Rename [misleading_use_of_ok] to [unused_result_ok] and add macro tests

Author: ithinuel

CHANGELOG.md

@@ -5347,7 +5347,6 @@ Released 2018-09-13
 [`min_ident_chars`]: https://rust-lang.github.io/rust-clippy/master/index.html#min_ident_chars
 [`min_max`]: https://rust-lang.github.io/rust-clippy/master/index.html#min_max
 [`misaligned_transmute`]: https://rust-lang.github.io/rust-clippy/master/index.html#misaligned_transmute
-[`misleading_use_of_ok`]: https://rust-lang.github.io/rust-clippy/master/index.html#misleading_use_of_ok
 [`mismatched_target_os`]: https://rust-lang.github.io/rust-clippy/master/index.html#mismatched_target_os
 [`mismatching_type_param_order`]: https://rust-lang.github.io/rust-clippy/master/index.html#mismatching_type_param_order
 [`misnamed_getters`]: https://rust-lang.github.io/rust-clippy/master/index.html#misnamed_getters
@@ -5704,6 +5703,7 @@ Released 2018-09-13
 [`unused_io_amount`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_io_amount
 [`unused_label`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_label
 [`unused_peekable`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_peekable
+[`unused_result_ok`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_result_ok
 [`unused_rounding`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_rounding
 [`unused_self`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_self
 [`unused_unit`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_unit

clippy_lints/src/declared_lints.rs

@@ -477,7 +477,6 @@ pub(crate) static LINTS: &[&crate::LintInfo] = &[
     crate::misc_early::UNNEEDED_WILDCARD_PATTERN_INFO,
     crate::misc_early::UNSEPARATED_LITERAL_SUFFIX_INFO,
     crate::misc_early::ZERO_PREFIXED_LITERAL_INFO,
-    crate::misleading_use_of_ok::MISLEADING_USE_OF_OK_INFO,
     crate::mismatching_type_param_order::MISMATCHING_TYPE_PARAM_ORDER_INFO,
     crate::missing_assert_message::MISSING_ASSERT_MESSAGE_INFO,
     crate::missing_asserts_for_indexing::MISSING_ASSERTS_FOR_INDEXING_INFO,
@@ -711,6 +710,7 @@ pub(crate) static LINTS: &[&crate::LintInfo] = &[
     crate::unused_async::UNUSED_ASYNC_INFO,
     crate::unused_io_amount::UNUSED_IO_AMOUNT_INFO,
     crate::unused_peekable::UNUSED_PEEKABLE_INFO,
+    crate::unused_result_ok::UNUSED_RESULT_OK_INFO,
     crate::unused_rounding::UNUSED_ROUNDING_INFO,
     crate::unused_self::UNUSED_SELF_INFO,
     crate::unused_unit::UNUSED_UNIT_INFO,

clippy_lints/src/lib.rs

@@ -212,7 +212,6 @@ mod min_ident_chars;
 mod minmax;
 mod misc;
 mod misc_early;
-mod misleading_use_of_ok;
 mod mismatching_type_param_order;
 mod missing_assert_message;
 mod missing_asserts_for_indexing;
@@ -350,6 +349,7 @@ mod unsafe_removed_from_name;
 mod unused_async;
 mod unused_io_amount;
 mod unused_peekable;
+mod unused_result_ok;
 mod unused_rounding;
 mod unused_self;
 mod unused_unit;
@@ -766,7 +766,7 @@ pub fn register_lints(store: &mut rustc_lint::LintStore, conf: &'static Conf) {
     store.register_late_pass(move |_| Box::new(missing_doc::MissingDoc::new(missing_docs_in_crate_items)));
     store.register_late_pass(|_| Box::new(missing_inline::MissingInline));
     store.register_late_pass(move |_| Box::new(exhaustive_items::ExhaustiveItems));
-    store.register_late_pass(|_| Box::new(misleading_use_of_ok::MisleadingUseOfOk));
+    store.register_late_pass(|_| Box::new(unused_result_ok::UnusedResultOk));
     store.register_late_pass(|_| Box::new(match_result_ok::MatchResultOk));
     store.register_late_pass(|_| Box::new(partialeq_ne_impl::PartialEqNeImpl));
     store.register_late_pass(|_| Box::new(unused_io_amount::UnusedIoAmount));

clippy_lints/src/misleading_use_of_ok.rs clippy_lints/src/unused_result_ok.rs

@@ -27,13 +27,13 @@ declare_clippy_lint! {
     /// let _ = some_function();
     /// ```
     #[clippy::version = "1.70.0"]
-    pub MISLEADING_USE_OF_OK,
+    pub UNUSED_RESULT_OK,
     style,
     "Use of `.ok()` to silence `Result`'s `#[must_use]` is misleading. Use `let _ =` instead."
 }
-declare_lint_pass!(MisleadingUseOfOk => [MISLEADING_USE_OF_OK]);
+declare_lint_pass!(UnusedResultOk => [UNUSED_RESULT_OK]);
 
