[Clippy] Get rid of most std match_def_path usage, swap to diagnostic items.

compiler/rustc_span/src/symbol.rs

@@ -342,6 +342,7 @@ symbols! {
         Upvars,
         Vec,
         VecDeque,
+        Waker,
         Wrapper,
         Wrapping,
         Yield,
@@ -501,6 +502,7 @@ symbols! {
         black_box,
         block,
         bool,
+        bool_then,
         borrowck_graphviz_format,
         borrowck_graphviz_postflow,
         box_new,
@@ -512,6 +514,8 @@ symbols! {
         breakpoint,
         bridge,
         bswap,
+        btreemap_contains_key,
+        btreemap_insert,
         btreeset_iter,
         builtin_syntax,
         c,
@@ -680,6 +684,7 @@ symbols! {
         crt_dash_static: "crt-static",
         csky_target_feature,
         cstr_type,
+        cstring_as_c_str,
         cstring_type,
         ctlz,
         ctlz_nonzero,
@@ -835,6 +840,7 @@ symbols! {
         f16_nan,
         f16c_target_feature,
         f32,
+        f32_epsilon,
         f32_legacy_const_digits,
         f32_legacy_const_epsilon,
         f32_legacy_const_infinity,
@@ -851,6 +857,7 @@ symbols! {
         f32_legacy_const_radix,
         f32_nan,
         f64,
+        f64_epsilon,
         f64_legacy_const_digits,
         f64_legacy_const_epsilon,
         f64_legacy_const_infinity,
@@ -888,6 +895,7 @@ symbols! {
         field,
         field_init_shorthand,
         file,
+        file_options,
         float,
         float_to_int_unchecked,
         floorf128,
@@ -973,7 +981,17 @@ symbols! {
         half_open_range_patterns,
         half_open_range_patterns_in_slices,
         hash,
+        hashmap_contains_key,
+        hashmap_drain_ty,
+        hashmap_insert,
+        hashmap_iter_mut_ty,
+        hashmap_iter_ty,
+        hashmap_keys_ty,
+        hashmap_values_mut_ty,
+        hashmap_values_ty,
+        hashset_drain_ty,
         hashset_iter,
+        hashset_iter_ty,
         hexagon_target_feature,
         hidden,
         homogeneous_aggregate,
@@ -1052,6 +1070,7 @@ symbols! {
         inline_const,
         inline_const_pat,
         inout,
+        instant_now,
         instruction_set,
         integer_: "integer", // underscore to avoid clashing with the function `sym::integer` below
         integral,
@@ -1352,17 +1371,22 @@ symbols! {
         on,
         on_unimplemented,
         opaque,
+        open_options_new,
         ops,
         opt_out_copy,
         optimize,
         optimize_attribute,
         optin_builtin_traits,
         option,
         option_env,
+        option_expect,
+        option_unwrap,
         options,
         or,
         or_patterns,
         ord_cmp_method,
+        os_str_to_os_string,
+        os_string_as_os_str,
         other,
         out,
         overflow_checks,
@@ -1416,10 +1440,14 @@ symbols! {
         pat_param,
         patchable_function_entry,
         path,
+        path_main_separator,
+        path_to_pathbuf,
+        pathbuf_as_path,
         pattern_complexity,
         pattern_parentheses,
         pattern_type,
         pattern_types,
+        permissions_from_mode,
         phantom_data,
         pic,
         pie,
@@ -1571,6 +1599,7 @@ symbols! {
         residual,
         result,
         result_ffi_guarantees,
+        result_ok_method,
         resume,
         return_position_impl_trait_in_trait,
         return_type_notation,
@@ -1823,6 +1852,7 @@ symbols! {
         slice,
         slice_from_raw_parts,
         slice_from_raw_parts_mut,
+        slice_into_vec,
         slice_iter,
         slice_len_fn,
         slice_patterns,
@@ -1857,16 +1887,25 @@ symbols! {
         store,
         str,
         str_chars,
+        str_ends_with,
         str_from_utf8,
         str_from_utf8_mut,
         str_from_utf8_unchecked,
         str_from_utf8_unchecked_mut,
+        str_len,
         str_split_whitespace,
+        str_starts_with,
         str_trim,
         str_trim_end,
         str_trim_start,
         strict_provenance,
+        string_as_mut_str,
+        string_as_str,
         string_deref_patterns,
+        string_from_utf8,
+        string_insert_str,
+        string_new,
+        string_push_str,
         stringify,
         struct_field_attributes,
         struct_inherit,
@@ -2071,7 +2110,14 @@ symbols! {
         var,
         variant_count,
         vec,
+        vec_as_mut_slice,
+        vec_as_slice,
+        vec_from_elem,
+        vec_is_empty,
         vec_macro,
+        vec_new,
+        vec_pop,
+        vec_with_capacity,
         vecdeque_iter,
         version,
         vfp2,

