Update Clippy

Author: JohnTitor

clippy_lints/src/consts.rs

@@ -490,9 +490,12 @@ pub fn miri_to_const(result: &ty::Const<'_>) -> Option<Constant> {
         },
         ConstValue::Slice { data, start, end } => match result.ty.sty {
             ty::Ref(_, tam, _) => match tam.sty {
-                ty::Str => String::from_utf8(data.bytes[start..end].to_owned())
-                    .ok()
-                    .map(Constant::Str),
+                ty::Str => String::from_utf8(
+                    data.inspect_with_undef_and_ptr_outside_interpreter(start..end)
+                        .to_owned(),
+                )
+                .ok()
+                .map(Constant::Str),
                 _ => None,
             },
             _ => None,

clippy_lints/src/lifetimes.rs

@@ -9,7 +9,7 @@ use syntax::source_map::Span;
 use syntax::symbol::kw;
 
 use crate::reexport::*;
-use crate::utils::{last_path_segment, span_lint};
+use crate::utils::{last_path_segment, span_lint, trait_ref_of_method};
 
 declare_clippy_lint! {
     /// **What it does:** Checks for lifetime annotations which can be removed by
@@ -60,13 +60,21 @@ declare_lint_pass!(Lifetimes => [NEEDLESS_LIFETIMES, EXTRA_UNUSED_LIFETIMES]);
 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Lifetimes {
     fn check_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx Item) {
         if let ItemKind::Fn(ref decl, _, ref generics, id) = item.node {
-            check_fn_inner(cx, decl, Some(id), generics, item.span);
+            check_fn_inner(cx, decl, Some(id), generics, item.span, true);
         }
     }
 
     fn check_impl_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx ImplItem) {
         if let ImplItemKind::Method(ref sig, id) = item.node {
-            check_fn_inner(cx, &sig.decl, Some(id), &item.generics, item.span);
+            let report_extra_lifetimes = trait_ref_of_method(cx, item.hir_id).is_none();
+            check_fn_inner(
+                cx,
+                &sig.decl,
+                Some(id),
+                &item.generics,
+                item.span,
+                report_extra_lifetimes,
+            );
         }
     }
 
@@ -76,7 +84,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Lifetimes {
                 TraitMethod::Required(_) => None,
                 TraitMethod::Provided(id) => Some(id),
             };
-            check_fn_inner(cx, &sig.decl, body, &item.generics, item.span);
+            check_fn_inner(cx, &sig.decl, body, &item.generics, item.span, true);
         }
     }
 }
@@ -95,6 +103,7 @@ fn check_fn_inner<'a, 'tcx>(
     body: Option<BodyId>,
     generics: &'tcx Generics,
     span: Span,
+    report_extra_lifetimes: bool,
 ) {
     if in_external_macro(cx.sess(), span) || has_where_lifetimes(cx, &generics.where_clause) {
         return;
@@ -144,7 +153,9 @@ fn check_fn_inner<'a, 'tcx>(
              (or replaced with `'_` if needed by type declaration)",
         );
     }
-    report_extra_lifetimes(cx, decl, generics);
+    if report_extra_lifetimes {
+        self::report_extra_lifetimes(cx, decl, generics);
+    }
 }
 
