir::LangItem::{ResultErr, ResultOk};
use rustc_hir::{
- def, Arm, BindingAnnotation, Block, Body, Constness, Expr, ExprKind, FnDecl, GenericArgs, HirId, Impl, ImplItem,
- ImplItemKind, Item, ItemKind, LangItem, MatchSource, Node, Param, Pat, PatKind, Path, PathSegment, QPath,
- TraitItem, TraitItemKind, TraitRef, TyKind,
+ def, Arm, BindingAnnotation, Block, Body, Constness, Destination, Expr, ExprKind, FnDecl, GenericArgs, HirId, Impl,
+ ImplItem, ImplItemKind, Item, ItemKind, LangItem, Local, MatchSource, Node, Param, Pat, PatKind, Path, PathSegment,
+ QPath, Stmt, StmtKind, TraitItem, TraitItemKind, TraitRef, TyKind,
};
use rustc_lint::{LateContext, Level, Lint, LintContext};
use rustc_middle::hir::exports::Export;
use rustc_target::abi::Integer;
use crate::consts::{constant, Constant};
-use crate::ty::is_recursively_primitive_type;
+use crate::ty::{can_partially_move_ty, is_recursively_primitive_type};
pub fn parse_msrv(msrv: &str, sess: Option<&Session>, span: Option<Span>) -> Option<RustcVersion> {
if let Ok(version) = RustcVersion::parse(msrv) {
}
}
+/// Checks if a `QPath` resolves to a constructor of a `LangItem`.
+/// For example, use this to check whether a function call or a pattern is `Some(..)`.
+pub fn is_lang_ctor(cx: &LateContext<'_>, qpath: &QPath<'_>, lang_item: LangItem) -> bool {
+ if let QPath::Resolved(_, path) = qpath {
+ if let Res::Def(DefKind::Ctor(..), ctor_id) = path.res {
+ if let Ok(item_id) = cx.tcx.lang_items().require(lang_item) {
+ return cx.tcx.parent(ctor_id) == Some(item_id);
+ }
+ }
+ }
+ false
+}
+
/// Returns `true` if this `span` was expanded by any macro.
#[must_use]
pub fn in_macro(span: Span) -> bool {
trt_id.map_or(false, |trt_id| match_def_path(cx, trt_id, path))
}
-/// Checks if the method call given in `def_id` belongs to a trait or other container with a given
-/// diagnostic item
-pub fn is_diagnostic_assoc_item(cx: &LateContext<'_>, def_id: DefId, diag_item: Symbol) -> bool {
- cx.tcx
- .opt_associated_item(def_id)
- .and_then(|associated_item| match associated_item.container {
- rustc_ty::TraitContainer(assoc_def_id) => Some(assoc_def_id),
- rustc_ty::ImplContainer(assoc_def_id) => match cx.tcx.type_of(assoc_def_id).kind() {
- rustc_ty::Adt(adt, _) => Some(adt.did),
- rustc_ty::Slice(_) => cx.tcx.get_diagnostic_item(sym::slice), // this isn't perfect but it works
- _ => None,
- },
- })
- .map_or(false, |assoc_def_id| cx.tcx.is_diagnostic_item(diag_item, assoc_def_id))
+/// Checks if a method is defined in an impl of a diagnostic item
+pub fn is_diag_item_method(cx: &LateContext<'_>, def_id: DefId, diag_item: Symbol) -> bool {
+ if let Some(impl_did) = cx.tcx.impl_of_method(def_id) {
+ if let Some(adt) = cx.tcx.type_of(impl_did).ty_adt_def() {
+ return cx.tcx.is_diagnostic_item(diag_item, adt.did);
+ }
+ }
+ false
+}
+
+/// Checks if a method is in a diagnostic item trait
+pub fn is_diag_trait_item(cx: &LateContext<'_>, def_id: DefId, diag_item: Symbol) -> bool {
+ if let Some(trait_did) = cx.tcx.trait_of_item(def_id) {
+ return cx.tcx.is_diagnostic_item(diag_item, trait_did);
+ }
+ false
}
/// Checks if the method call given in `expr` belongs to the given trait.
pub fn is_trait_method(cx: &LateContext<'_>, expr: &Expr<'_>, diag_item: Symbol) -> bool {
cx.typeck_results()
.type_dependent_def_id(expr.hir_id)
- .map_or(false, |did| is_diagnostic_assoc_item(cx, did, diag_item))
+ .map_or(false, |did| is_diag_trait_item(cx, did, diag_item))
}
/// Checks if an expression references a variable of the given name.
