Merge commit '2b030eb03d9e5837440b1ee0b98c50b97c0c5889' into clippyup

Author: flip1995

src/tools/clippy/CHANGELOG.md

@@ -5463,6 +5463,7 @@ Released 2018-09-13
 [`string_to_string`]: https://rust-lang.github.io/rust-clippy/master/index.html#string_to_string
 [`strlen_on_c_strings`]: https://rust-lang.github.io/rust-clippy/master/index.html#strlen_on_c_strings
 [`struct_excessive_bools`]: https://rust-lang.github.io/rust-clippy/master/index.html#struct_excessive_bools
+[`struct_field_names`]: https://rust-lang.github.io/rust-clippy/master/index.html#struct_field_names
 [`stutter`]: https://rust-lang.github.io/rust-clippy/master/index.html#stutter
 [`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
@@ -5625,6 +5626,7 @@ Released 2018-09-13
 [`single-char-binding-names-threshold`]: https://doc.rust-lang.org/clippy/lint_configuration.html#single-char-binding-names-threshold
 [`too-large-for-stack`]: https://doc.rust-lang.org/clippy/lint_configuration.html#too-large-for-stack
 [`enum-variant-name-threshold`]: https://doc.rust-lang.org/clippy/lint_configuration.html#enum-variant-name-threshold
+[`struct-field-name-threshold`]: https://doc.rust-lang.org/clippy/lint_configuration.html#struct-field-name-threshold
 [`enum-variant-size-threshold`]: https://doc.rust-lang.org/clippy/lint_configuration.html#enum-variant-size-threshold
 [`verbose-bit-mask-threshold`]: https://doc.rust-lang.org/clippy/lint_configuration.html#verbose-bit-mask-threshold
 [`literal-representation-threshold`]: https://doc.rust-lang.org/clippy/lint_configuration.html#literal-representation-threshold

src/tools/clippy/Cargo.toml

@@ -29,7 +29,7 @@ color-print = "0.3.4" # Sync version with Cargo
 anstream = "0.5.0"
 
 [dev-dependencies]
-ui_test = "0.20"
+ui_test = "0.21.2"
 tester = "0.9"
 regex = "1.5"
 toml = "0.7.3"

src/tools/clippy/book/src/development/adding_lints.md

@@ -30,6 +30,7 @@ because that's clearly a non-descriptive name.
   - [Documentation](#documentation)
   - [Running rustfmt](#running-rustfmt)
   - [Debugging](#debugging)
+  - [Conflicting lints](#conflicting-lints)
   - [PR Checklist](#pr-checklist)
   - [Adding configuration to a lint](#adding-configuration-to-a-lint)
   - [Cheat Sheet](#cheat-sheet)
@@ -612,6 +613,24 @@ output in the `stdout` part.
 
 [`dbg!`]: https://doc.rust-lang.org/std/macro.dbg.html
 
+## Conflicting lints
+
+There are several lints that deal with the same pattern but suggest different approaches. In other words, some lints
+may suggest modifications that go in the opposite direction to what some other lints already propose for the same
+code, creating conflicting diagnostics.
+
+When you are creating a lint that ends up in this scenario, the following tips should be encouraged to guide
+classification:
+
+* The only case where they should be in the same category is if that category is `restriction`. For example,
+`semicolon_inside_block` and `semicolon_outside_block`.
+* For all the other cases, they should be in different categories with different levels of allowance. For example,
+`implicit_return` (restriction, allow) and `needless_return` (style, warn).
+
+For lints that are in different categories, it is also recommended that at least one of them should be in the
+`restriction` category. The reason for this is that the `restriction` group is the only group where we don't
+recommend to enable the entire set, but cherry pick lints out of.
+
 ## PR Checklist
 
 Before submitting your PR make sure you followed all the basic requirements:

src/tools/clippy/book/src/lint_configuration.md

@@ -100,7 +100,7 @@ Suppress lints whenever the suggested change would cause breakage for other crat
 ## `msrv`
 The minimum rust version that the project supports
 
-**Default Value:** `None` (`Option<String>`)
+**Default Value:** `Msrv { stack: [] }` (`crate::Msrv`)
 
 ---
 **Affected lints:**
@@ -273,6 +273,16 @@ The minimum number of enum variants for the lints about variant names to trigger
 * [`enum_variant_names`](https://rust-lang.github.io/rust-clippy/master/index.html#enum_variant_names)
 
