new lint: source_item_ordering

Author: decryphe

CHANGELOG.md

@@ -5331,6 +5331,7 @@ 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
@@ -6208,19 +6209,22 @@ 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
 [`semicolon-inside-block-ignore-singleline`]: https://doc.rust-lang.org/clippy/lint_configuration.html#semicolon-inside-block-ignore-singleline
 [`semicolon-outside-block-ignore-multiline`]: https://doc.rust-lang.org/clippy/lint_configuration.html#semicolon-outside-block-ignore-multiline
 [`single-char-binding-names-threshold`]: https://doc.rust-lang.org/clippy/lint_configuration.html#single-char-binding-names-threshold
+[`source-item-ordering`]: https://doc.rust-lang.org/clippy/lint_configuration.html#source-item-ordering
 [`stack-size-threshold`]: https://doc.rust-lang.org/clippy/lint_configuration.html#stack-size-threshold
 [`standard-macro-braces`]: https://doc.rust-lang.org/clippy/lint_configuration.html#standard-macro-braces
 [`struct-field-name-threshold`]: https://doc.rust-lang.org/clippy/lint_configuration.html#struct-field-name-threshold
 [`suppress-restriction-lint-in-const`]: https://doc.rust-lang.org/clippy/lint_configuration.html#suppress-restriction-lint-in-const
 [`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

@@ -666,6 +666,16 @@ 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", ["extern_crate", "mod", "foreign_mod"]], ["use", ["use"]], ["macros", ["macro"]], ["global_asm", ["global_asm"]], ["UPPER_SNAKE_CASE", ["static", "const"]], ["PascalCase", ["ty_alias", "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`
 
@@ -784,6 +794,16 @@ The maximum number of single char bindings a scope may have
 * [`many_single_char_names`](https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names)
 
 
+## `source-item-ordering`
+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)
+
+
 ## `stack-size-threshold`
 The maximum allowed stack size for functions in bytes
 
@@ -863,6 +883,16 @@ 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, SourceItemOrdering,
+    SourceItemOrderingCategory, SourceItemOrderingModuleItemGroupings, SourceItemOrderingModuleItemKind,
+    SourceItemOrderingTraitAssocItemKind, SourceItemOrderingTraitAssocItemKinds,
+};
 use rustc_errors::Applicability;
 use rustc_session::Session;
 use rustc_span::edit_distance::edit_distance;
@@ -47,6 +51,29 @@ 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", &[ExternCrate, Mod, ForeignMod]),
+        ("use", &[Use]),
+        ("macros", &[Macro]),
+        ("global_asm", &[GlobalAsm]),
+        ("UPPER_SNAKE_CASE", &[Static, Const]),
+        ("PascalCase", &[TyAlias, 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_SOURCE_ITEM_ORDERING: &[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)]
@@ -533,6 +560,9 @@ 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(
@@ -612,6 +642,9 @@ define_Conf! {
     /// The maximum number of single char bindings a scope may have
     #[lints(many_single_char_names)]
     single_char_binding_names_threshold: u64 = 4,
+    /// Which kind of elements should be ordered internally, possible values being `enum`, `impl`, `module`, `struct`, `trait`.
+    #[lints(arbitrary_source_item_ordering)]
+    source_item_ordering: SourceItemOrdering = DEFAULT_SOURCE_ITEM_ORDERING.into(),
     /// The maximum allowed stack size for functions in bytes
     #[lints(large_stack_frames)]
     stack_size_threshold: u64 = 512_000,
@@ -641,6 +674,9 @@ 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"]