 fn could_use_elision<'a, 'tcx>(

clippy_lints/src/loops.rs

@@ -298,26 +298,25 @@ declare_clippy_lint! {
     /// **What it does:** Checks `for` loops over slices with an explicit counter
     /// and suggests the use of `.enumerate()`.
     ///
-    /// **Why is it bad?** Not only is the version using `.enumerate()` more
-    /// readable, the compiler is able to remove bounds checks which can lead to
-    /// faster code in some instances.
+    /// **Why is it bad?** Using `.enumerate()` makes the intent more clear,
+    /// declutters the code and may be faster in some instances.
     ///
     /// **Known problems:** None.
     ///
     /// **Example:**
     /// ```rust
     /// # let v = vec![1];
-    /// # fn foo(bar: usize) {}
     /// # fn bar(bar: usize, baz: usize) {}
-    /// for i in 0..v.len() { foo(v[i]); }
-    /// for i in 0..v.len() { bar(i, v[i]); }
+    /// let mut i = 0;
+    /// for item in &v {
+    ///     bar(i, *item);
+    ///     i += 1;
+    /// }
     /// ```
     /// Could be written as
     /// ```rust
     /// # let v = vec![1];
-    /// # fn foo(bar: usize) {}
     /// # fn bar(bar: usize, baz: usize) {}
-    /// for item in &v { foo(*item); }
     /// for (i, item) in v.iter().enumerate() { bar(i, *item); }
     /// ```
     pub EXPLICIT_COUNTER_LOOP,

clippy_lints/src/misc_early.rs

@@ -393,7 +393,8 @@ impl MiscEarlyLints {
         // The `line!()` macro is compiler built-in and a special case for these lints.
         let lit_snip = match snippet_opt(cx, lit.span) {
             Some(snip) => {
-                if snip.contains('!') {
+                // The snip could be empty in case of expand from procedure macro
+                if snip.is_empty() || snip.contains('!') {
                     return;
                 }
                 snip

clippy_lints/src/utils/mod.rs

@@ -88,6 +88,10 @@ pub fn in_constant(cx: &LateContext<'_, '_>, id: HirId) -> bool {
             node: ItemKind::Fn(_, header, ..),
             ..
         }) => header.constness == Constness::Const,
+        Node::ImplItem(&ImplItem {
+            node: ImplItemKind::Method(ref sig, _),
+            ..
+        }) => sig.header.constness == Constness::Const,
         _ => false,
     }
 }

tests/ui/cast_lossless_float.fixed

@@ -32,3 +32,14 @@ fn main() {
 const fn abc(input: f32) -> f64 {
     input as f64
 }
+
+// Same as the above issue. We can't suggest `::from` in const fns in impls
+mod cast_lossless_in_impl {
+    struct A;
+
+    impl A {
+        pub const fn convert(x: f32) -> f64 {
+            x as f64
+        }
+    }
+}

tests/ui/cast_lossless_float.rs

@@ -32,3 +32,14 @@ fn main() {
 const fn abc(input: f32) -> f64 {
     input as f64
 }
+
+// Same as the above issue. We can't suggest `::from` in const fns in impls
+mod cast_lossless_in_impl {
+    struct A;
+
+    impl A {
+        pub const fn convert(x: f32) -> f64 {
+            x as f64
+        }
+    }
+}

tests/ui/cast_lossless_integer.fixed

@@ -34,3 +34,14 @@ fn main() {
 const fn abc(input: u16) -> u32 {
     input as u32
 }
+
+// Same as the above issue. We can't suggest `::from` in const fns in impls
+mod cast_lossless_in_impl {
+    struct A;
+
+    impl A {
+        pub const fn convert(x: u32) -> u64 {
+            x as u64
+        }
+    }
+}

tests/ui/cast_lossless_integer.rs

@@ -34,3 +34,14 @@ fn main() {
 const fn abc(input: u16) -> u32 {
     input as u32
 }
+
+// Same as the above issue. We can't suggest `::from` in const fns in impls
+mod cast_lossless_in_impl {
+    struct A;
+
+    impl A {
+        pub const fn convert(x: u32) -> u64 {
+            x as u64
+        }
+    }
+}

tests/ui/extra_unused_lifetimes.rs

@@ -61,4 +61,15 @@ impl X {
     fn explicit_self_with_lifetime<'a>(self: &'a Self) {}
 }
 
+// Methods implementing traits must have matching lifetimes
+mod issue4291 {
+    trait BadTrait {
+        fn unused_lt<'a>(x: u8) {}
+    }
+
+    impl BadTrait for () {
+        fn unused_lt<'a>(_x: u8) {}
+    }
+}
+
 fn main() {}