OpenE2K/rust
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

duration_subsec: Add check for subsec_micros

Browse Source
This commit is contained in:
Michael Wright 2018-06-12 08:25:10 +02:00
parent 2d427ea7ee
commit 725e9621d0
3 changed files with 33 additions and 27 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
clippy_lints/src/duration_subsec.rs
View File

@ -6,11 +6,11 @@ use crate::consts::{constant, Constant};
use crate::utils::paths;
use crate::utils::{match_type, snippet, span_lint_and_sugg, walk_ptrs_ty};
/// **What it does:** Checks for calculation of subsecond microseconds or milliseconds from
/// `Duration::subsec_nanos()`.
/// **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
/// `Duration::subsec_millis()`.
/// `Duration::subsec_millis()` than to calculate them.
///
/// **Known problems:** None.
///
@ -23,7 +23,7 @@ use crate::utils::{match_type, snippet, span_lint_and_sugg, walk_ptrs_ty};
declare_clippy_lint! {
pub DURATION_SUBSEC,
complexity,
"checks for `dur.subsec_nanos() / 1_000` or `dur.subsec_nanos() / 1_000_000`"
"checks for calculation of subsecond microseconds or milliseconds"
}
#[derive(Copy, Clone)]
@ -40,16 +40,15 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for DurationSubsec {
if_chain! {
if let ExprBinary(Spanned { node: BiDiv, .. }, ref left, ref right) = expr.node;
if let ExprMethodCall(ref method_path, _ , ref args) = left.node;
if method_path.name == "subsec_nanos";
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);
then {
let suggested_fn = match divisor {
1_000 => "subsec_micros",
1_000_000 => "subsec_millis",
let suggested_fn = match (method_path.name.as_str().as_ref(), divisor) {
("subsec_micros", 1_000) => "subsec_millis",
("subsec_nanos", 1_000) => "subsec_micros",
("subsec_nanos", 1_000_000) => "subsec_millis",
_ => return,
};
span_lint_and_sugg(
cx,
DURATION_SUBSEC,

11
tests/ui/duration_subsec.rs
View File

@ -5,14 +5,16 @@ use std::time::Duration;
fn main() {
let dur = Duration::new(5, 0);
let bad_millis_1 = dur.subsec_micros() / 1_000;
let bad_millis_2 = dur.subsec_nanos() / 1_000_000;
let good_millis = dur.subsec_millis();
assert_eq!(bad_millis_1, good_millis);
assert_eq!(bad_millis_2, good_millis);
let bad_micros = dur.subsec_nanos() / 1_000;
let good_micros = dur.subsec_micros();
assert_eq!(bad_micros, good_micros);
let bad_millis = dur.subsec_nanos() / 1_000_000;
let good_millis = dur.subsec_millis();
assert_eq!(bad_millis, good_millis);
// Handle refs
let _ = (&dur).subsec_nanos() / 1_000;
@ -22,5 +24,4 @@ fn main() {
// Other literals aren't linted
let _ = dur.subsec_nanos() / 699;
}

32
tests/ui/duration_subsec.stderr
View File

@ -1,28 +1,34 @@
error: Calling `subsec_micros()` is more concise than this calculation
--> $DIR/duration_subsec.rs:8:22
error: Calling `subsec_millis()` is more concise than this calculation
--> $DIR/duration_subsec.rs:8:24
|
8 | let bad_micros = dur.subsec_nanos() / 1_000;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `dur.subsec_micros()`
8 | let bad_millis_1 = dur.subsec_micros() / 1_000;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `dur.subsec_millis()`
|
= note: `-D duration-subsec` implied by `-D warnings`
error: Calling `subsec_millis()` is more concise than this calculation
--> $DIR/duration_subsec.rs:12:22
|
12 | let bad_millis = dur.subsec_nanos() / 1_000_000;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `dur.subsec_millis()`
--> $DIR/duration_subsec.rs:9:24
|
9 | let bad_millis_2 = dur.subsec_nanos() / 1_000_000;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `dur.subsec_millis()`
error: Calling `subsec_micros()` is more concise than this calculation
--> $DIR/duration_subsec.rs:17:13
--> $DIR/duration_subsec.rs:14:22
|
17 | let _ = (&dur).subsec_nanos() / 1_000;
14 | let bad_micros = dur.subsec_nanos() / 1_000;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `dur.subsec_micros()`
error: Calling `subsec_micros()` is more concise than this calculation
--> $DIR/duration_subsec.rs:19:13
|
19 | let _ = (&dur).subsec_nanos() / 1_000;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `(&dur).subsec_micros()`
error: Calling `subsec_micros()` is more concise than this calculation
--> $DIR/duration_subsec.rs:21:13
--> $DIR/duration_subsec.rs:23:13
|
21 | let _ = dur.subsec_nanos() / NANOS_IN_MICRO;
23 | let _ = dur.subsec_nanos() / NANOS_IN_MICRO;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `dur.subsec_micros()`
error: aborting due to 4 previous errors
error: aborting due to 5 previous errors