library/alloc/src/collections/btree/map.rs

@@ -916,6 +916,7 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> {
     /// assert_eq!(map.contains_key(&2), false);
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "btreemap_contains_key")]
     pub fn contains_key<Q: ?Sized>(&self, key: &Q) -> bool
     where
         K: Borrow<Q> + Ord,
@@ -981,6 +982,7 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> {
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_confusables("push", "put", "set")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "btreemap_insert")]
     pub fn insert(&mut self, key: K, value: V) -> Option<V>
     where
         K: Ord,

library/alloc/src/ffi/c_str.rs

@@ -576,6 +576,7 @@ impl CString {
     #[inline]
     #[must_use]
     #[stable(feature = "as_c_str", since = "1.20.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "cstring_as_c_str")]
     pub fn as_c_str(&self) -> &CStr {
         &*self
     }

library/alloc/src/slice.rs

@@ -496,6 +496,7 @@ impl<T> [T] {
     #[rustc_allow_incoherent_impl]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "slice_into_vec")]
     pub fn into_vec<A: Allocator>(self: Box<Self, A>) -> Vec<T, A> {
         // N.B., see the `hack` module in this file for more details.
         hack::into_vec(self)

library/alloc/src/string.rs

@@ -440,6 +440,7 @@ impl String {
     /// ```
     #[inline]
     #[rustc_const_stable(feature = "const_string_new", since = "1.39.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "string_new")]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[must_use]
     pub const fn new() -> String {
@@ -571,6 +572,7 @@ impl String {
     /// [`into_bytes`]: String::into_bytes
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "string_from_utf8")]
     pub fn from_utf8(vec: Vec<u8>) -> Result<String, FromUtf8Error> {
         match str::from_utf8(&vec) {
             Ok(..) => Ok(String { vec }),
@@ -1073,6 +1075,7 @@ impl String {
     #[inline]
     #[must_use]
     #[stable(feature = "string_as_str", since = "1.7.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "string_as_str")]
     pub fn as_str(&self) -> &str {
         self
     }
@@ -1092,6 +1095,7 @@ impl String {
     #[inline]
     #[must_use]
     #[stable(feature = "string_as_str", since = "1.7.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "string_as_mut_str")]
     pub fn as_mut_str(&mut self) -> &mut str {
         self
     }
@@ -1111,6 +1115,7 @@ impl String {
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_confusables("append", "push")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "string_push_str")]
     pub fn push_str(&mut self, string: &str) {
         self.vec.extend_from_slice(string.as_bytes())
     }
@@ -1745,6 +1750,7 @@ impl String {
     #[cfg(not(no_global_oom_handling))]
     #[inline]
     #[stable(feature = "insert_str", since = "1.16.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "string_insert_str")]
     pub fn insert_str(&mut self, idx: usize, string: &str) {
         assert!(self.is_char_boundary(idx));
 

library/alloc/src/vec/mod.rs

@@ -416,6 +416,7 @@ impl<T> Vec<T> {
     /// ```
     #[inline]
     #[rustc_const_stable(feature = "const_vec_new", since = "1.39.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "vec_new")]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[must_use]
     pub const fn new() -> Self {
@@ -476,6 +477,7 @@ impl<T> Vec<T> {
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[must_use]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "vec_with_capacity")]
     pub fn with_capacity(capacity: usize) -> Self {
         Self::with_capacity_in(capacity, Global)
     }
@@ -1545,6 +1547,7 @@ impl<T, A: Allocator> Vec<T, A> {
     /// ```
     #[inline]
     #[stable(feature = "vec_as_slice", since = "1.7.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "vec_as_slice")]
     pub fn as_slice(&self) -> &[T] {
         self
     }
@@ -1562,6 +1565,7 @@ impl<T, A: Allocator> Vec<T, A> {
     /// ```
     #[inline]
     #[stable(feature = "vec_as_slice", since = "1.7.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "vec_as_mut_slice")]
     pub fn as_mut_slice(&mut self) -> &mut [T] {
         self
     }
@@ -2380,6 +2384,7 @@ impl<T, A: Allocator> Vec<T, A> {
     /// Takes *O*(1) time.
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "vec_pop")]
     pub fn pop(&mut self) -> Option<T> {
         if self.len == 0 {
             None
@@ -2573,6 +2578,7 @@ impl<T, A: Allocator> Vec<T, A> {
     /// assert!(!v.is_empty());
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "vec_is_empty")]
     pub fn is_empty(&self) -> bool {
         self.len() == 0
     }
@@ -3044,6 +3050,7 @@ impl<T: PartialEq, A: Allocator> Vec<T, A> {
 #[doc(hidden)]
 #[cfg(not(no_global_oom_handling))]
 #[stable(feature = "rust1", since = "1.0.0")]
+#[cfg_attr(not(test), rustc_diagnostic_item = "vec_from_elem")]
 pub fn from_elem<T: Clone>(elem: T, n: usize) -> Vec<T> {
     <T as SpecFromElem>::from_elem(elem, n, Global)
 }

