Auto merge of rust-lang#108474 - Jarcho:clippyup, r=Manishearth

Update Clippy

Seems like `@flip1995` so this is a couple days late.

r? `@Manishearth`

Author: bors

Diff for: src/tools/clippy/CHANGELOG.md

@@ -4430,6 +4430,7 @@ Released 2018-09-13
 [`if_same_then_else`]: https://rust-lang.github.io/rust-clippy/master/index.html#if_same_then_else
 [`if_then_some_else_none`]: https://rust-lang.github.io/rust-clippy/master/index.html#if_then_some_else_none
 [`ifs_same_cond`]: https://rust-lang.github.io/rust-clippy/master/index.html#ifs_same_cond
+[`impl_trait_in_params`]: https://rust-lang.github.io/rust-clippy/master/index.html#impl_trait_in_params
 [`implicit_clone`]: https://rust-lang.github.io/rust-clippy/master/index.html#implicit_clone
 [`implicit_hasher`]: https://rust-lang.github.io/rust-clippy/master/index.html#implicit_hasher
 [`implicit_return`]: https://rust-lang.github.io/rust-clippy/master/index.html#implicit_return
@@ -4494,6 +4495,7 @@ Released 2018-09-13
 [`let_underscore_future`]: https://rust-lang.github.io/rust-clippy/master/index.html#let_underscore_future
 [`let_underscore_lock`]: https://rust-lang.github.io/rust-clippy/master/index.html#let_underscore_lock
 [`let_underscore_must_use`]: https://rust-lang.github.io/rust-clippy/master/index.html#let_underscore_must_use
+[`let_underscore_untyped`]: https://rust-lang.github.io/rust-clippy/master/index.html#let_underscore_untyped
 [`let_unit_value`]: https://rust-lang.github.io/rust-clippy/master/index.html#let_unit_value
 [`linkedlist`]: https://rust-lang.github.io/rust-clippy/master/index.html#linkedlist
 [`logic_bug`]: https://rust-lang.github.io/rust-clippy/master/index.html#logic_bug
@@ -4620,6 +4622,7 @@ Released 2018-09-13
 [`no_effect`]: https://rust-lang.github.io/rust-clippy/master/index.html#no_effect
 [`no_effect_replace`]: https://rust-lang.github.io/rust-clippy/master/index.html#no_effect_replace
 [`no_effect_underscore_binding`]: https://rust-lang.github.io/rust-clippy/master/index.html#no_effect_underscore_binding
+[`no_mangle_with_rust_abi`]: https://rust-lang.github.io/rust-clippy/master/index.html#no_mangle_with_rust_abi
 [`non_ascii_literal`]: https://rust-lang.github.io/rust-clippy/master/index.html#non_ascii_literal
 [`non_octal_unix_permissions`]: https://rust-lang.github.io/rust-clippy/master/index.html#non_octal_unix_permissions
 [`non_send_fields_in_send_ty`]: https://rust-lang.github.io/rust-clippy/master/index.html#non_send_fields_in_send_ty
@@ -4675,6 +4678,7 @@ Released 2018-09-13
 [`pub_enum_variant_names`]: https://rust-lang.github.io/rust-clippy/master/index.html#pub_enum_variant_names
 [`pub_use`]: https://rust-lang.github.io/rust-clippy/master/index.html#pub_use
 [`question_mark`]: https://rust-lang.github.io/rust-clippy/master/index.html#question_mark
