-use crate::utils::{get_parent_expr, span_lint, span_note_and_lint};
+use crate::utils::{get_parent_expr, span_lint, span_lint_and_note};
use if_chain::if_chain;
-use rustc::hir::intravisit::{walk_expr, NestedVisitorMap, Visitor};
-use rustc::hir::*;
-use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
+use rustc::hir::map::Map;
use rustc::ty;
-use rustc::{declare_tool_lint, lint_array};
-use syntax::ast;
+use rustc_hir::intravisit::{walk_expr, NestedVisitorMap, Visitor};
+use rustc_hir::*;
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_session::{declare_lint_pass, declare_tool_lint};
-/// **What it does:** Checks for a read and a write to the same variable where
-/// whether the read occurs before or after the write depends on the evaluation
-/// order of sub-expressions.
-///
-/// **Why is this bad?** It is often confusing to read. In addition, the
-/// sub-expression evaluation order for Rust is not well documented.
-///
-/// **Known problems:** Code which intentionally depends on the evaluation
-/// order, or which is correct for any evaluation order.
-///
-/// **Example:**
-/// ```rust
-/// let mut x = 0;
-/// let a = {
-/// x = 1;
-/// 1
-/// } + x;
-/// // Unclear whether a is 1 or 2.
-/// ```
declare_clippy_lint! {
+ /// **What it does:** Checks for a read and a write to the same variable where
+ /// whether the read occurs before or after the write depends on the evaluation
+ /// order of sub-expressions.
+ ///
+ /// **Why is this bad?** It is often confusing to read. In addition, the
+ /// sub-expression evaluation order for Rust is not well documented.
+ ///
+ /// **Known problems:** Code which intentionally depends on the evaluation
+ /// order, or which is correct for any evaluation order.
+ ///
+ /// **Example:**
+ /// ```rust
+ /// let mut x = 0;
+ /// let a = {
+ /// x = 1;
+ /// 1
+ /// } + x;
+ /// // Unclear whether a is 1 or 2.
+ /// ```
pub EVAL_ORDER_DEPENDENCE,
complexity,
"whether a variable read occurs before a write depends on sub-expression evaluation order"
}
-/// **What it does:** Checks for diverging calls that are not match arms or
-/// statements.
-///
-/// **Why is this bad?** It is often confusing to read. In addition, the
-/// sub-expression evaluation order for Rust is not well documented.
-///
-/// **Known problems:** Someone might want to use `some_bool || panic!()` as a
-/// shorthand.
-///
-/// **Example:**
-/// ```rust
-/// let a = b() || panic!() || c();
-/// // `c()` is dead, `panic!()` is only called if `b()` returns `false`
-/// let x = (a, b, c, panic!());
-/// // can simply be replaced by `panic!()`
-/// ```
declare_clippy_lint! {
+ /// **What it does:** Checks for diverging calls that are not match arms or
+ /// statements.
+ ///
+ /// **Why is this bad?** It is often confusing to read. In addition, the
+ /// sub-expression evaluation order for Rust is not well documented.
+ ///
+ /// **Known problems:** Someone might want to use `some_bool || panic!()` as a
+ /// shorthand.
+ ///
+ /// **Example:**
+ /// ```rust,no_run
+ /// # fn b() -> bool { true }
+ /// # fn c() -> bool { true }
+ /// let a = b() || panic!() || c();
+ /// // `c()` is dead, `panic!()` is only called if `b()` returns `false`
+ /// let x = (a, b, c, panic!());
+ /// // can simply be replaced by `panic!()`
+ /// ```
pub DIVERGING_SUB_EXPRESSION,
complexity,
"whether an expression contains a diverging sub expression"
}
-#[derive(Copy, Clone)]
-pub struct EvalOrderDependence;
-
-impl LintPass for EvalOrderDependence {
- fn get_lints(&self) -> LintArray {
- lint_array!(EVAL_ORDER_DEPENDENCE, DIVERGING_SUB_EXPRESSION)
- }
-
- fn name(&self) -> &'static str {
- "EvalOrderDependence"
- }
-}
+declare_lint_pass!(EvalOrderDependence => [EVAL_ORDER_DEPENDENCE, DIVERGING_SUB_EXPRESSION]);
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for EvalOrderDependence {
- fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
+ fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr<'_>) {
// Find a write to a local variable.