library/core/src/bool.rs

@@ -55,6 +55,7 @@ impl bool {
     /// assert_eq!(a, 1);
     /// ```
     #[stable(feature = "lazy_bool_to_option", since = "1.50.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "bool_then")]
     #[inline]
     pub fn then<T, F: FnOnce() -> T>(self, f: F) -> Option<T> {
         if self { Some(f()) } else { None }

library/core/src/num/f32.rs

@@ -415,6 +415,7 @@ impl f32 {
     /// [Machine epsilon]: https://en.wikipedia.org/wiki/Machine_epsilon
     /// [`MANTISSA_DIGITS`]: f32::MANTISSA_DIGITS
     #[stable(feature = "assoc_int_consts", since = "1.43.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "f32_epsilon")]
     pub const EPSILON: f32 = 1.19209290e-07_f32;
 
     /// Smallest finite `f32` value.

library/core/src/num/f64.rs

@@ -414,6 +414,7 @@ impl f64 {
     /// [Machine epsilon]: https://en.wikipedia.org/wiki/Machine_epsilon
     /// [`MANTISSA_DIGITS`]: f64::MANTISSA_DIGITS
     #[stable(feature = "assoc_int_consts", since = "1.43.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "f64_epsilon")]
     pub const EPSILON: f64 = 2.2204460492503131e-16_f64;
 
     /// Smallest finite `f64` value.

library/core/src/option.rs

@@ -923,6 +923,7 @@ impl<T> Option<T> {
     #[inline]
     #[track_caller]
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "option_expect")]
     #[rustc_const_unstable(feature = "const_option", issue = "67441")]
     pub const fn expect(self, msg: &str) -> T {
         match self {
@@ -960,6 +961,7 @@ impl<T> Option<T> {
     #[inline(always)]
     #[track_caller]
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "option_unwrap")]
     #[rustc_const_unstable(feature = "const_option", issue = "67441")]
     pub const fn unwrap(self) -> T {
         match self {

library/core/src/result.rs

@@ -653,6 +653,7 @@ impl<T, E> Result<T, E> {
     /// ```
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "result_ok_method")]
     pub fn ok(self) -> Option<T> {
         match self {
             Ok(x) => Some(x),

library/core/src/str/mod.rs

@@ -134,6 +134,7 @@ impl str {
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_stable(feature = "const_str_len", since = "1.39.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "str_len")]
     #[must_use]
     #[inline]
     pub const fn len(&self) -> usize {
@@ -1157,6 +1158,7 @@ impl str {
     /// assert!(bananas.starts_with(&['a', 'b', 'c', 'd']));
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "str_starts_with")]
     pub fn starts_with<P: Pattern>(&self, pat: P) -> bool {
         pat.is_prefix_of(self)
     }
@@ -1181,6 +1183,7 @@ impl str {
     /// assert!(!bananas.ends_with("nana"));
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[cfg_attr(not(test), rustc_diagnostic_item = "str_ends_with")]
     pub fn ends_with<P: Pattern>(&self, pat: P) -> bool
     where
         for<'a> P::Searcher<'a>: ReverseSearcher<'a>,

library/core/src/task/wake.rs

@@ -414,6 +414,7 @@ impl<'a> ContextBuilder<'a> {
 /// [`Wake`]: ../../alloc/task/trait.Wake.html
 #[repr(transparent)]
 #[stable(feature = "futures_api", since = "1.36.0")]
+#[cfg_attr(not(test), rustc_diagnostic_item = "Waker")]
 pub struct Waker {
     waker: RawWaker,
 }