new lint: source_item_ordering

Author: decryphe

CHANGELOG.md

@@ -5296,6 +5296,7 @@ Released 2018-09-13
 [`almost_complete_range`]: https://rust-lang.github.io/rust-clippy/master/index.html#almost_complete_range
 [`almost_swapped`]: https://rust-lang.github.io/rust-clippy/master/index.html#almost_swapped
 [`approx_constant`]: https://rust-lang.github.io/rust-clippy/master/index.html#approx_constant
+[`arbitrary_source_item_ordering`]: https://rust-lang.github.io/rust-clippy/master/index.html#arbitrary_source_item_ordering
 [`arc_with_non_send_sync`]: https://rust-lang.github.io/rust-clippy/master/index.html#arc_with_non_send_sync
 [`arithmetic_side_effects`]: https://rust-lang.github.io/rust-clippy/master/index.html#arithmetic_side_effects
 [`as_conversions`]: https://rust-lang.github.io/rust-clippy/master/index.html#as_conversions
@@ -6152,6 +6153,7 @@ Released 2018-09-13
 [`disallowed-types`]: https://doc.rust-lang.org/clippy/lint_configuration.html#disallowed-types
 [`doc-valid-idents`]: https://doc.rust-lang.org/clippy/lint_configuration.html#doc-valid-idents
 [`enable-raw-pointer-heuristic-for-send`]: https://doc.rust-lang.org/clippy/lint_configuration.html#enable-raw-pointer-heuristic-for-send
+[`enable-source-item-ordering-for`]: https://doc.rust-lang.org/clippy/lint_configuration.html#enable-source-item-ordering-for
 [`enforce-iter-loop-reborrow`]: https://doc.rust-lang.org/clippy/lint_configuration.html#enforce-iter-loop-reborrow
 [`enforced-import-renames`]: https://doc.rust-lang.org/clippy/lint_configuration.html#enforced-import-renames
 [`enum-variant-name-threshold`]: https://doc.rust-lang.org/clippy/lint_configuration.html#enum-variant-name-threshold
@@ -6169,6 +6171,7 @@ Released 2018-09-13
 [`max-trait-bounds`]: https://doc.rust-lang.org/clippy/lint_configuration.html#max-trait-bounds
 [`min-ident-chars-threshold`]: https://doc.rust-lang.org/clippy/lint_configuration.html#min-ident-chars-threshold
 [`missing-docs-in-crate-items`]: https://doc.rust-lang.org/clippy/lint_configuration.html#missing-docs-in-crate-items
+[`module-item-order-groupings`]: https://doc.rust-lang.org/clippy/lint_configuration.html#module-item-order-groupings
 [`msrv`]: https://doc.rust-lang.org/clippy/lint_configuration.html#msrv
 [`pass-by-value-size-limit`]: https://doc.rust-lang.org/clippy/lint_configuration.html#pass-by-value-size-limit
 [`pub-underscore-fields-behavior`]: https://doc.rust-lang.org/clippy/lint_configuration.html#pub-underscore-fields-behavior
@@ -6182,6 +6185,7 @@ Released 2018-09-13
 [`too-large-for-stack`]: https://doc.rust-lang.org/clippy/lint_configuration.html#too-large-for-stack
 [`too-many-arguments-threshold`]: https://doc.rust-lang.org/clippy/lint_configuration.html#too-many-arguments-threshold
 [`too-many-lines-threshold`]: https://doc.rust-lang.org/clippy/lint_configuration.html#too-many-lines-threshold
+[`trait-assoc-item-kinds-order`]: https://doc.rust-lang.org/clippy/lint_configuration.html#trait-assoc-item-kinds-order
 [`trivial-copy-size-limit`]: https://doc.rust-lang.org/clippy/lint_configuration.html#trivial-copy-size-limit
 [`type-complexity-threshold`]: https://doc.rust-lang.org/clippy/lint_configuration.html#type-complexity-threshold
 [`unnecessary-box-size`]: https://doc.rust-lang.org/clippy/lint_configuration.html#unnecessary-box-size

book/src/lint_configuration.md

@@ -473,6 +473,16 @@ Whether to apply the raw pointer heuristic to determine if a type is `Send`.
 * [`non_send_fields_in_send_ty`](https://rust-lang.github.io/rust-clippy/master/index.html#non_send_fields_in_send_ty)
 
 
+## `enable-source-item-ordering-for`
+Which kind of elements should be ordered internally, possible values being `enum`, `impl`, `module`, `struct`, `trait`.
+
+**Default Value:** `["enum", "impl", "module", "struct", "trait"]`
+
+---
+**Affected lints:**
+* [`arbitrary_source_item_ordering`](https://rust-lang.github.io/rust-clippy/master/index.html#arbitrary_source_item_ordering)
+
+
 ## `enforce-iter-loop-reborrow`
 Whether to recommend using implicit into iter for reborrowed values.
 
@@ -666,6 +676,16 @@ crate. For example, `pub(crate)` items.
 * [`missing_docs_in_private_items`](https://rust-lang.github.io/rust-clippy/master/index.html#missing_docs_in_private_items)
 
 
+## `module-item-order-groupings`
+The named groupings of different source item kinds within modules.
+
+**Default Value:** `[["modules", ["mod", "foreign_mod"]], ["use", ["use"]], ["macros", ["macro"]], ["global_asm", ["global_asm"]], ["UPPER_SNAKE_CASE", ["static", "const"]], ["PascalCase", ["ty_alias", "opaque_ty", "enum", "struct", "union", "trait", "trait_alias", "impl"]], ["lower_snake_case", ["fn"]]]`
+
+---
+**Affected lints:**
+* [`arbitrary_source_item_ordering`](https://rust-lang.github.io/rust-clippy/master/index.html#arbitrary_source_item_ordering)
+
+
 ## `msrv`
 The minimum rust version that the project supports. Defaults to the `rust-version` field in `Cargo.toml`
 