- match expr.node {
- ExprKind::Assign(ref lhs, _) | ExprKind::AssignOp(_, ref lhs, _) => {
- if let ExprKind::Path(ref qpath) = lhs.node {
+ match expr.kind {
+ ExprKind::Assign(ref lhs, ..) | ExprKind::AssignOp(_, ref lhs, _) => {
+ if let ExprKind::Path(ref qpath) = lhs.kind {
if let QPath::Resolved(_, ref path) = *qpath {
if path.segments.len() == 1 {
- if let def::Def::Local(var) = cx.tables.qpath_def(qpath, lhs.hir_id) {
+ if let def::Res::Local(var) = cx.tables.qpath_res(qpath, lhs.hir_id) {
let mut visitor = ReadVisitor {
cx,
var,
_ => {},
}
}
- fn check_stmt(&mut self, cx: &LateContext<'a, 'tcx>, stmt: &'tcx Stmt) {
- match stmt.node {
+ fn check_stmt(&mut self, cx: &LateContext<'a, 'tcx>, stmt: &'tcx Stmt<'_>) {
+ match stmt.kind {
StmtKind::Local(ref local) => {
if let Local { init: Some(ref e), .. } = **local {
DivergenceVisitor { cx }.visit_expr(e);
}
}
-struct DivergenceVisitor<'a, 'tcx: 'a> {
+struct DivergenceVisitor<'a, 'tcx> {
cx: &'a LateContext<'a, 'tcx>,
}
impl<'a, 'tcx> DivergenceVisitor<'a, 'tcx> {
- fn maybe_walk_expr(&mut self, e: &'tcx Expr) {
- match e.node {
- ExprKind::Closure(.., _) => {},
- ExprKind::Match(ref e, ref arms, _) => {
+ fn maybe_walk_expr(&mut self, e: &'tcx Expr<'_>) {
+ match e.kind {
+ ExprKind::Closure(..) => {},
+ ExprKind::Match(ref e, arms, _) => {
self.visit_expr(e);
for arm in arms {
if let Some(ref guard) = arm.guard {
_ => walk_expr(self, e),
}
}
- fn report_diverging_sub_expr(&mut self, e: &Expr) {
+ fn report_diverging_sub_expr(&mut self, e: &Expr<'_>) {
span_lint(self.cx, DIVERGING_SUB_EXPRESSION, e.span, "sub-expression diverges");
}
}
impl<'a, 'tcx> Visitor<'tcx> for DivergenceVisitor<'a, 'tcx> {
- fn visit_expr(&mut self, e: &'tcx Expr) {
- match e.node {
+ type Map = Map<'tcx>;
+
+ fn visit_expr(&mut self, e: &'tcx Expr<'_>) {
+ match e.kind {
ExprKind::Continue(_) | ExprKind::Break(_, _) | ExprKind::Ret(_) => self.report_diverging_sub_expr(e),
ExprKind::Call(ref func, _) => {
let typ = self.cx.tables.expr_ty(func);
- match typ.sty {
+ match typ.kind {
ty::FnDef(..) | ty::FnPtr(_) => {
let sig = typ.fn_sig(self.cx.tcx);
- if let ty::Never = self.cx.tcx.erase_late_bound_regions(&sig).output().sty {
+ if let ty::Never = self.cx.tcx.erase_late_bound_regions(&sig).output().kind {
self.report_diverging_sub_expr(e);
}
},
}
self.maybe_walk_expr(e);
}
- fn visit_block(&mut self, _: &'tcx Block) {
+ fn visit_block(&mut self, _: &'tcx Block<'_>) {
// don't continue over blocks, LateLintPass already does that
}
- fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
+ fn nested_visit_map(&mut self) -> NestedVisitorMap<'_, Self::Map> {
NestedVisitorMap::None
}
}
let map = &vis.cx.tcx.hir();
let mut cur_id = vis.write_expr.hir_id;
loop {
- let parent_id = map.get_parent_node_by_hir_id(cur_id);
+ let parent_id = map.get_parent_node(cur_id);
if parent_id == cur_id {
break;
}
- let parent_node = match map.find_by_hir_id(parent_id) {
+ let parent_node = match map.find(parent_id) {
Some(parent) => parent,
None => break,
};
Stop,
}
-fn check_expr<'a, 'tcx>(vis: &mut ReadVisitor<'a, 'tcx>, expr: &'tcx Expr) -> StopEarly {
+fn check_expr<'a, 'tcx>(vis: &mut ReadVisitor<'a, 'tcx>, expr: &'tcx Expr<'_>) -> StopEarly {
if expr.hir_id == vis.last_expr.hir_id {
return StopEarly::KeepGoing;
}
- match expr.node {
+ match expr.kind {
ExprKind::Array(_)
| ExprKind::Tup(_)
| ExprKind::MethodCall(..)
