+use clippy_utils::source::snippet_with_applicability;
+use clippy_utils::ty::match_type;
use if_chain::if_chain;
-use rustc::declare_lint_pass;
-use rustc::hir::*;
-use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
use rustc_errors::Applicability;
-use rustc_session::declare_tool_lint;
+use rustc_hir::{BinOpKind, Expr, ExprKind};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_session::{declare_lint_pass, declare_tool_lint};
use rustc_span::source_map::Spanned;
-use crate::consts::{constant, Constant};
-use crate::utils::paths;
-use crate::utils::{match_type, snippet_with_applicability, span_lint_and_sugg, walk_ptrs_ty};
+use clippy_utils::consts::{constant, Constant};
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::paths;
declare_clippy_lint! {
- /// **What it does:** Checks for calculation of subsecond microseconds or milliseconds
+ /// ### What it does
+ /// Checks for calculation of subsecond microseconds or milliseconds
/// from other `Duration` methods.
///
- /// **Why is this bad?** It's more concise to call `Duration::subsec_micros()` or
+ /// ### Why is this bad?
+ /// It's more concise to call `Duration::subsec_micros()` or
/// `Duration::subsec_millis()` than to calculate them.
///
- /// **Known problems:** None.
- ///
- /// **Example:**
+ /// ### Example
/// ```rust
/// # use std::time::Duration;
/// let dur = Duration::new(5, 0);
+ ///
+ /// // Bad
/// let _micros = dur.subsec_nanos() / 1_000;
/// let _millis = dur.subsec_nanos() / 1_000_000;
+ ///
+ /// // Good
+ /// let _micros = dur.subsec_micros();
+ /// let _millis = dur.subsec_millis();
/// ```
+ #[clippy::version = "pre 1.29.0"]
pub DURATION_SUBSEC,
complexity,
"checks for calculation of subsecond microseconds or milliseconds"
declare_lint_pass!(DurationSubsec => [DURATION_SUBSEC]);
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for DurationSubsec {
- fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr<'_>) {
+impl<'tcx> LateLintPass<'tcx> for DurationSubsec {
+ fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
if_chain! {
- if let ExprKind::Binary(Spanned { node: BinOpKind::Div, .. }, ref left, ref right) = expr.kind;
- if let ExprKind::MethodCall(ref method_path, _ , ref args) = left.kind;
- if match_type(cx, walk_ptrs_ty(cx.tables.expr_ty(&args[0])), &paths::DURATION);
- if let Some((Constant::Int(divisor), _)) = constant(cx, cx.tables, right);
+ if let ExprKind::Binary(Spanned { node: BinOpKind::Div, .. }, left, right) = expr.kind;
+ if let ExprKind::MethodCall(method_path, args, _) = left.kind;
+ if match_type(cx, cx.typeck_results().expr_ty(&args[0]).peel_refs(), &paths::DURATION);
+ if let Some((Constant::Int(divisor), _)) = constant(cx, cx.typeck_results(), right);
then {
- let suggested_fn = match (method_path.ident.as_str().as_ref(), divisor) {
+ let suggested_fn = match (method_path.ident.as_str(), divisor) {
("subsec_micros", 1_000) | ("subsec_nanos", 1_000_000) => "subsec_millis",
("subsec_nanos", 1_000) => "subsec_micros",
_ => return,
cx,
DURATION_SUBSEC,
expr.span,
- &format!("Calling `{}()` is more concise than this calculation", suggested_fn),
+ &format!("calling `{}()` is more concise than this calculation", suggested_fn),
"try",
format!(
"{}.{}()",