Rename lint into confusing_method_to_numeric_cast

Author: GuillaumeGomez

CHANGELOG.md

@@ -5594,6 +5594,7 @@ Released 2018-09-13
 [`collection_is_never_read`]: https://rust-lang.github.io/rust-clippy/master/index.html#collection_is_never_read
 [`comparison_chain`]: https://rust-lang.github.io/rust-clippy/master/index.html#comparison_chain
 [`comparison_to_empty`]: https://rust-lang.github.io/rust-clippy/master/index.html#comparison_to_empty
+[`confusing_method_to_numeric_cast`]: https://rust-lang.github.io/rust-clippy/master/index.html#confusing_method_to_numeric_cast
 [`const_is_empty`]: https://rust-lang.github.io/rust-clippy/master/index.html#const_is_empty
 [`const_static_lifetime`]: https://rust-lang.github.io/rust-clippy/master/index.html#const_static_lifetime
 [`copy_iterator`]: https://rust-lang.github.io/rust-clippy/master/index.html#copy_iterator
@@ -6068,7 +6069,6 @@ Released 2018-09-13
 [`possible_missing_comma`]: https://rust-lang.github.io/rust-clippy/master/index.html#possible_missing_comma
 [`precedence`]: https://rust-lang.github.io/rust-clippy/master/index.html#precedence
 [`precedence_bits`]: https://rust-lang.github.io/rust-clippy/master/index.html#precedence_bits
-[`primitive_method_to_numeric_cast`]: https://rust-lang.github.io/rust-clippy/master/index.html#primitive_method_to_numeric_cast
 [`print_in_format_impl`]: https://rust-lang.github.io/rust-clippy/master/index.html#print_in_format_impl
 [`print_literal`]: https://rust-lang.github.io/rust-clippy/master/index.html#print_literal
 [`print_stderr`]: https://rust-lang.github.io/rust-clippy/master/index.html#print_stderr

clippy_lints/src/casts/primitive_method_to_numeric_cast.rs renamed to clippy_lints/src/casts/confusing_method_to_numeric_cast.rs

@@ -6,7 +6,7 @@ use rustc_hir::Expr;
 use rustc_lint::LateContext;
 use rustc_middle::ty::{self, Ty};
 
-use super::PRIMITIVE_METHOD_TO_NUMERIC_CAST;
+use super::CONFUSING_METHOD_TO_NUMERIC_CAST;
 
 fn get_primitive_ty_name(ty: Ty<'_>) -> Option<&'static str> {
     match ty.kind() {
@@ -41,7 +41,7 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, cast_expr: &Expr<'_>,
 
         span_lint_and_then(
             cx,
-            PRIMITIVE_METHOD_TO_NUMERIC_CAST,
+            CONFUSING_METHOD_TO_NUMERIC_CAST,
             expr.span,
             format!("casting function pointer `{from_snippet}` to `{cast_to}`"),
             |diag| {

clippy_lints/src/casts/mod.rs

@@ -14,11 +14,11 @@ mod cast_sign_loss;
 mod cast_slice_different_sizes;
 mod cast_slice_from_raw_parts;
 mod char_lit_as_u8;
+mod confusing_method_to_numeric_cast;
 mod fn_to_numeric_cast;
 mod fn_to_numeric_cast_any;
 mod fn_to_numeric_cast_with_truncation;
 mod manual_dangling_ptr;
-mod primitive_method_to_numeric_cast;
 mod ptr_as_ptr;
 mod ptr_cast_constness;
 mod ref_as_ptr;
@@ -808,7 +808,7 @@ declare_clippy_lint! {
     /// let _ = u16::MAX as usize;
     /// ```
     #[clippy::version = "1.86.0"]
-    pub PRIMITIVE_METHOD_TO_NUMERIC_CAST,
+    pub CONFUSING_METHOD_TO_NUMERIC_CAST,
     suspicious,
     "casting a primitive method pointer to any integer type"
 }
@@ -850,7 +850,7 @@ impl_lint_pass!(Casts => [
     REF_AS_PTR,
     AS_POINTER_UNDERSCORE,
     MANUAL_DANGLING_PTR,
-    PRIMITIVE_METHOD_TO_NUMERIC_CAST,
+    CONFUSING_METHOD_TO_NUMERIC_CAST,
 ]);
 