}
}
+/// If the expression is a path, resolve it. Otherwise, return `Res::Err`.
+pub fn expr_path_res(cx: &LateContext<'_>, expr: &Expr<'_>) -> Res {
+ if let ExprKind::Path(p) = &expr.kind {
+ cx.qpath_res(p, expr.hir_id)
+ } else {
+ Res::Err
+ }
+}
+
+/// Resolves the path to a `DefId` and checks if it matches the given path.
+pub fn is_qpath_def_path(cx: &LateContext<'_>, path: &QPath<'_>, hir_id: HirId, segments: &[&str]) -> bool {
+ cx.qpath_res(path, hir_id)
+ .opt_def_id()
+ .map_or(false, |id| match_def_path(cx, id, segments))
+}
+
+/// If the expression is a path, resolves it to a `DefId` and checks if it matches the given path.
+pub fn is_expr_path_def_path(cx: &LateContext<'_>, expr: &Expr<'_>, segments: &[&str]) -> bool {
+ expr_path_res(cx, expr)
+ .opt_def_id()
+ .map_or(false, |id| match_def_path(cx, id, segments))
+}
+
/// THIS METHOD IS DEPRECATED and will eventually be removed since it does not match against the
/// entire path or resolved `DefId`. Prefer using `match_def_path`. Consider getting a `DefId` from
/// `QPath::Resolved.1.res.opt_def_id()`.
.all(|(a, b)| a.ident.name.as_str() == *b)
}
-/// Matches a `Path` against a slice of segment string literals, e.g.
-///
-/// # Examples
-/// ```rust,ignore
-/// match_path_ast(path, &["std", "rt", "begin_unwind"])
-/// ```
-pub fn match_path_ast(path: &ast::Path, segments: &[&str]) -> bool {
- path.segments
- .iter()
- .rev()
- .zip(segments.iter().rev())
- .all(|(a, b)| a.ident.name.as_str() == *b)
-}
-
/// If the expression is a path to a local, returns the canonical `HirId` of the local.
pub fn path_to_local(expr: &Expr<'_>) -> Option<HirId> {
if let ExprKind::Path(QPath::Resolved(None, ref path)) = expr.kind {
None
}
+/// Checks if the top level expression can be moved into a closure as is.
+pub fn can_move_expr_to_closure_no_visit(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>, jump_targets: &[HirId]) -> bool {
+ match expr.kind {
+ ExprKind::Break(Destination { target_id: Ok(id), .. }, _)
+ | ExprKind::Continue(Destination { target_id: Ok(id), .. })
+ if jump_targets.contains(&id) =>
+ {
+ true
+ },
+ ExprKind::Break(..)
+ | ExprKind::Continue(_)
+ | ExprKind::Ret(_)
+ | ExprKind::Yield(..)
+ | ExprKind::InlineAsm(_)
+ | ExprKind::LlvmInlineAsm(_) => false,
+ // Accessing a field of a local value can only be done if the type isn't
+ // partially moved.
+ ExprKind::Field(base_expr, _)
+ if matches!(
+ base_expr.kind,
+ ExprKind::Path(QPath::Resolved(_, Path { res: Res::Local(_), .. }))
+ ) && can_partially_move_ty(cx, cx.typeck_results().expr_ty(base_expr)) =>
+ {
+ // TODO: check if the local has been partially moved. Assume it has for now.
+ false
+ }
+ _ => true,
+ }
+}
+
+/// Checks if the expression can be moved into a closure as is.