+[`question_mark_used`]: https://rust-lang.github.io/rust-clippy/master/index.html#question_mark_used
 [`range_minus_one`]: https://rust-lang.github.io/rust-clippy/master/index.html#range_minus_one
 [`range_plus_one`]: https://rust-lang.github.io/rust-clippy/master/index.html#range_plus_one
 [`range_step_by_zero`]: https://rust-lang.github.io/rust-clippy/master/index.html#range_step_by_zero
@@ -4734,6 +4738,7 @@ Released 2018-09-13
 [`should_assert_eq`]: https://rust-lang.github.io/rust-clippy/master/index.html#should_assert_eq
 [`should_implement_trait`]: https://rust-lang.github.io/rust-clippy/master/index.html#should_implement_trait
 [`significant_drop_in_scrutinee`]: https://rust-lang.github.io/rust-clippy/master/index.html#significant_drop_in_scrutinee
+[`significant_drop_tightening`]: https://rust-lang.github.io/rust-clippy/master/index.html#significant_drop_tightening
 [`similar_names`]: https://rust-lang.github.io/rust-clippy/master/index.html#similar_names
 [`single_char_add_str`]: https://rust-lang.github.io/rust-clippy/master/index.html#single_char_add_str
 [`single_char_lifetime_names`]: https://rust-lang.github.io/rust-clippy/master/index.html#single_char_lifetime_names
@@ -4764,6 +4769,7 @@ Released 2018-09-13
 [`suboptimal_flops`]: https://rust-lang.github.io/rust-clippy/master/index.html#suboptimal_flops
 [`suspicious_arithmetic_impl`]: https://rust-lang.github.io/rust-clippy/master/index.html#suspicious_arithmetic_impl
 [`suspicious_assignment_formatting`]: https://rust-lang.github.io/rust-clippy/master/index.html#suspicious_assignment_formatting
+[`suspicious_command_arg_space`]: https://rust-lang.github.io/rust-clippy/master/index.html#suspicious_command_arg_space
 [`suspicious_else_formatting`]: https://rust-lang.github.io/rust-clippy/master/index.html#suspicious_else_formatting
 [`suspicious_map`]: https://rust-lang.github.io/rust-clippy/master/index.html#suspicious_map
 [`suspicious_op_assign_impl`]: https://rust-lang.github.io/rust-clippy/master/index.html#suspicious_op_assign_impl
@@ -4790,6 +4796,7 @@ Released 2018-09-13
 [`transmute_int_to_bool`]: https://rust-lang.github.io/rust-clippy/master/index.html#transmute_int_to_bool
 [`transmute_int_to_char`]: https://rust-lang.github.io/rust-clippy/master/index.html#transmute_int_to_char
 [`transmute_int_to_float`]: https://rust-lang.github.io/rust-clippy/master/index.html#transmute_int_to_float
+[`transmute_int_to_non_zero`]: https://rust-lang.github.io/rust-clippy/master/index.html#transmute_int_to_non_zero
 [`transmute_null_to_fn`]: https://rust-lang.github.io/rust-clippy/master/index.html#transmute_null_to_fn
 [`transmute_num_to_bytes`]: https://rust-lang.github.io/rust-clippy/master/index.html#transmute_num_to_bytes
 [`transmute_ptr_to_ptr`]: https://rust-lang.github.io/rust-clippy/master/index.html#transmute_ptr_to_ptr