 
+## `struct-field-name-threshold`
+The minimum number of struct fields for the lints about field names to trigger
+
+**Default Value:** `3` (`u64`)
+
+---
+**Affected lints:**
+* [`struct_variant_names`](https://rust-lang.github.io/rust-clippy/master/index.html#struct_variant_names)
+
+
 ## `enum-variant-size-threshold`
 The maximum size of an enum's variant to avoid box suggestion
 

src/tools/clippy/clippy_lints/src/async_yields_async.rs

@@ -2,7 +2,7 @@ use clippy_utils::diagnostics::span_lint_hir_and_then;
 use clippy_utils::source::snippet;
 use clippy_utils::ty::implements_trait;
 use rustc_errors::Applicability;
-use rustc_hir::{AsyncCoroutineKind, Body, BodyId, ExprKind, CoroutineKind, QPath};
+use rustc_hir::{AsyncCoroutineKind, Body, BodyId, CoroutineKind, ExprKind, QPath};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 

src/tools/clippy/clippy_lints/src/await_holding_invalid.rs

@@ -287,5 +287,8 @@ fn is_mutex_guard(cx: &LateContext<'_>, def_id: DefId) -> bool {
 }
 
 fn is_refcell_ref(cx: &LateContext<'_>, def_id: DefId) -> bool {
-    matches!(cx.tcx.get_diagnostic_name(def_id), Some(sym::RefCellRef | sym::RefCellRefMut))
+    matches!(
+        cx.tcx.get_diagnostic_name(def_id),
+        Some(sym::RefCellRef | sym::RefCellRefMut)
+    )
 }

src/tools/clippy/clippy_lints/src/box_default.rs

@@ -3,8 +3,9 @@ use clippy_utils::macros::macro_backtrace;
 use clippy_utils::ty::expr_sig;
 use clippy_utils::{get_parent_node, is_default_equivalent, path_def_id};
 use rustc_errors::Applicability;
+use rustc_hir::def::Res;
 use rustc_hir::intravisit::{walk_ty, Visitor};
-use rustc_hir::{def::Res, Block, Expr, ExprKind, Local, Node, QPath, TyKind};
+use rustc_hir::{Block, Expr, ExprKind, Local, Node, QPath, TyKind};
 use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_middle::lint::in_external_macro;
 use rustc_middle::ty::print::with_forced_trimmed_paths;

src/tools/clippy/clippy_lints/src/declared_lints.rs

@@ -154,9 +154,6 @@ pub(crate) static LINTS: &[&crate::LintInfo] = &[
     crate::endian_bytes::LITTLE_ENDIAN_BYTES_INFO,
     crate::entry::MAP_ENTRY_INFO,
     crate::enum_clike::ENUM_CLIKE_UNPORTABLE_VARIANT_INFO,
-    crate::enum_variants::ENUM_VARIANT_NAMES_INFO,
-    crate::enum_variants::MODULE_INCEPTION_INFO,
-    crate::enum_variants::MODULE_NAME_REPETITIONS_INFO,
     crate::equatable_if_let::EQUATABLE_IF_LET_INFO,
     crate::error_impl_error::ERROR_IMPL_ERROR_INFO,
     crate::escape::BOXED_LOCAL_INFO,
@@ -226,6 +223,10 @@ pub(crate) static LINTS: &[&crate::LintInfo] = &[
     crate::instant_subtraction::UNCHECKED_DURATION_SUBTRACTION_INFO,
     crate::int_plus_one::INT_PLUS_ONE_INFO,
     crate::invalid_upcast_comparisons::INVALID_UPCAST_COMPARISONS_INFO,
+    crate::item_name_repetitions::ENUM_VARIANT_NAMES_INFO,
+    crate::item_name_repetitions::MODULE_INCEPTION_INFO,
+    crate::item_name_repetitions::MODULE_NAME_REPETITIONS_INFO,
+    crate::item_name_repetitions::STRUCT_FIELD_NAMES_INFO,
     crate::items_after_statements::ITEMS_AFTER_STATEMENTS_INFO,
     crate::items_after_test_module::ITEMS_AFTER_TEST_MODULE_INFO,
     crate::iter_not_returning_iterator::ITER_NOT_RETURNING_ITERATOR_INFO,

src/tools/clippy/clippy_lints/src/default_instead_of_iter_empty.rs

@@ -1,6 +1,6 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::source::snippet_with_context;
 use clippy_utils::last_path_segment;
+use clippy_utils::source::snippet_with_context;
 use rustc_errors::Applicability;
 use rustc_hir::{def, Expr, ExprKind, GenericArg, QPath, TyKind};
 use rustc_lint::{LateContext, LateLintPass};

src/tools/clippy/clippy_lints/src/exit.rs

@@ -1,5 +1,5 @@
 use clippy_utils::diagnostics::span_lint;
-use clippy_utils::{is_entrypoint_fn};
+use clippy_utils::is_entrypoint_fn;
 use if_chain::if_chain;
 use rustc_hir::{Expr, ExprKind, Item, ItemKind, Node};
 use rustc_lint::{LateContext, LateLintPass};