+pub fn can_move_expr_to_closure(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) -> bool {
+ struct V<'cx, 'tcx> {
+ cx: &'cx LateContext<'tcx>,
+ loops: Vec<HirId>,
+ allow_closure: bool,
+ }
+ impl Visitor<'tcx> for V<'_, 'tcx> {
+ type Map = ErasedMap<'tcx>;
+ fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
+ NestedVisitorMap::None
+ }
+
+ fn visit_expr(&mut self, e: &'tcx Expr<'_>) {
+ if !self.allow_closure {
+ return;
+ }
+ if let ExprKind::Loop(b, ..) = e.kind {
+ self.loops.push(e.hir_id);
+ self.visit_block(b);
+ self.loops.pop();
+ } else {
+ self.allow_closure &= can_move_expr_to_closure_no_visit(self.cx, e, &self.loops);
+ walk_expr(self, e);
+ }
+ }
+ }
+
+ let mut v = V {
+ cx,
+ allow_closure: true,
+ loops: Vec::new(),
+ };
+ v.visit_expr(expr);
+ v.allow_closure
+}
+
/// Returns the method names and argument list of nested method call expressions that make up
/// `expr`. method/span lists are sorted with the most recent call first.
pub fn method_calls<'tcx>(
/// the function once on the given pattern.
pub fn recurse_or_patterns<'tcx, F: FnMut(&'tcx Pat<'tcx>)>(pat: &'tcx Pat<'tcx>, mut f: F) {
if let PatKind::Or(pats) = pat.kind {
- pats.iter().cloned().for_each(f)
+ pats.iter().copied().for_each(f)
} else {
f(pat)
}
/// Checks if a given expression is a match expression expanded from the `?`
/// operator or the `try` macro.
-pub fn is_try<'tcx>(expr: &'tcx Expr<'tcx>) -> Option<&'tcx Expr<'tcx>> {
- fn is_ok(arm: &Arm<'_>) -> bool {
+pub fn is_try<'tcx>(cx: &LateContext<'_>, expr: &'tcx Expr<'tcx>) -> Option<&'tcx Expr<'tcx>> {
+ fn is_ok(cx: &LateContext<'_>, arm: &Arm<'_>) -> bool {
if_chain! {
if let PatKind::TupleStruct(ref path, ref pat, None) = arm.pat.kind;
- if match_qpath(path, &paths::RESULT_OK[1..]);
+ if is_lang_ctor(cx, path, ResultOk);
if let PatKind::Binding(_, hir_id, _, None) = pat[0].kind;
if path_to_local_id(arm.body, hir_id);
then {
false
}
- fn is_err(arm: &Arm<'_>) -> bool {
+ fn is_err(cx: &LateContext<'_>, arm: &Arm<'_>) -> bool {
if let PatKind::TupleStruct(ref path, _, _) = arm.pat.kind {
- match_qpath(path, &paths::RESULT_ERR[1..])
+ is_lang_ctor(cx, path, ResultErr)
} else {
false
}
if arms.len() == 2;
if arms[0].guard.is_none();
if arms[1].guard.is_none();
- if (is_ok(&arms[0]) && is_err(&arms[1])) ||
- (is_ok(&arms[1]) && is_err(&arms[0]));
+ if (is_ok(cx, &arms[0]) && is_err(cx, &arms[1])) ||
+ (is_ok(cx, &arms[1]) && is_err(cx, &arms[0]));
then {
return Some(expr);
}
None
}
+/// Checks if the given `DefId` matches any of the paths. Returns the index of matching path, if
+/// any.
+pub fn match_any_def_paths(cx: &LateContext<'_>, did: DefId, paths: &[&[&str]]) -> Option<usize> {
+ let search_path = cx.get_def_path(did);
+ paths
+ .iter()
+ .position(|p| p.iter().map(|x| Symbol::intern(x)).eq(search_path.iter().copied()))
+}
+
+/// Checks if the given `DefId` matches the path.
pub fn match_def_path<'tcx>(cx: &LateContext<'tcx>, did: DefId, syms: &[&str]) -> bool {
- // We have to convert `syms` to `&[Symbol]` here because rustc's `match_def_path`
- // accepts only that. We should probably move to Symbols in Clippy as well.
- let syms = syms.iter().map(|p| Symbol::intern(p)).collect::<Vec<Symbol>>();
- cx.match_def_path(did, &syms)
+ // We should probably move to Symbols in Clippy as well rather than interning every time.