Diff for: src/tools/clippy/README.md

@@ -19,21 +19,35 @@ You can choose how much Clippy is supposed to ~~annoy~~ help you by changing the
 | `clippy::complexity`  | code that does something simple but in a complex way                                | **warn**      |
 | `clippy::perf`        | code that can be written to run faster                                              | **warn**      |
 | `clippy::pedantic`    | lints which are rather strict or have occasional false positives                    | allow         |
+| `clippy::restriction` | lints which prevent the use of language and library features[^restrict]             | allow         |
 | `clippy::nursery`     | new lints that are still under development                                          | allow         |
 | `clippy::cargo`       | lints for the cargo manifest                                                        | allow         |
 
 More to come, please [file an issue](https://github.com/rust-lang/rust-clippy/issues) if you have ideas!
 
-The [lint list](https://rust-lang.github.io/rust-clippy/master/index.html) also contains "restriction lints", which are
-for things which are usually not considered "bad", but may be useful to turn on in specific cases. These should be used
-very selectively, if at all.
+The `restriction` category should, *emphatically*, not be enabled as a whole. The contained
+lints may lint against perfectly reasonable code, may not have an alternative suggestion,
+and may contradict any other lints (including other categories). Lints should be considered
+on a case-by-case basis before enabling.
+
+[^restrict]: Some use cases for `restriction` lints include:
+    - Strict coding styles (e.g. [`clippy::else_if_without_else`]).
+    - Additional restrictions on CI (e.g. [`clippy::todo`]).
+    - Preventing panicking in certain functions (e.g. [`clippy::unwrap_used`]).
+    - Running a lint only on a subset of code (e.g. `#[forbid(clippy::float_arithmetic)]` on a module).
+
+[`clippy::else_if_without_else`]: https://rust-lang.github.io/rust-clippy/master/index.html#else_if_without_else
+[`clippy::todo`]: https://rust-lang.github.io/rust-clippy/master/index.html#todo
+[`clippy::unwrap_used`]: https://rust-lang.github.io/rust-clippy/master/index.html#unwrap_used
+
+---
 
 Table of contents:
 
-*   [Usage instructions](#usage)
-*   [Configuration](#configuration)
-*   [Contributing](#contributing)
-*   [License](#license)
+* [Usage instructions](#usage)
+* [Configuration](#configuration)
+* [Contributing](#contributing)
+* [License](#license)
 
 ## Usage
 
@@ -64,6 +78,7 @@ Once you have rustup and the latest stable release (at least Rust 1.29) installe
 ```terminal
 rustup component add clippy
 ```
+
 If it says that it can't find the `clippy` component, please run `rustup self update`.
 
 #### Step 3: Run Clippy
@@ -143,16 +158,16 @@ line. (You can swap `clippy::all` with the specific lint category you are target
 
 You can add options to your code to `allow`/`warn`/`deny` Clippy lints:
 
-*   the whole set of `Warn` lints using the `clippy` lint group (`#![deny(clippy::all)]`).
+* the whole set of `Warn` lints using the `clippy` lint group (`#![deny(clippy::all)]`).
     Note that `rustc` has additional [lint groups](https://doc.rust-lang.org/rustc/lints/groups.html).
 
-*   all lints using both the `clippy` and `clippy::pedantic` lint groups (`#![deny(clippy::all)]`,
+* all lints using both the `clippy` and `clippy::pedantic` lint groups (`#![deny(clippy::all)]`,
     `#![deny(clippy::pedantic)]`). Note that `clippy::pedantic` contains some very aggressive
     lints prone to false positives.
 
-*   only some lints (`#![deny(clippy::single_match, clippy::box_vec)]`, etc.)
+* only some lints (`#![deny(clippy::single_match, clippy::box_vec)]`, etc.)
 
-*   `allow`/`warn`/`deny` can be limited to a single function or module using `#[allow(...)]`, etc.
+* `allow`/`warn`/`deny` can be limited to a single function or module using `#[allow(...)]`, etc.
 
 Note: `allow` means to suppress the lint for your code. With `warn` the lint
 will only emit a warning, while with `deny` the lint will emit an error, when
@@ -176,12 +191,14 @@ cargo clippy -- -W clippy::lint_name
 
 This also works with lint groups. For example, you
 can run Clippy with warnings for all lints enabled:
+
 ```terminal
 cargo clippy -- -W clippy::pedantic
 ```
 
 If you care only about a single lint, you can allow all others and then explicitly warn on
 the lint(s) you are interested in:
+
 ```terminal
 cargo clippy -- -A clippy::all -W clippy::useless_format -W clippy::...
 ```

Diff for: src/tools/clippy/book/src/development/infrastructure/backport.md

@@ -28,6 +28,7 @@ repository. You can do this with:
 ```bash
 # Assuming the current directory corresponds to the Rust repository
 $ git checkout beta
+# Make sure to change `your-github-name` to your github name in the following command
 $ git subtree pull -p src/tools/clippy https://github.com/<your-github-name>/rust-clippy backport
 $ ./x.py test src/tools/clippy
 ```

Diff for: src/tools/clippy/book/src/development/infrastructure/sync.md

@@ -79,8 +79,7 @@ to be run inside the `rust` directory):
    `rustup check`.
 3. Sync the changes to the rust-copy of Clippy to your Clippy fork:
     ```bash
-    # Make sure to change `your-github-name` to your github name in the following command. Also be
-    # sure to either use a net-new branch, e.g. `sync-from-rust`, or delete the branch beforehand
+    # Be sure to either use a net-new branch, e.g. `sync-from-rust`, or delete the branch beforehand
     # because changes cannot be fast forwarded and you have to run this command again.
     git subtree push -P src/tools/clippy clippy-local sync-from-rust
     ```