 impl<'tcx> LateLintPass<'tcx> for Casts {
@@ -875,7 +875,7 @@ impl<'tcx> LateLintPass<'tcx> for Casts {
             ptr_cast_constness::check(cx, expr, cast_from_expr, cast_from, cast_to, self.msrv);
             as_ptr_cast_mut::check(cx, expr, cast_from_expr, cast_to);
             fn_to_numeric_cast_any::check(cx, expr, cast_from_expr, cast_from, cast_to);
-            primitive_method_to_numeric_cast::check(cx, expr, cast_from_expr, cast_from, cast_to);
+            confusing_method_to_numeric_cast::check(cx, expr, cast_from_expr, cast_from, cast_to);
             fn_to_numeric_cast::check(cx, expr, cast_from_expr, cast_from, cast_to);
             fn_to_numeric_cast_with_truncation::check(cx, expr, cast_from_expr, cast_from, cast_to);
             zero_ptr::check(cx, expr, cast_from_expr, cast_to_hir);

clippy_lints/src/declared_lints.rs

@@ -64,11 +64,11 @@ pub static LINTS: &[&crate::LintInfo] = &[
     crate::casts::CAST_SLICE_DIFFERENT_SIZES_INFO,
     crate::casts::CAST_SLICE_FROM_RAW_PARTS_INFO,
     crate::casts::CHAR_LIT_AS_U8_INFO,
+    crate::casts::CONFUSING_METHOD_TO_NUMERIC_CAST_INFO,
     crate::casts::FN_TO_NUMERIC_CAST_INFO,
     crate::casts::FN_TO_NUMERIC_CAST_ANY_INFO,
     crate::casts::FN_TO_NUMERIC_CAST_WITH_TRUNCATION_INFO,
     crate::casts::MANUAL_DANGLING_PTR_INFO,
-    crate::casts::PRIMITIVE_METHOD_TO_NUMERIC_CAST_INFO,
     crate::casts::PTR_AS_PTR_INFO,
     crate::casts::PTR_CAST_CONSTNESS_INFO,
     crate::casts::REF_AS_PTR_INFO,

clippy_utils/src/lib.rs

@@ -1836,6 +1836,12 @@ pub fn if_sequence<'tcx>(mut expr: &'tcx Expr<'tcx>) -> (Vec<&'tcx Expr<'tcx>>,
     (conds, blocks)
 }
 
+pub fn match_def_path(cx: &LateContext<'_>, did: DefId, syms: &[&str]) -> bool {
+    // 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())
+}
+
 /// Checks if the given function kind is an async function.
 pub fn is_async_fn(kind: FnKind<'_>) -> bool {
     match kind {

tests/ui/confusing_method_to_numeric_cast.fixed

@@ -0,0 +1,5 @@
+#![warn(clippy::confusing_method_to_numeric_cast)]
+
+fn main() {
+    let _ = u16::MAX as usize; //~ confusing_method_to_numeric_cast
+}

tests/ui/confusing_method_to_numeric_cast.rs

@@ -0,0 +1,5 @@
+#![warn(clippy::confusing_method_to_numeric_cast)]
+
+fn main() {
+    let _ = u16::max as usize; //~ confusing_method_to_numeric_cast
+}

tests/ui/confusing_method_to_numeric_cast.stderr

@@ -0,0 +1,16 @@
+error: casting function pointer `u16::max` to `usize`
+  --> tests/ui/confusing_method_to_numeric_cast.rs:4:13
+   |
+LL |     let _ = u16::max as usize;
+   |             ^^^^^^^^^^^^^^^^^
+   |
+   = note: `-D clippy::confusing-method-to-numeric-cast` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::confusing_method_to_numeric_cast)]`
+help: did you mean to use the associated constant?
+   |
+LL -     let _ = u16::max as usize;
+LL +     let _ = u16::MAX as usize;
+   |
+
+error: aborting due to 1 previous error
+