+ let path = cx.get_def_path(did);
+ syms.iter().map(|x| Symbol::intern(x)).eq(path.iter().copied())
}
-pub fn match_panic_call<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) -> Option<&'tcx [Expr<'tcx>]> {
- match_function_call(cx, expr, &paths::BEGIN_PANIC)
- .or_else(|| match_function_call(cx, expr, &paths::BEGIN_PANIC_FMT))
- .or_else(|| match_function_call(cx, expr, &paths::PANIC_ANY))
- .or_else(|| match_function_call(cx, expr, &paths::PANICKING_PANIC))
- .or_else(|| match_function_call(cx, expr, &paths::PANICKING_PANIC_FMT))
- .or_else(|| match_function_call(cx, expr, &paths::PANICKING_PANIC_STR))
+pub fn match_panic_call(cx: &LateContext<'_>, expr: &'tcx Expr<'_>) -> Option<&'tcx Expr<'tcx>> {
+ if let ExprKind::Call(func, [arg]) = expr.kind {
+ expr_path_res(cx, func)
+ .opt_def_id()
+ .map_or(false, |id| match_panic_def_id(cx, id))
+ .then(|| arg)
+ } else {
+ None
+ }
}
pub fn match_panic_def_id(cx: &LateContext<'_>, did: DefId) -> bool {
- match_def_path(cx, did, &paths::BEGIN_PANIC)
- || match_def_path(cx, did, &paths::BEGIN_PANIC_FMT)
- || match_def_path(cx, did, &paths::PANIC_ANY)
- || match_def_path(cx, did, &paths::PANICKING_PANIC)
- || match_def_path(cx, did, &paths::PANICKING_PANIC_FMT)
- || match_def_path(cx, did, &paths::PANICKING_PANIC_STR)
+ match_any_def_paths(
+ cx,
+ did,
+ &[
+ &paths::BEGIN_PANIC,
+ &paths::BEGIN_PANIC_FMT,
+ &paths::PANIC_ANY,
+ &paths::PANICKING_PANIC,
+ &paths::PANICKING_PANIC_FMT,
+ &paths::PANICKING_PANIC_STR,
+ ],
+ )
+ .is_some()
}
/// Returns the list of condition expressions and the list of blocks in a
(conds, blocks)
}
-/// This function returns true if the given expression is the `else` or `if else` part of an if
-/// statement
-pub fn parent_node_is_if_expr(expr: &Expr<'_>, cx: &LateContext<'_>) -> bool {
- let map = cx.tcx.hir();
- let parent_id = map.get_parent_node(expr.hir_id);
- let parent_node = map.get(parent_id);
- matches!(
- parent_node,
- Node::Expr(Expr {
- kind: ExprKind::If(_, _, _),
- ..
- })
- )
-}
-
// Finds the `#[must_use]` attribute, if any
pub fn must_use_attr(attrs: &[Attribute]) -> Option<&Attribute> {
attrs.iter().find(|a| a.has_name(sym::must_use))
did.map_or(false, |did| must_use_attr(&cx.tcx.get_attrs(did)).is_some())
}
+/// Gets the node where an expression is either used, or it's type is unified with another branch.
+pub fn get_expr_use_or_unification_node(tcx: TyCtxt<'tcx>, expr: &Expr<'_>) -> Option<Node<'tcx>> {
+ let map = tcx.hir();
+ let mut child_id = expr.hir_id;
+ let mut iter = map.parent_iter(child_id);
+ loop {
+ match iter.next() {
+ None => break None,
+ Some((id, Node::Block(_))) => child_id = id,
+ Some((id, Node::Arm(arm))) if arm.body.hir_id == child_id => child_id = id,
+ Some((_, Node::Expr(expr))) => match expr.kind {
+ ExprKind::Match(_, [arm], _) if arm.hir_id == child_id => child_id = expr.hir_id,
+ ExprKind::Block(..) | ExprKind::DropTemps(_) => child_id = expr.hir_id,
+ ExprKind::If(_, then_expr, None) if then_expr.hir_id == child_id => break None,
+ _ => break Some(Node::Expr(expr)),
+ },
+ Some((_, node)) => break Some(node),
+ }
+ }
+}
+
+/// Checks if the result of an expression is used, or it's type is unified with another branch.