| ExprKind::Call(_, _)
- | ExprKind::Assign(_, _)
+ | ExprKind::Assign(..)
| ExprKind::Index(_, _)
| ExprKind::Repeat(_, _)
| ExprKind::Struct(_, _, _) => {
StopEarly::KeepGoing
}
-fn check_stmt<'a, 'tcx>(vis: &mut ReadVisitor<'a, 'tcx>, stmt: &'tcx Stmt) -> StopEarly {
- match stmt.node {
+fn check_stmt<'a, 'tcx>(vis: &mut ReadVisitor<'a, 'tcx>, stmt: &'tcx Stmt<'_>) -> StopEarly {
+ match stmt.kind {
StmtKind::Expr(ref expr) | StmtKind::Semi(ref expr) => check_expr(vis, expr),
// If the declaration is of a local variable, check its initializer
// expression if it has one. Otherwise, keep going.
}
/// A visitor that looks for reads from a variable.
-struct ReadVisitor<'a, 'tcx: 'a> {
+struct ReadVisitor<'a, 'tcx> {
cx: &'a LateContext<'a, 'tcx>,
- /// The id of the variable we're looking for.
- var: ast::NodeId,
+ /// The ID of the variable we're looking for.
+ var: HirId,
/// The expressions where the write to the variable occurred (for reporting
/// in the lint).
- write_expr: &'tcx Expr,
+ write_expr: &'tcx Expr<'tcx>,
/// The last (highest in the AST) expression we've checked, so we know not
/// to recheck it.
- last_expr: &'tcx Expr,
+ last_expr: &'tcx Expr<'tcx>,
}
impl<'a, 'tcx> Visitor<'tcx> for ReadVisitor<'a, 'tcx> {
- fn visit_expr(&mut self, expr: &'tcx Expr) {
+ type Map = Map<'tcx>;
+
+ fn visit_expr(&mut self, expr: &'tcx Expr<'_>) {
if expr.hir_id == self.last_expr.hir_id {
return;
}
- match expr.node {
+ match expr.kind {
ExprKind::Path(ref qpath) => {
if_chain! {
if let QPath::Resolved(None, ref path) = *qpath;
if path.segments.len() == 1;
- if let def::Def::Local(local_id) = self.cx.tables.qpath_def(qpath, expr.hir_id);
+ if let def::Res::Local(local_id) = self.cx.tables.qpath_res(qpath, expr.hir_id);
if local_id == self.var;
// Check that this is a read, not a write.
if !is_in_assignment_position(self.cx, expr);
then {
- span_note_and_lint(
+ span_lint_and_note(
self.cx,
EVAL_ORDER_DEPENDENCE,
expr.span,
// ```
//
// TODO: fix this
- ExprKind::AddrOf(_, _) => {
+ ExprKind::AddrOf(_, _, _) => {
return;
}
_ => {}
walk_expr(self, expr);
}
- fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
+ fn nested_visit_map(&mut self) -> NestedVisitorMap<'_, Self::Map> {
NestedVisitorMap::None
}
}
-/// Returns true if `expr` is the LHS of an assignment, like `expr = ...`.
-fn is_in_assignment_position(cx: &LateContext<'_, '_>, expr: &Expr) -> bool {
+/// Returns `true` if `expr` is the LHS of an assignment, like `expr = ...`.
+fn is_in_assignment_position(cx: &LateContext<'_, '_>, expr: &Expr<'_>) -> bool {
if let Some(parent) = get_parent_expr(cx, expr) {
- if let ExprKind::Assign(ref lhs, _) = parent.node {
+ if let ExprKind::Assign(ref lhs, ..) = parent.kind {
return lhs.hir_id == expr.hir_id;
}
}
projects / rust.git / blobdiff