Diff for: src/tools/clippy/book/src/lint_configuration.md

@@ -53,6 +53,7 @@ Please use that command to update the file and do not edit it by hand.
 | [ignore-interior-mutability](#ignore-interior-mutability) | `["bytes::Bytes"]` |
 | [allow-mixed-uninlined-format-args](#allow-mixed-uninlined-format-args) | `true` |
 | [suppress-restriction-lint-in-const](#suppress-restriction-lint-in-const) | `false` |
+| [missing-docs-in-crate-items](#missing-docs-in-crate-items) | `false` |
 
 ### arithmetic-side-effects-allowed
 Suppress checking of the passed type names in all types of operations.
@@ -471,31 +472,31 @@ The maximum size of a file included via `include_bytes!()` or `include_str!()`,
 
 
 ### allow-expect-in-tests
-Whether `expect` should be allowed within `#[cfg(test)]`
+Whether `expect` should be allowed in test functions or `#[cfg(test)]`
 
 **Default Value:** `false` (`bool`)
 
 * [expect_used](https://rust-lang.github.io/rust-clippy/master/index.html#expect_used)
 
 
 ### allow-unwrap-in-tests
-Whether `unwrap` should be allowed in test cfg
+Whether `unwrap` should be allowed in test functions or `#[cfg(test)]`
 
 **Default Value:** `false` (`bool`)
 
 * [unwrap_used](https://rust-lang.github.io/rust-clippy/master/index.html#unwrap_used)
 
 
 ### allow-dbg-in-tests
-Whether `dbg!` should be allowed in test functions
+Whether `dbg!` should be allowed in test functions or `#[cfg(test)]`
 
 **Default Value:** `false` (`bool`)
 
 * [dbg_macro](https://rust-lang.github.io/rust-clippy/master/index.html#dbg_macro)
 
 
 ### allow-print-in-tests
-Whether print macros (ex. `println!`) should be allowed in test functions
+Whether print macros (ex. `println!`) should be allowed in test functions or `#[cfg(test)]`
 
 **Default Value:** `false` (`bool`)
 
@@ -540,4 +541,13 @@ if no suggestion can be made.
 * [indexing_slicing](https://rust-lang.github.io/rust-clippy/master/index.html#indexing_slicing)
 
 
+### missing-docs-in-crate-items
+Whether to **only** check for missing documentation in items visible within the current
+crate. For example, `pub(crate)` items.
+
+**Default Value:** `false` (`bool`)
+
+* [missing_docs_in_private_items](https://rust-lang.github.io/rust-clippy/master/index.html#missing_docs_in_private_items)
+
+
 

Diff for: src/tools/clippy/clippy_dev/src/new_lint.rs

@@ -1,5 +1,6 @@
 use crate::clippy_project_root;
 use indoc::{formatdoc, writedoc};
+use std::fmt;
 use std::fmt::Write as _;
 use std::fs::{self, OpenOptions};
 use std::io::prelude::*;
@@ -256,7 +257,7 @@ fn get_lint_file_contents(lint: &LintData<'_>, enable_msrv: bool) -> String {
         )
     });
 
-    let _ = write!(result, "{}", get_lint_declaration(&name_upper, category));
+    let _: fmt::Result = write!(result, "{}", get_lint_declaration(&name_upper, category));
 
     result.push_str(&if enable_msrv {
         formatdoc!(
@@ -353,7 +354,7 @@ fn create_lint_for_ty(lint: &LintData<'_>, enable_msrv: bool, ty: &str) -> io::R
     let mut lint_file_contents = String::new();
 