+pub fn is_expr_used_or_unified(tcx: TyCtxt<'_>, expr: &Expr<'_>) -> bool {
+ !matches!(
+ get_expr_use_or_unification_node(tcx, expr),
+ None | Some(Node::Stmt(Stmt {
+ kind: StmtKind::Expr(_)
+ | StmtKind::Semi(_)
+ | StmtKind::Local(Local {
+ pat: Pat {
+ kind: PatKind::Wild,
+ ..
+ },
+ ..
+ }),
+ ..
+ }))
+ )
+}
+
+/// Checks if the expression is the final expression returned from a block.
+pub fn is_expr_final_block_expr(tcx: TyCtxt<'_>, expr: &Expr<'_>) -> bool {
+ matches!(get_parent_node(tcx, expr.hir_id), Some(Node::Block(..)))
+}
+
pub fn is_no_std_crate(cx: &LateContext<'_>) -> bool {
cx.tcx.hir().attrs(hir::CRATE_HIR_ID).iter().any(|attr| {
if let ast::AttrKind::Normal(ref attr, _) = attr.kind {
peel(pat, 0)
}
+/// Peels of expressions while the given closure returns `Some`.
+pub fn peel_hir_expr_while<'tcx>(
+ mut expr: &'tcx Expr<'tcx>,
+ mut f: impl FnMut(&'tcx Expr<'tcx>) -> Option<&'tcx Expr<'tcx>>,
+) -> &'tcx Expr<'tcx> {
+ while let Some(e) = f(expr) {
+ expr = e;
+ }
+ expr
+}
+
/// Peels off up to the given number of references on the expression. Returns the underlying
/// expression and the number of references removed.
pub fn peel_n_hir_expr_refs(expr: &'a Expr<'a>, count: usize) -> (&'a Expr<'a>, usize) {
- fn f(expr: &'a Expr<'a>, count: usize, target: usize) -> (&'a Expr<'a>, usize) {
- match expr.kind {
- ExprKind::AddrOf(_, _, expr) if count != target => f(expr, count + 1, target),
- _ => (expr, count),
- }
- }
- f(expr, 0, count)
+ let mut remaining = count;
+ let e = peel_hir_expr_while(expr, |e| match e.kind {
+ ExprKind::AddrOf(BorrowKind::Ref, _, e) if remaining != 0 => {
+ remaining -= 1;
+ Some(e)
+ },
+ _ => None,
+ });
+ (e, count - remaining)
}
/// Peels off all references on the expression. Returns the underlying expression and the number of
/// references removed.
pub fn peel_hir_expr_refs(expr: &'a Expr<'a>) -> (&'a Expr<'a>, usize) {
- fn f(expr: &'a Expr<'a>, count: usize) -> (&'a Expr<'a>, usize) {
- match expr.kind {
- ExprKind::AddrOf(BorrowKind::Ref, _, expr) => f(expr, count + 1),
- _ => (expr, count),
- }
- }
- f(expr, 0)
+ let mut count = 0;
+ let e = peel_hir_expr_while(expr, |e| match e.kind {
+ ExprKind::AddrOf(BorrowKind::Ref, _, e) => {
+ count += 1;
+ Some(e)
+ },
+ _ => None,
+ });
+ (e, count)
}
#[macro_export]
}
}
}
-
-/// Check if the resolution of a given path is an `Ok` variant of `Result`.
-pub fn is_ok_ctor(cx: &LateContext<'_>, res: Res) -> bool {
- if let Some(ok_id) = cx.tcx.lang_items().result_ok_variant() {
- if let Res::Def(DefKind::Ctor(CtorOf::Variant, CtorKind::Fn), id) = res {
- if let Some(variant_id) = cx.tcx.parent(id) {
- return variant_id == ok_id;
- }
- }
- }
- false
-}
-
-/// Check if the resolution of a given path is a `Some` variant of `Option`.
-pub fn is_some_ctor(cx: &LateContext<'_>, res: Res) -> bool {
- if let Some(some_id) = cx.tcx.lang_items().option_some_variant() {
- if let Res::Def(DefKind::Ctor(CtorOf::Variant, CtorKind::Fn), id) = res {
- if let Some(variant_id) = cx.tcx.parent(id) {
- return variant_id == some_id;
- }
- }
- }
- false
-}
projects / rust.git / blobdiff