-impl LateLintPass<'_> for MisleadingUseOfOk {
+impl LateLintPass<'_> for UnusedResultOk {
     fn check_stmt(&mut self, cx: &LateContext<'_>, stmt: &Stmt<'_>) {
         if let StmtKind::Semi(expr) = stmt.kind &&
             let ExprKind::MethodCall(ok_path, recv, [], ..) = expr.kind //check is expr.ok() has type Result<T,E>.ok(, _)
@@ -47,7 +47,7 @@ impl LateLintPass<'_> for MisleadingUseOfOk {
             let sugg = format!("let _ = {snippet}");
             span_lint_and_sugg(
                 cx,
-                MISLEADING_USE_OF_OK,
+                UNUSED_RESULT_OK,
                 expr.span,
                 "ignoring a result with `.ok()` is misleading",
                 "consider using `let _ =` and removing the call to `.ok()` instead",

tests/ui/misleading_use_of_ok.fixed

@@ -0,0 +1,51 @@
+//@aux-build:proc_macros.rs
+#![warn(clippy::unused_result_ok)]
+#![allow(dead_code)]
+
+#[macro_use]
+extern crate proc_macros;
+
+fn bad_style(x: &str) {
+    let _ = x.parse::<u32>();
+}
+
+fn good_style(x: &str) -> Option<u32> {
+    x.parse::<u32>().ok()
+}
+
+#[rustfmt::skip]
+fn strange_parse(x: &str) {
+    let _ = x   .   parse::<i32>();
+}
+
+macro_rules! v {
+    () => {
+        Ok::<(), ()>(())
+    };
+}
+
+macro_rules! w {
+    () => {
+        let _ = Ok::<(), ()>(());
+    };
+}
+
+fn main() {
+    let _ = v!();
+    w!();
+
+    external! {
+        macro_rules! x {
+            () => { Ok::<(), ()>(()) }
+        }
+        macro_rules! y {
+            () => { Ok::<(), ()>(()).ok(); }
+        }
+
+        x!().ok();
+        y!();
+    };
+
+    let _ = x!();
+    y!();
+}

tests/ui/misleading_use_of_ok.rs

@@ -0,0 +1,51 @@
+//@aux-build:proc_macros.rs
+#![warn(clippy::unused_result_ok)]
+#![allow(dead_code)]
+
+#[macro_use]
+extern crate proc_macros;
+
+fn bad_style(x: &str) {
+    x.parse::<u32>().ok();
+}
+
+fn good_style(x: &str) -> Option<u32> {
+    x.parse::<u32>().ok()
+}
+
+#[rustfmt::skip]
+fn strange_parse(x: &str) {
+    x   .   parse::<i32>()   .   ok   ();
+}
+
+macro_rules! v {
+    () => {
+        Ok::<(), ()>(())
+    };
+}
+
+macro_rules! w {
+    () => {
+        Ok::<(), ()>(()).ok();
+    };
+}
+
+fn main() {
+    v!().ok();
+    w!();
+
+    external! {
+        macro_rules! x {
+            () => { Ok::<(), ()>(()) }
+        }
+        macro_rules! y {
+            () => { Ok::<(), ()>(()).ok(); }
+        }
+
+        x!().ok();
+        y!();
+    };
+
+    x!().ok();
+    y!();
+}

tests/ui/misleading_use_of_ok.stderr

@@ -0,0 +1,63 @@
+error: ignoring a result with `.ok()` is misleading
+  --> $DIR/unused_result_ok.rs:9:5
+   |
+LL |     x.parse::<u32>().ok();
+   |     ^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: `-D clippy::unused-result-ok` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::unused_result_ok)]`
+help: consider using `let _ =` and removing the call to `.ok()` instead
+   |
+LL |     let _ = x.parse::<u32>();
+   |     ~~~~~~~~~~~~~~~~~~~~~~~~
+
+error: ignoring a result with `.ok()` is misleading
+  --> $DIR/unused_result_ok.rs:18:5
+   |
+LL |     x   .   parse::<i32>()   .   ok   ();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: consider using `let _ =` and removing the call to `.ok()` instead
+   |
+LL |     let _ = x   .   parse::<i32>();
+   |     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+error: ignoring a result with `.ok()` is misleading
+  --> $DIR/unused_result_ok.rs:34:5
+   |
+LL |     v!().ok();
+   |     ^^^^^^^^^
+   |
+help: consider using `let _ =` and removing the call to `.ok()` instead
+   |
+LL |     let _ = v!();
+   |     ~~~~~~~~~~~~
+
+error: ignoring a result with `.ok()` is misleading
+  --> $DIR/unused_result_ok.rs:29:9
+   |
+LL |         Ok::<(), ()>(()).ok();
+   |         ^^^^^^^^^^^^^^^^^^^^^
+...
+LL |     w!();
+   |     ---- in this macro invocation
+   |
+   = note: this error originates in the macro `w` (in Nightly builds, run with -Z macro-backtrace for more info)
+help: consider using `let _ =` and removing the call to `.ok()` instead
+   |
+LL |         let _ = Ok::<(), ()>(());
+   |         ~~~~~~~~~~~~~~~~~~~~~~~~
+
+error: ignoring a result with `.ok()` is misleading
+  --> $DIR/unused_result_ok.rs:49:5
+   |
+LL |     x!().ok();
+   |     ^^^^^^^^^
+   |
+help: consider using `let _ =` and removing the call to `.ok()` instead
+   |
+LL |     let _ = x!();
+   |     ~~~~~~~~~~~~
+
+error: aborting due to 5 previous errors
+