     if enable_msrv {
-        let _ = writedoc!(
+        let _: fmt::Result = writedoc!(
             lint_file_contents,
             r#"
                 use clippy_utils::msrvs::{{self, Msrv}};
@@ -373,7 +374,7 @@ fn create_lint_for_ty(lint: &LintData<'_>, enable_msrv: bool, ty: &str) -> io::R
             name_upper = name_upper,
         );
     } else {
-        let _ = writedoc!(
+        let _: fmt::Result = writedoc!(
             lint_file_contents,
             r#"
                 use rustc_lint::{{{context_import}, LintContext}};
@@ -521,7 +522,7 @@ fn setup_mod_file(path: &Path, lint: &LintData<'_>) -> io::Result<&'static str>
         .chain(std::iter::once(&*lint_name_upper))
         .filter(|s| !s.is_empty())
     {
-        let _ = write!(new_arr_content, "\n    {ident},");
+        let _: fmt::Result = write!(new_arr_content, "\n    {ident},");
     }
     new_arr_content.push('\n');
 

Diff for: src/tools/clippy/clippy_dev/src/update_lints.rs

@@ -5,7 +5,7 @@ use itertools::Itertools;
 use rustc_lexer::{tokenize, unescape, LiteralKind, TokenKind};
 use std::collections::{HashMap, HashSet};
 use std::ffi::OsStr;
-use std::fmt::Write;
+use std::fmt::{self, Write};
 use std::fs::{self, OpenOptions};
 use std::io::{self, Read, Seek, SeekFrom, Write as _};
 use std::ops::Range;
@@ -691,7 +691,7 @@ fn gen_deprecated(lints: &[DeprecatedLint]) -> String {
     let mut output = GENERATED_FILE_COMMENT.to_string();
     output.push_str("{\n");
     for lint in lints {
-        let _ = write!(
+        let _: fmt::Result = write!(
             output,
             concat!(
                 "    store.register_removed(\n",
@@ -726,7 +726,7 @@ fn gen_declared_lints<'a>(
         if !is_public {
             output.push_str("    #[cfg(feature = \"internal\")]\n");
         }
-        let _ = writeln!(output, "    crate::{module_name}::{lint_name}_INFO,");
+        let _: fmt::Result = writeln!(output, "    crate::{module_name}::{lint_name}_INFO,");
     }
     output.push_str("];\n");
 

Diff for: src/tools/clippy/clippy_lints/src/box_default.rs

@@ -117,7 +117,8 @@ fn given_type(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
         ) => {
             if let Some(index) = args.iter().position(|arg| arg.hir_id == expr.hir_id) &&
                 let Some(sig) = expr_sig(cx, path) &&
-                let Some(input) = sig.input(index)
+                let Some(input) = sig.input(index) &&
+                !cx.typeck_results().expr_ty_adjusted(expr).boxed_ty().is_trait()
             {
                 input.no_bound_vars().is_some()
             } else {

Diff for: src/tools/clippy/clippy_lints/src/casts/cast_possible_truncation.rs

@@ -168,7 +168,7 @@ pub(super) fn check(
     let suggestion = format!("{cast_to_snip}::try_from({name_of_cast_from})");
 
     span_lint_and_then(cx, CAST_POSSIBLE_TRUNCATION, expr.span, &msg, |diag| {
-        diag.help("if this is intentional allow the lint with `#[allow(clippy::cast_precision_loss)]` ...");
+        diag.help("if this is intentional allow the lint with `#[allow(clippy::cast_possible_truncation)]` ...");
         diag.span_suggestion_with_style(
             expr.span,
             "... or use `try_from` and handle the error accordingly",