@@ -862,6 +882,16 @@ The maximum number of lines a function or method can have
 * [`too_many_lines`](https://rust-lang.github.io/rust-clippy/master/index.html#too_many_lines)
 
 
+## `trait-assoc-item-kinds-order`
+The order of associated items in traits.
+
+**Default Value:** `["const", "type", "fn"]`
+
+---
+**Affected lints:**
+* [`arbitrary_source_item_ordering`](https://rust-lang.github.io/rust-clippy/master/index.html#arbitrary_source_item_ordering)
+
+
 ## `trivial-copy-size-limit`
 The maximum size (in bytes) to consider a `Copy` type for passing by value instead of by
 reference. By default there is no limit

clippy_config/src/conf.rs

@@ -1,6 +1,10 @@
 use crate::ClippyConfiguration;
 use crate::msrvs::Msrv;
-use crate::types::{DisallowedPath, MacroMatcher, MatchLintBehaviour, PubUnderscoreFieldsBehaviour, Rename};
+use crate::types::{
+    DisallowedPath, MacroMatcher, MatchLintBehaviour, PubUnderscoreFieldsBehaviour, Rename, SourceItemOrderingCategory,
+    SourceItemOrderingEnableFor, SourceItemOrderingModuleItemGroupings, SourceItemOrderingModuleItemKind,
+    SourceItemOrderingTraitAssocItemKind, SourceItemOrderingTraitAssocItemKinds,
+};
 use rustc_errors::Applicability;
 use rustc_session::Session;
 use rustc_span::edit_distance::edit_distance;
@@ -46,6 +50,32 @@ const DEFAULT_ALLOWED_IDENTS_BELOW_MIN_CHARS: &[&str] = &["i", "j", "x", "y", "z
 const DEFAULT_ALLOWED_PREFIXES: &[&str] = &["to", "as", "into", "from", "try_into", "try_from"];
 const DEFAULT_ALLOWED_TRAITS_WITH_RENAMED_PARAMS: &[&str] =
     &["core::convert::From", "core::convert::TryFrom", "core::str::FromStr"];
+const DEFAULT_MODULE_ITEM_ORDERING_GROUPS: &[(&str, &[SourceItemOrderingModuleItemKind])] = {
+    #[allow(clippy::enum_glob_use)] // Very local glob use for legibility.
+    use SourceItemOrderingModuleItemKind::*;
+    &[
+        ("modules", &[Mod, ForeignMod]),
+        ("use", &[Use]),
+        ("macros", &[Macro]),
+        ("global_asm", &[GlobalAsm]),
+        ("UPPER_SNAKE_CASE", &[Static, Const]),
+        (
+            "PascalCase",
+            &[TyAlias, OpaqueTy, Enum, Struct, Union, Trait, TraitAlias, Impl],
+        ),
+        ("lower_snake_case", &[Fn]),
+    ]
+};
+const DEFAULT_TRAIT_ASSOC_ITEM_KINDS_ORDER: &[SourceItemOrderingTraitAssocItemKind] = {
+    #[allow(clippy::enum_glob_use)] // Very local glob use for legibility.
+    use SourceItemOrderingTraitAssocItemKind::*;
+    &[Const, Type, Fn]
+};
+const DEFAULT_ENABLE_SOURCE_ITEM_ORDERING_FOR: &[SourceItemOrderingCategory] = {
+    #[allow(clippy::enum_glob_use)] // Very local glob use for legibility.
+    use SourceItemOrderingCategory::*;
+    &[Enum, Impl, Module, Struct, Trait]
+};
 
 /// Conf with parse errors
 #[derive(Default)]
@@ -459,6 +489,9 @@ define_Conf! {
     /// Whether to apply the raw pointer heuristic to determine if a type is `Send`.
     #[lints(non_send_fields_in_send_ty)]
     enable_raw_pointer_heuristic_for_send: bool = true,
+    /// Which kind of elements should be ordered internally, possible values being `enum`, `impl`, `module`, `struct`, `trait`.
+    #[lints(arbitrary_source_item_ordering)]
+    enable_source_item_ordering_for: SourceItemOrderingEnableFor = DEFAULT_ENABLE_SOURCE_ITEM_ORDERING_FOR.into(),
     /// Whether to recommend using implicit into iter for reborrowed values.
     ///
     /// #### Example
@@ -530,6 +563,9 @@ define_Conf! {
     /// crate. For example, `pub(crate)` items.
     #[lints(missing_docs_in_private_items)]
     missing_docs_in_crate_items: bool = false,
+    /// The named groupings of different source item kinds within modules.
+    #[lints(arbitrary_source_item_ordering)]
+    module_item_order_groupings: SourceItemOrderingModuleItemGroupings = DEFAULT_MODULE_ITEM_ORDERING_GROUPS.into(),
     /// The minimum rust version that the project supports. Defaults to the `rust-version` field in `Cargo.toml`
     #[default_text = "current version"]
     #[lints(
@@ -637,6 +673,9 @@ define_Conf! {
     /// The maximum number of lines a function or method can have
     #[lints(too_many_lines)]
     too_many_lines_threshold: u64 = 100,
+    /// The order of associated items in traits.
+    #[lints(arbitrary_source_item_ordering)]
+    trait_assoc_item_kinds_order: SourceItemOrderingTraitAssocItemKinds = DEFAULT_TRAIT_ASSOC_ITEM_KINDS_ORDER.into(),
     /// The maximum size (in bytes) to consider a `Copy` type for passing by value instead of by
     /// reference. By default there is no limit
     #[default_text = "target_pointer_width * 2"]