Diff for: src/tools/clippy/clippy_lints/src/declared_lints.rs

@@ -179,6 +179,7 @@ pub(crate) static LINTS: &[&crate::LintInfo] = &[
     crate::from_raw_with_void_ptr::FROM_RAW_WITH_VOID_PTR_INFO,
     crate::from_str_radix_10::FROM_STR_RADIX_10_INFO,
     crate::functions::DOUBLE_MUST_USE_INFO,
+    crate::functions::IMPL_TRAIT_IN_PARAMS_INFO,
     crate::functions::MISNAMED_GETTERS_INFO,
     crate::functions::MUST_USE_CANDIDATE_INFO,
     crate::functions::MUST_USE_UNIT_INFO,
@@ -224,6 +225,7 @@ pub(crate) static LINTS: &[&crate::LintInfo] = &[
     crate::let_underscore::LET_UNDERSCORE_FUTURE_INFO,
     crate::let_underscore::LET_UNDERSCORE_LOCK_INFO,
     crate::let_underscore::LET_UNDERSCORE_MUST_USE_INFO,
+    crate::let_underscore::LET_UNDERSCORE_UNTYPED_INFO,
     crate::lifetimes::EXTRA_UNUSED_LIFETIMES_INFO,
     crate::lifetimes::NEEDLESS_LIFETIMES_INFO,
     crate::literal_representation::DECIMAL_LITERAL_REPRESENTATION_INFO,
@@ -378,6 +380,7 @@ pub(crate) static LINTS: &[&crate::LintInfo] = &[
     crate::methods::SKIP_WHILE_NEXT_INFO,
     crate::methods::STABLE_SORT_PRIMITIVE_INFO,
     crate::methods::STRING_EXTEND_CHARS_INFO,
+    crate::methods::SUSPICIOUS_COMMAND_ARG_SPACE_INFO,
     crate::methods::SUSPICIOUS_MAP_INFO,
     crate::methods::SUSPICIOUS_SPLITN_INFO,
     crate::methods::SUSPICIOUS_TO_OWNED_INFO,
@@ -447,6 +450,7 @@ pub(crate) static LINTS: &[&crate::LintInfo] = &[
     crate::no_effect::NO_EFFECT_INFO,
     crate::no_effect::NO_EFFECT_UNDERSCORE_BINDING_INFO,
     crate::no_effect::UNNECESSARY_OPERATION_INFO,
+    crate::no_mangle_with_rust_abi::NO_MANGLE_WITH_RUST_ABI_INFO,
     crate::non_copy_const::BORROW_INTERIOR_MUTABLE_CONST_INFO,
     crate::non_copy_const::DECLARE_INTERIOR_MUTABLE_CONST_INFO,
     crate::non_expressive_names::JUST_UNDERSCORES_AND_DIGITS_INFO,
@@ -506,6 +510,7 @@ pub(crate) static LINTS: &[&crate::LintInfo] = &[
     crate::ptr_offset_with_cast::PTR_OFFSET_WITH_CAST_INFO,
     crate::pub_use::PUB_USE_INFO,
     crate::question_mark::QUESTION_MARK_INFO,
+    crate::question_mark_used::QUESTION_MARK_USED_INFO,
     crate::ranges::MANUAL_RANGE_CONTAINS_INFO,
     crate::ranges::RANGE_MINUS_ONE_INFO,
     crate::ranges::RANGE_PLUS_ONE_INFO,
@@ -536,6 +541,7 @@ pub(crate) static LINTS: &[&crate::LintInfo] = &[
     crate::shadow::SHADOW_REUSE_INFO,
     crate::shadow::SHADOW_SAME_INFO,
     crate::shadow::SHADOW_UNRELATED_INFO,
+    crate::significant_drop_tightening::SIGNIFICANT_DROP_TIGHTENING_INFO,
     crate::single_char_lifetime_names::SINGLE_CHAR_LIFETIME_NAMES_INFO,
     crate::single_component_path_imports::SINGLE_COMPONENT_PATH_IMPORTS_INFO,
     crate::size_of_in_element_count::SIZE_OF_IN_ELEMENT_COUNT_INFO,
@@ -573,6 +579,7 @@ pub(crate) static LINTS: &[&crate::LintInfo] = &[
     crate::transmute::TRANSMUTE_INT_TO_BOOL_INFO,
     crate::transmute::TRANSMUTE_INT_TO_CHAR_INFO,
     crate::transmute::TRANSMUTE_INT_TO_FLOAT_INFO,
+    crate::transmute::TRANSMUTE_INT_TO_NON_ZERO_INFO,
     crate::transmute::TRANSMUTE_NULL_TO_FN_INFO,
     crate::transmute::TRANSMUTE_NUM_TO_BYTES_INFO,
     crate::transmute::TRANSMUTE_PTR_TO_PTR_INFO,